Changeset - aaeaf5986496
[Not reviewed]
0 11 3
MH - 4 years ago 2021-03-24 20:07:06
contact@maxhenger.nl
some refactoring of comma-separated lexing, basic initial lexing tests, WIP on struct literals
13 files changed with 881 insertions and 365 deletions:
0 comments (0 inline, 0 general)
src/protocol/ast.rs
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// TODO: @cleanup, rigorous cleanup of dead code and silly object-oriented
 
//  trait impls where I deem them unfit.
 

	
 
use std::fmt;
 
use std::fmt::{Debug, Display, Formatter};
 
use std::ops::{Index, IndexMut};
 

	
 
use super::arena::{Arena, Id};
 
// use super::containers::StringAllocator;
 

	
 
// TODO: @cleanup, transform wrapping types into type aliases where possible
 
use crate::protocol::inputsource::*;
 

	
 
/// Helper macro that defines a type alias for a AST element ID. In this case 
 
/// only used to alias the `Id<T>` types.
 
macro_rules! define_aliased_ast_id {
 
    // Variant where we just defined the alias, without any indexing
 
    ($name:ident, $parent:ty) => {
 
        pub type $name = $parent;
 
    };
 
    // Variant where we define the type, and the Index and IndexMut traits
 
    ($name:ident, $parent:ty, $indexed_type:ty, $indexed_arena:ident) => {
 
        define_aliased_ast_id!($name, $parent);
 
        impl Index<$name> for Heap {
 
            type Output = $indexed_type;
 
            fn index(&self, index: $name) -> &Self::Output {
 
                &self.$indexed_arena[index]
 
            }
 
        }
 

	
 
        impl IndexMut<$name> for Heap {
 
            fn index_mut(&mut self, index: $name) -> &mut Self::Output {
 
                &mut self.$indexed_arena[index]
 
            }
 
        }
 
    }
 
}
 

	
 
/// Helper macro that defines a wrapper type for a particular variant of an AST
 
/// element ID. Only used to define single-wrapping IDs.
 
macro_rules! define_new_ast_id {
 
    // Variant where we just defined the new type, without any indexing
 
    ($name:ident, $parent:ty) => {
 
        #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, serde::Serialize, serde::Deserialize)]
 
        pub struct $name (pub(crate) $parent);
 

	
 
        impl $name {
 
            pub fn upcast(self) -> $parent {
 
                self.0
 
            }
 
        }
 
    };
 
    // Variant where we define the type, and the Index and IndexMut traits
 
    ($name:ident, $parent:ty, $indexed_type:ty, $wrapper_type:path, $indexed_arena:ident) => {
 
        define_new_ast_id!($name, $parent);
 
        impl Index<$name> for Heap {
 
            type Output = $indexed_type;
 
            fn index(&self, index: $name) -> &Self::Output {
 
                if let $wrapper_type(v) = &self.$indexed_arena[index.0] {
 
                    v
 
                } else {
 
                    unreachable!()
 
                }
 
            }
 
        }
 

	
 
        impl IndexMut<$name> for Heap {
 
            fn index_mut(&mut self, index: $name) -> &mut Self::Output {
 
                if let $wrapper_type(v) = &mut self.$indexed_arena[index.0] {
 
                    v
 
                } else {
 
                    unreachable!()
 
                }
 
            }
 
        }
 
    }
 
}
 

	
 
define_aliased_ast_id!(RootId, Id<Root>, Root, protocol_descriptions);
 
define_aliased_ast_id!(PragmaId, Id<Pragma>, Pragma, pragmas);
 
define_aliased_ast_id!(ImportId, Id<Import>, Import, imports);
 
define_aliased_ast_id!(ParserTypeId, Id<ParserType>, ParserType, parser_types);
 

	
 
define_aliased_ast_id!(VariableId, Id<Variable>, Variable, variables);
 
define_new_ast_id!(ParameterId, VariableId, Parameter, Variable::Parameter, variables);
 
define_new_ast_id!(LocalId, VariableId, Local, Variable::Local, variables);
 

	
 
define_aliased_ast_id!(DefinitionId, Id<Definition>, Definition, definitions);
 
define_new_ast_id!(StructId, DefinitionId, StructDefinition, Definition::Struct, definitions);
 
define_new_ast_id!(EnumId, DefinitionId, EnumDefinition, Definition::Enum, definitions);
 
define_new_ast_id!(ComponentId, DefinitionId, Component, Definition::Component, definitions);
 
define_new_ast_id!(FunctionId, DefinitionId, Function, Definition::Function, definitions);
 

	
 
define_aliased_ast_id!(StatementId, Id<Statement>, Statement, statements);
 
define_new_ast_id!(BlockStatementId, StatementId, BlockStatement, Statement::Block, statements);
 
define_new_ast_id!(LocalStatementId, StatementId, LocalStatement, Statement::Local, statements);
 
define_new_ast_id!(MemoryStatementId, LocalStatementId);
 
define_new_ast_id!(ChannelStatementId, LocalStatementId);
 
define_new_ast_id!(SkipStatementId, StatementId, SkipStatement, Statement::Skip, statements);
 
define_new_ast_id!(LabeledStatementId, StatementId, LabeledStatement, Statement::Labeled, statements);
 
define_new_ast_id!(IfStatementId, StatementId, IfStatement, Statement::If, statements);
 
define_new_ast_id!(EndIfStatementId, StatementId, EndIfStatement, Statement::EndIf, statements);
 
define_new_ast_id!(WhileStatementId, StatementId, WhileStatement, Statement::While, statements);
 
define_new_ast_id!(EndWhileStatementId, StatementId, EndWhileStatement, Statement::EndWhile, statements);
 
define_new_ast_id!(BreakStatementId, StatementId, BreakStatement, Statement::Break, statements);
 
define_new_ast_id!(ContinueStatementId, StatementId, ContinueStatement, Statement::Continue, statements);
 
define_new_ast_id!(SynchronousStatementId, StatementId, SynchronousStatement, Statement::Synchronous, statements);
 
define_new_ast_id!(EndSynchronousStatementId, StatementId, EndSynchronousStatement, Statement::EndSynchronous, statements);
 
define_new_ast_id!(ReturnStatementId, StatementId, ReturnStatement, Statement::Return, statements);
 
define_new_ast_id!(AssertStatementId, StatementId, AssertStatement, Statement::Assert, statements);
 
define_new_ast_id!(GotoStatementId, StatementId, GotoStatement, Statement::Goto, statements);
 
define_new_ast_id!(NewStatementId, StatementId, NewStatement, Statement::New, statements);
 
define_new_ast_id!(ExpressionStatementId, StatementId, ExpressionStatement, Statement::Expression, statements);
 

	
 
define_aliased_ast_id!(ExpressionId, Id<Expression>, Expression, expressions);
 
define_new_ast_id!(AssignmentExpressionId, ExpressionId, AssignmentExpression, Expression::Assignment, expressions);
 
define_new_ast_id!(ConditionalExpressionId, ExpressionId, ConditionalExpression, Expression::Conditional, expressions);
 
define_new_ast_id!(BinaryExpressionId, ExpressionId, BinaryExpression, Expression::Binary, expressions);
 
define_new_ast_id!(UnaryExpressionId, ExpressionId, UnaryExpression, Expression::Unary, expressions);
 
define_new_ast_id!(IndexingExpressionId, ExpressionId, IndexingExpression, Expression::Indexing, expressions);
 
define_new_ast_id!(SlicingExpressionId, ExpressionId, SlicingExpression, Expression::Slicing, expressions);
 
define_new_ast_id!(SelectExpressionId, ExpressionId, SelectExpression, Expression::Select, expressions);
 
define_new_ast_id!(ArrayExpressionId, ExpressionId, ArrayExpression, Expression::Array, expressions);
 
define_new_ast_id!(ConstantExpressionId, ExpressionId, ConstantExpression, Expression::Constant, expressions);
 
define_new_ast_id!(LiteralExpressionId, ExpressionId, LiteralExpression, Expression::Literal, expressions);
 
define_new_ast_id!(CallExpressionId, ExpressionId, CallExpression, Expression::Call, expressions);
 
define_new_ast_id!(VariableExpressionId, ExpressionId, VariableExpression, Expression::Variable, expressions);
 

	
 
// TODO: @cleanup - pub qualifiers can be removed once done
 
#[derive(Debug, serde::Serialize, serde::Deserialize)]
 
pub struct Heap {
 
    // Root arena, contains the entry point for different modules. Each root
 
    // contains lists of IDs that correspond to the other arenas.
 
    pub(crate) protocol_descriptions: Arena<Root>,
 
    // Contents of a file, these are the elements the `Root` elements refer to
 
    pragmas: Arena<Pragma>,
 
    pub(crate) imports: Arena<Import>,
 
    identifiers: Arena<Identifier>,
 
    pub(crate) parser_types: Arena<ParserType>,
 
    pub(crate) variables: Arena<Variable>,
 
    pub(crate) definitions: Arena<Definition>,
 
    pub(crate) statements: Arena<Statement>,
 
    pub(crate) expressions: Arena<Expression>,
 
}
 

	
 
impl Heap {
 
    pub fn new() -> Heap {
 
        Heap {
 
            // string_alloc: StringAllocator::new(),
 
            protocol_descriptions: Arena::new(),
 
            pragmas: Arena::new(),
 
            imports: Arena::new(),
 
            identifiers: Arena::new(),
 
            parser_types: Arena::new(),
 
            variables: Arena::new(),
 
            definitions: Arena::new(),
 
            statements: Arena::new(),
 
            expressions: Arena::new(),
 
        }
 
    }
 
    pub fn alloc_parser_type(
 
        &mut self,
 
        f: impl FnOnce(ParserTypeId) -> ParserType,
 
    ) -> ParserTypeId {
 
        self.parser_types.alloc_with_id(|id| f(id))
 
    }
 

	
 
    pub fn alloc_parameter(&mut self, f: impl FnOnce(ParameterId) -> Parameter) -> ParameterId {
 
        ParameterId(
 
            self.variables.alloc_with_id(|id| Variable::Parameter(f(ParameterId(id)))),
 
        )
 
    }
 
    pub fn alloc_local(&mut self, f: impl FnOnce(LocalId) -> Local) -> LocalId {
 
        LocalId(
 
            self.variables.alloc_with_id(|id| Variable::Local(f(LocalId(id)))),
 
        )
 
    }
 
    pub fn alloc_assignment_expression(
 
        &mut self,
 
        f: impl FnOnce(AssignmentExpressionId) -> AssignmentExpression,
 
    ) -> AssignmentExpressionId {
 
        AssignmentExpressionId(
 
            self.expressions.alloc_with_id(|id| {
 
                Expression::Assignment(f(AssignmentExpressionId(id)))
 
            })
 
        )
 
    }
 
    pub fn alloc_conditional_expression(
 
        &mut self,
 
        f: impl FnOnce(ConditionalExpressionId) -> ConditionalExpression,
 
    ) -> ConditionalExpressionId {
 
        ConditionalExpressionId(
 
            self.expressions.alloc_with_id(|id| {
 
                Expression::Conditional(f(ConditionalExpressionId(id)))
 
            })
 
        )
 
    }
 
    pub fn alloc_binary_expression(
 
        &mut self,
 
        f: impl FnOnce(BinaryExpressionId) -> BinaryExpression,
 
    ) -> BinaryExpressionId {
 
        BinaryExpressionId(
 
            self.expressions
 
                .alloc_with_id(|id| Expression::Binary(f(BinaryExpressionId(id)))),
 
        )
 
    }
 
    pub fn alloc_unary_expression(
 
        &mut self,
 
        f: impl FnOnce(UnaryExpressionId) -> UnaryExpression,
 
    ) -> UnaryExpressionId {
 
        UnaryExpressionId(
 
            self.expressions
 
                .alloc_with_id(|id| Expression::Unary(f(UnaryExpressionId(id)))),
 
        )
 
    }
 
    pub fn alloc_slicing_expression(
 
        &mut self,
 
        f: impl FnOnce(SlicingExpressionId) -> SlicingExpression,
 
    ) -> SlicingExpressionId {
 
        SlicingExpressionId(
 
            self.expressions
 
                .alloc_with_id(|id| Expression::Slicing(f(SlicingExpressionId(id)))),
 
        )
 
    }
 
    pub fn alloc_indexing_expression(
 
        &mut self,
 
        f: impl FnOnce(IndexingExpressionId) -> IndexingExpression,
 
    ) -> IndexingExpressionId {
 
        IndexingExpressionId(
 
            self.expressions.alloc_with_id(|id| {
 
                Expression::Indexing(f(IndexingExpressionId(id)))
 
            }),
 
        )
 
    }
 
    pub fn alloc_select_expression(
 
        &mut self,
 
        f: impl FnOnce(SelectExpressionId) -> SelectExpression,
 
    ) -> SelectExpressionId {
 
        SelectExpressionId(
 
            self.expressions
 
                .alloc_with_id(|id| Expression::Select(f(SelectExpressionId(id)))),
 
        )
 
    }
 
    pub fn alloc_array_expression(
 
        &mut self,
 
        f: impl FnOnce(ArrayExpressionId) -> ArrayExpression,
 
    ) -> ArrayExpressionId {
 
        ArrayExpressionId(
 
            self.expressions
 
                .alloc_with_id(|id| Expression::Array(f(ArrayExpressionId(id)))),
 
        )
 
    }
 
    pub fn alloc_constant_expression(
 
    pub fn alloc_literal_expression(
 
        &mut self,
 
        f: impl FnOnce(ConstantExpressionId) -> ConstantExpression,
 
    ) -> ConstantExpressionId {
 
        ConstantExpressionId(
 
        f: impl FnOnce(LiteralExpressionId) -> LiteralExpression,
 
    ) -> LiteralExpressionId {
 
        LiteralExpressionId(
 
            self.expressions.alloc_with_id(|id| {
 
                Expression::Constant(f(ConstantExpressionId(id)))
 
                Expression::Literal(f(LiteralExpressionId(id)))
 
            }),
 
        )
 
    }
 
    pub fn alloc_call_expression(
 
        &mut self,
 
        f: impl FnOnce(CallExpressionId) -> CallExpression,
 
    ) -> CallExpressionId {
 
        CallExpressionId(
 
            self.expressions
 
                .alloc_with_id(|id| Expression::Call(f(CallExpressionId(id)))),
 
        )
 
    }
 
    pub fn alloc_variable_expression(
 
        &mut self,
 
        f: impl FnOnce(VariableExpressionId) -> VariableExpression,
 
    ) -> VariableExpressionId {
 
        VariableExpressionId(
 
            self.expressions.alloc_with_id(|id| {
 
                Expression::Variable(f(VariableExpressionId(id)))
 
            }),
 
        )
 
    }
 
    pub fn alloc_block_statement(
 
        &mut self,
 
        f: impl FnOnce(BlockStatementId) -> BlockStatement,
 
    ) -> BlockStatementId {
 
        BlockStatementId(
 
            self.statements
 
                .alloc_with_id(|id| Statement::Block(f(BlockStatementId(id)))),
 
        )
 
    }
 
    pub fn alloc_memory_statement(
 
        &mut self,
 
        f: impl FnOnce(MemoryStatementId) -> MemoryStatement,
 
    ) -> MemoryStatementId {
 
        MemoryStatementId(LocalStatementId(self.statements.alloc_with_id(|id| {
 
            Statement::Local(LocalStatement::Memory(
 
                f(MemoryStatementId(LocalStatementId(id)))
 
            ))
 
        })))
 
    }
 
    pub fn alloc_channel_statement(
 
        &mut self,
 
        f: impl FnOnce(ChannelStatementId) -> ChannelStatement,
 
    ) -> ChannelStatementId {
 
        ChannelStatementId(LocalStatementId(self.statements.alloc_with_id(|id| {
 
            Statement::Local(LocalStatement::Channel(
 
                f(ChannelStatementId(LocalStatementId(id)))
 
            ))
 
        })))
 
    }
 
    pub fn alloc_skip_statement(
 
        &mut self,
 
        f: impl FnOnce(SkipStatementId) -> SkipStatement,
 
    ) -> SkipStatementId {
 
        SkipStatementId(
 
            self.statements
 
                .alloc_with_id(|id| Statement::Skip(f(SkipStatementId(id)))),
 
        )
 
    }
 
    pub fn alloc_if_statement(
 
        &mut self,
 
        f: impl FnOnce(IfStatementId) -> IfStatement,
 
    ) -> IfStatementId {
 
        IfStatementId(
 
            self.statements.alloc_with_id(|id| Statement::If(f(IfStatementId(id)))),
 
        )
 
    }
 
    pub fn alloc_end_if_statement(
 
        &mut self,
 
        f: impl FnOnce(EndIfStatementId) -> EndIfStatement,
 
    ) -> EndIfStatementId {
 
        EndIfStatementId(
 
            self.statements
 
                .alloc_with_id(|id| Statement::EndIf(f(EndIfStatementId(id)))),
 
        )
 
    }
 
    pub fn alloc_while_statement(
 
        &mut self,
 
        f: impl FnOnce(WhileStatementId) -> WhileStatement,
 
    ) -> WhileStatementId {
 
        WhileStatementId(
 
            self.statements
 
                .alloc_with_id(|id| Statement::While(f(WhileStatementId(id)))),
 
        )
 
    }
 
    pub fn alloc_end_while_statement(
 
        &mut self,
 
        f: impl FnOnce(EndWhileStatementId) -> EndWhileStatement,
 
    ) -> EndWhileStatementId {
 
        EndWhileStatementId(
 
            self.statements
 
                .alloc_with_id(|id| Statement::EndWhile(f(EndWhileStatementId(id)))),
 
        )
 
    }
 
    pub fn alloc_break_statement(
 
        &mut self,
 
        f: impl FnOnce(BreakStatementId) -> BreakStatement,
 
    ) -> BreakStatementId {
 
        BreakStatementId(
 
            self.statements
 
                .alloc_with_id(|id| Statement::Break(f(BreakStatementId(id)))),
 
        )
 
    }
 
    pub fn alloc_continue_statement(
 
        &mut self,
 
        f: impl FnOnce(ContinueStatementId) -> ContinueStatement,
 
    ) -> ContinueStatementId {
 
        ContinueStatementId(
 
            self.statements
 
                .alloc_with_id(|id| Statement::Continue(f(ContinueStatementId(id)))),
 
        )
 
    }
 
    pub fn alloc_synchronous_statement(
 
        &mut self,
 
        f: impl FnOnce(SynchronousStatementId) -> SynchronousStatement,
 
    ) -> SynchronousStatementId {
 
        SynchronousStatementId(self.statements.alloc_with_id(|id| {
 
            Statement::Synchronous(f(SynchronousStatementId(id)))
 
        }))
 
    }
 
    pub fn alloc_end_synchronous_statement(
 
        &mut self,
 
        f: impl FnOnce(EndSynchronousStatementId) -> EndSynchronousStatement,
 
    ) -> EndSynchronousStatementId {
 
        EndSynchronousStatementId(self.statements.alloc_with_id(|id| {
 
            Statement::EndSynchronous(f(EndSynchronousStatementId(id)))
 
        }))
 
    }
 
    pub fn alloc_return_statement(
 
        &mut self,
 
        f: impl FnOnce(ReturnStatementId) -> ReturnStatement,
 
    ) -> ReturnStatementId {
 
        ReturnStatementId(
 
            self.statements
 
                .alloc_with_id(|id| Statement::Return(f(ReturnStatementId(id)))),
 
        )
 
    }
 
    pub fn alloc_assert_statement(
 
        &mut self,
 
        f: impl FnOnce(AssertStatementId) -> AssertStatement,
 
    ) -> AssertStatementId {
 
        AssertStatementId(
 
            self.statements
 
                .alloc_with_id(|id| Statement::Assert(f(AssertStatementId(id)))),
 
        )
 
    }
 
    pub fn alloc_goto_statement(
 
        &mut self,
 
        f: impl FnOnce(GotoStatementId) -> GotoStatement,
 
    ) -> GotoStatementId {
 
        GotoStatementId(
 
            self.statements
 
                .alloc_with_id(|id| Statement::Goto(f(GotoStatementId(id)))),
 
        )
 
    }
 
    pub fn alloc_new_statement(
 
        &mut self,
 
        f: impl FnOnce(NewStatementId) -> NewStatement,
 
    ) -> NewStatementId {
 
        NewStatementId(
 
            self.statements.alloc_with_id(|id| Statement::New(f(NewStatementId(id)))),
 
        )
 
    }
 
    pub fn alloc_labeled_statement(
 
        &mut self,
 
        f: impl FnOnce(LabeledStatementId) -> LabeledStatement,
 
    ) -> LabeledStatementId {
 
        LabeledStatementId(
 
            self.statements
 
                .alloc_with_id(|id| Statement::Labeled(f(LabeledStatementId(id)))),
 
        )
 
    }
 
    pub fn alloc_expression_statement(
 
        &mut self,
 
        f: impl FnOnce(ExpressionStatementId) -> ExpressionStatement,
 
    ) -> ExpressionStatementId {
 
        ExpressionStatementId(
 
            self.statements.alloc_with_id(|id| {
 
                Statement::Expression(f(ExpressionStatementId(id)))
 
            }),
 
        )
 
    }
 
    pub fn alloc_struct_definition(&mut self, f: impl FnOnce(StructId) -> StructDefinition) -> StructId {
 
        StructId(self.definitions.alloc_with_id(|id| {
 
            Definition::Struct(f(StructId(id)))
 
        }))
 
    }
 
    pub fn alloc_enum_definition(&mut self, f: impl FnOnce(EnumId) -> EnumDefinition) -> EnumId {
 
        EnumId(self.definitions.alloc_with_id(|id| {
 
            Definition::Enum(f(EnumId(id)))
 
        }))
 
    }
 
    pub fn alloc_component(&mut self, f: impl FnOnce(ComponentId) -> Component) -> ComponentId {
 
        ComponentId(self.definitions.alloc_with_id(|id| {
 
            Definition::Component(f(ComponentId(id)))
 
        }))
 
    }
 
    pub fn alloc_function(&mut self, f: impl FnOnce(FunctionId) -> Function) -> FunctionId {
 
        FunctionId(
 
            self.definitions
 
                .alloc_with_id(|id| Definition::Function(f(FunctionId(id)))),
 
        )
 
    }
 
    pub fn alloc_pragma(&mut self, f: impl FnOnce(PragmaId) -> Pragma) -> PragmaId {
 
        self.pragmas.alloc_with_id(|id| f(id))
 
    }
 
    pub fn alloc_import(&mut self, f: impl FnOnce(ImportId) -> Import) -> ImportId {
 
        self.imports.alloc_with_id(|id| f(id))
 
    }
 
    pub fn alloc_protocol_description(&mut self, f: impl FnOnce(RootId) -> Root) -> RootId {
 
        self.protocol_descriptions.alloc_with_id(|id| f(id))
 
    }
 
}
 

	
 
impl Index<MemoryStatementId> for Heap {
 
    type Output = MemoryStatement;
 
    fn index(&self, index: MemoryStatementId) -> &Self::Output {
 
        &self.statements[index.0.0].as_memory()
 
    }
 
}
 

	
 
impl Index<ChannelStatementId> for Heap {
 
    type Output = ChannelStatement;
 
    fn index(&self, index: ChannelStatementId) -> &Self::Output {
 
        &self.statements[index.0.0].as_channel()
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct Root {
 
    pub this: RootId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub pragmas: Vec<PragmaId>,
 
    pub imports: Vec<ImportId>,
 
    pub definitions: Vec<DefinitionId>,
 
}
 

	
 
impl Root {
 
    pub fn get_definition_ident(&self, h: &Heap, id: &[u8]) -> Option<DefinitionId> {
 
        for &def in self.definitions.iter() {
 
            if h[def].identifier().value == id {
 
                return Some(def);
 
            }
 
        }
 
        None
 
    }
 
}
 

	
 
impl SyntaxElement for Root {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum Pragma {
 
    Version(PragmaVersion),
 
    Module(PragmaModule)
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct PragmaVersion {
 
    pub this: PragmaId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub version: u64,
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct PragmaModule {
 
    pub this: PragmaId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub value: Vec<u8>,
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct PragmaOld {
 
    pub this: PragmaId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub value: Vec<u8>,
 
}
 

	
 
impl SyntaxElement for PragmaOld {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum Import {
 
    Module(ImportModule),
 
    Symbols(ImportSymbols)
 
}
 

	
 
impl Import {
 
    pub(crate) fn as_module(&self) -> &ImportModule {
 
        match self {
 
            Import::Module(m) => m,
 
            _ => panic!("Unable to cast 'Import' to 'ImportModule'")
 
        }
 
    }
 
    pub(crate) fn as_symbols(&self) -> &ImportSymbols {
 
        match self {
 
            Import::Symbols(m) => m,
 
            _ => panic!("Unable to cast 'Import' to 'ImportSymbols'")
 
        }
 
    }
 
}
 

	
 
impl SyntaxElement for Import {
 
    fn position(&self) -> InputPosition {
 
        match self {
 
            Import::Module(m) => m.position,
 
            Import::Symbols(m) => m.position
 
        }
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct ImportModule {
 
    pub this: ImportId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub module_name: Vec<u8>,
 
    pub alias: Vec<u8>,
 
    // Phase 2: module resolving
 
    pub module_id: Option<RootId>,
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct AliasedSymbol {
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub name: Vec<u8>,
 
    pub alias: Vec<u8>,
 
    // Phase 2: symbol resolving
 
    pub definition_id: Option<DefinitionId>,
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct ImportSymbols {
 
    pub this: ImportId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub module_name: Vec<u8>,
 
    // Phase 2: module resolving
 
    pub module_id: Option<RootId>,
 
    // Phase 1&2
 
    // if symbols is empty, then we implicitly import all symbols without any
 
    // aliases for them. If it is not empty, then symbols are explicitly
 
    // specified, and optionally given an alias.
 
    pub symbols: Vec<AliasedSymbol>,
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct Identifier {
 
    pub position: InputPosition,
 
    pub value: Vec<u8>
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct NamespacedIdentifier {
 
    pub position: InputPosition,
 
    pub num_namespaces: u8,
 
    pub value: Vec<u8>,
 
}
 

	
 
impl NamespacedIdentifier {
 
    pub(crate) fn iter(&self) -> NamespacedIdentifierIter {
 
        NamespacedIdentifierIter{
 
            value: &self.value,
 
            cur_offset: 0,
 
            num_returned: 0,
 
            num_total: self.num_namespaces
 
        }
 
    }
 
}
 

	
 
impl PartialEq for NamespacedIdentifier {
 
    fn eq(&self, other: &Self) -> bool {
 
        return self.value == other.value
 
    }
 
}
 
impl Eq for NamespacedIdentifier{}
 

	
 
// TODO: Just keep ref to NamespacedIdentifier
 
pub(crate) struct NamespacedIdentifierIter<'a> {
 
    value: &'a Vec<u8>,
 
    cur_offset: usize,
 
    num_returned: u8,
 
    num_total: u8,
 
}
 

	
 
impl<'a> NamespacedIdentifierIter<'a> {
 
    pub(crate) fn num_returned(&self) -> u8 {
 
        return self.num_returned;
 
    }
 
    pub(crate) fn num_remaining(&self) -> u8 {
 
        return self.num_total - self.num_returned
 
    }
 
    pub(crate) fn returned_section(&self) -> &[u8] {
 
        // Offset always includes the two trailing ':' characters
 
        let end = if self.cur_offset >= 2 { self.cur_offset - 2 } else { self.cur_offset };
 
        return &self.value[..end]
 
    }
 
}
 

	
 
impl<'a> Iterator for NamespacedIdentifierIter<'a> {
 
    type Item = &'a [u8];
 
    fn next(&mut self) -> Option<Self::Item> {
 
        if self.cur_offset >= self.value.len() {
 
            debug_assert_eq!(self.num_returned, self.num_total);
 
            None
 
        } else {
 
            debug_assert!(self.num_returned < self.num_total);
 
            let start = self.cur_offset;
 
            let mut end = start;
 
            while end < self.value.len() - 1 {
 
                if self.value[end] == b':' && self.value[end + 1] == b':' {
 
                    self.cur_offset = end + 2;
 
                    self.num_returned += 1;
 
                    return Some(&self.value[start..end]);
 
                }
 
                end += 1;
 
            }
 

	
 
            // If NamespacedIdentifier is constructed properly, then we cannot
 
            // end with "::" in the value, so
 
            debug_assert!(end == 0 || (self.value[end - 1] != b':' && self.value[end] != b':'));
 
            debug_assert_eq!(self.num_returned + 1, self.num_total);
 
            self.cur_offset = self.value.len();
 
            self.num_returned += 1;
 
            return Some(&self.value[start..]);
 
        }
 
    }
 
}
 

	
 
impl Display for Identifier {
 
    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
 
        // A source identifier is in ASCII range.
 
        write!(f, "{}", String::from_utf8_lossy(&self.value))
 
    }
 
}
 

	
 
/// TODO: @types Remove the Message -> Byte hack at some point...
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum ParserTypeVariant {
 
    // Basic builtin
 
    Message,
 
    Bool,
 
    Byte,
 
    Short,
 
    Int,
 
    Long,
 
    String,
 
    // Literals (need to get concrete builtin type during typechecking)
 
    IntegerLiteral,
 
    Inferred,
 
    // Complex builtins
 
    Array(ParserTypeId), // array of a type
 
    Input(ParserTypeId), // typed input endpoint of a channel
 
    Output(ParserTypeId), // typed output endpoint of a channel
 
    Symbolic(SymbolicParserType), // symbolic type (definition or polyarg)
 
}
 

	
 
impl ParserTypeVariant {
 
    pub(crate) fn supports_polymorphic_args(&self) -> bool {
 
        use ParserTypeVariant::*;
 
        match self {
 
            Message | Bool | Byte | Short | Int | Long | String | IntegerLiteral | Inferred => false,
 
            _ => true
 
        }
 
    }
 
}
 

	
 
/// ParserType is a specification of a type during the parsing phase and initial
 
/// linker/validator phase of the compilation process. These types may be
 
/// (partially) inferred or represent literals (e.g. a integer whose bytesize is
 
/// not yet determined).
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct ParserType {
 
    pub this: ParserTypeId,
 
    pub pos: InputPosition,
 
    pub variant: ParserTypeVariant,
 
}
 

	
 
/// SymbolicParserType is the specification of a symbolic type. During the
 
/// parsing phase we will only store the identifier of the type. During the
 
/// validation phase we will determine whether it refers to a user-defined type,
 
/// or a polymorphic argument. After the validation phase it may still be the
 
/// case that the resulting `variant` will not pass the typechecker.
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct SymbolicParserType {
 
    // Phase 1: parser
 
    pub identifier: NamespacedIdentifier,
 
    /// The user-specified polymorphic arguments. Zero-length implies that the
 
    /// user did not specify any of them, and they're either not needed or all
 
    /// need to be inferred. Otherwise the number of polymorphic arguments must
 
    /// match those of the corresponding definition
 
    pub poly_args: Vec<ParserTypeId>,
 
    // Phase 2: validation/linking (for types in function/component bodies) and
 
    //  type table construction (for embedded types of structs/unions)
 
    pub variant: Option<SymbolicParserTypeVariant>
 
}
 

	
 
/// Specifies whether the symbolic type points to an actual user-defined type,
 
/// or whether it points to a polymorphic argument within the definition (e.g.
 
/// a defined variable `T var` within a function `int func<T>()`
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum SymbolicParserTypeVariant {
 
    Definition(DefinitionId),
 
    // TODO: figure out if I need the DefinitionId here
 
    PolyArg(DefinitionId, usize), // index of polyarg in the definition
 
}
 

	
 
/// ConcreteType is the representation of a type after resolving symbolic types
 
/// and performing type inference
 
#[derive(Debug, Clone, Copy, Eq, PartialEq, serde::Serialize, serde::Deserialize)]
 
pub enum ConcreteTypePart {
 
    // Markers for the use of polymorphic types within a procedure's body that
 
    // refer to polymorphic variables on the procedure's definition. Different
 
    // from markers in the `InferenceType`, these will not contain nested types.
 
    Marker(usize),
 
    // Special types (cannot be explicitly constructed by the programmer)
 
    Void,
 
    // Builtin types without nested types
 
    Message,
 
    Bool,
 
    Byte,
 
    Short,
 
    Int,
 
    Long,
 
    String,
 
    // Builtin types with one nested type
 
    Array,
 
    Slice,
 
    Input,
 
    Output,
 
    // User defined type with any number of nested types
 
    Instance(DefinitionId, usize),
 
}
 

	
 
#[derive(Debug, Clone, Eq, PartialEq, serde::Serialize, serde::Deserialize)]
 
pub struct ConcreteType {
 
    pub(crate) parts: Vec<ConcreteTypePart>
 
}
 

	
 
impl Default for ConcreteType {
 
    fn default() -> Self {
 
        Self{ parts: Vec::new() }
 
    }
 
}
 

	
 
impl ConcreteType {
 
    pub(crate) fn has_marker(&self) -> bool {
 
        self.parts
 
            .iter()
 
            .any(|p| {
 
                if let ConcreteTypePart::Marker(_) = p { true } else { false }
 
            })
 
    }
 
}
 

	
 
// TODO: Remove at some point
 
#[derive(Debug, Clone, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
 
pub enum PrimitiveType {
 
    Unassigned,
 
    Input,
 
    Output,
 
    Message,
 
    Boolean,
 
    Byte,
 
    Short,
 
    Int,
 
    Long,
 
    Symbolic(PrimitiveSymbolic)
 
}
 

	
 
// TODO: @cleanup, remove PartialEq implementations
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct PrimitiveSymbolic {
 
    // Phase 1: parser
 
    pub(crate) identifier: NamespacedIdentifier,
 
    // Phase 2: typing
 
    pub(crate) definition: Option<DefinitionId>
 
}
 

	
 
impl PartialEq for PrimitiveSymbolic {
 
    fn eq(&self, other: &Self) -> bool {
 
        self.identifier == other.identifier
 
    }
 
}
 
impl Eq for PrimitiveSymbolic{}
 

	
 
#[derive(Debug, Clone, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
 
pub struct Type {
 
    pub primitive: PrimitiveType,
 
    pub array: bool,
 
}
 

	
 
#[allow(dead_code)]
 
impl Type {
 
    pub const UNASSIGNED: Type = Type { primitive: PrimitiveType::Unassigned, array: false };
 

	
 
    pub const INPUT: Type = Type { primitive: PrimitiveType::Input, array: false };
 
    pub const OUTPUT: Type = Type { primitive: PrimitiveType::Output, array: false };
 
    pub const MESSAGE: Type = Type { primitive: PrimitiveType::Message, array: false };
 
    pub const BOOLEAN: Type = Type { primitive: PrimitiveType::Boolean, array: false };
 
    pub const BYTE: Type = Type { primitive: PrimitiveType::Byte, array: false };
 
    pub const SHORT: Type = Type { primitive: PrimitiveType::Short, array: false };
 
    pub const INT: Type = Type { primitive: PrimitiveType::Int, array: false };
 
    pub const LONG: Type = Type { primitive: PrimitiveType::Long, array: false };
 

	
 
    pub const INPUT_ARRAY: Type = Type { primitive: PrimitiveType::Input, array: true };
 
    pub const OUTPUT_ARRAY: Type = Type { primitive: PrimitiveType::Output, array: true };
 
    pub const MESSAGE_ARRAY: Type = Type { primitive: PrimitiveType::Message, array: true };
 
    pub const BOOLEAN_ARRAY: Type = Type { primitive: PrimitiveType::Boolean, array: true };
 
    pub const BYTE_ARRAY: Type = Type { primitive: PrimitiveType::Byte, array: true };
 
    pub const SHORT_ARRAY: Type = Type { primitive: PrimitiveType::Short, array: true };
 
    pub const INT_ARRAY: Type = Type { primitive: PrimitiveType::Int, array: true };
 
    pub const LONG_ARRAY: Type = Type { primitive: PrimitiveType::Long, array: true };
 
}
 

	
 
impl Display for Type {
 
    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
 
        match &self.primitive {
 
            PrimitiveType::Unassigned => {
 
                write!(f, "unassigned")?;
 
            }
 
            PrimitiveType::Input => {
 
                write!(f, "in")?;
 
            }
 
            PrimitiveType::Output => {
 
                write!(f, "out")?;
 
            }
 
            PrimitiveType::Message => {
 
                write!(f, "msg")?;
 
            }
 
            PrimitiveType::Boolean => {
 
                write!(f, "boolean")?;
 
            }
 
            PrimitiveType::Byte => {
 
                write!(f, "byte")?;
 
            }
 
            PrimitiveType::Short => {
 
                write!(f, "short")?;
 
            }
 
            PrimitiveType::Int => {
 
                write!(f, "int")?;
 
            }
 
            PrimitiveType::Long => {
 
                write!(f, "long")?;
 
            }
 
            PrimitiveType::Symbolic(data) => {
 
                // Type data is in ASCII range.
 
                if let Some(id) = &data.definition {
 
                    write!(
 
                        f, "Symbolic({}, id: {})", 
 
                        String::from_utf8_lossy(&data.identifier.value),
 
                        id.index
 
                    )?;
 
                } else {
 
                    write!(
 
                        f, "Symbolic({}, id: Unresolved)",
 
                        String::from_utf8_lossy(&data.identifier.value)
 
                    )?;
 
                }
 
            }
 
        }
 
        if self.array {
 
            write!(f, "[]")
 
        } else {
 
            Ok(())
 
        }
 
    }
 
}
 

	
 
type CharacterData = Vec<u8>;
 
type IntegerData = i64;
 
type LiteralCharacter = Vec<u8>;
 
type LiteralInteger = i64; // TODO: @int_literal
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum Constant {
 
pub enum Literal {
 
    Null, // message
 
    True,
 
    False,
 
    Character(CharacterData),
 
    Integer(IntegerData),
 
    Character(LiteralCharacter),
 
    Integer(LiteralInteger),
 
    Struct(LiteralStruct),
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct LiteralStructField {
 
    // Phase 1: parser
 
    pub(crate) identifier: Identifier,
 
    pub(crate) value: ExpressionId,
 
    // Phase 2: linker
 
    pub(crate) field_idx: usize, // in struct definition
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct LiteralStruct {
 
    // Phase 1: parser
 
    pub(crate) identifier: NamespacedIdentifier,
 
    pub(crate) poly_args: Vec<ParserTypeId>,
 
    pub(crate) fields: Vec<LiteralStructField>,
 
    // Phase 2: linker
 
    pub(crate) definition: Option<DefinitionId>
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum Method {
 
    Get,
 
    Put,
 
    Fires,
 
    Create,
 
    Symbolic(MethodSymbolic)
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct MethodSymbolic {
 
    pub(crate) identifier: NamespacedIdentifier,
 
    pub(crate) definition: Option<DefinitionId>
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum Field {
 
    Length,
 
    Symbolic(Identifier),
 
}
 
impl Field {
 
    pub fn is_length(&self) -> bool {
 
        match self {
 
            Field::Length => true,
 
            _ => false,
 
        }
 
    }
 
}
 

	
 
#[derive(Debug, Clone, Copy, serde::Serialize, serde::Deserialize)]
 
pub enum Scope {
 
    Definition(DefinitionId),
 
    Regular(BlockStatementId),
 
    Synchronous((SynchronousStatementId, BlockStatementId)),
 
}
 

	
 
impl Scope {
 
    pub fn is_block(&self) -> bool {
 
        match &self {
 
            Scope::Definition(_) => false,
 
            Scope::Regular(_) => true,
 
            Scope::Synchronous(_) => true,
 
        }
 
    }
 
    pub fn to_block(&self) -> BlockStatementId {
 
        match &self {
 
            Scope::Regular(id) => *id,
 
            Scope::Synchronous((_, id)) => *id,
 
            _ => panic!("unable to get BlockStatement from Scope")
 
        }
 
    }
 
}
 

	
 
pub trait VariableScope {
 
    fn parent_scope(&self, h: &Heap) -> Option<Scope>;
 
    fn get_variable(&self, h: &Heap, id: &Identifier) -> Option<VariableId>;
 
}
 

	
 
impl VariableScope for Scope {
 
    fn parent_scope(&self, h: &Heap) -> Option<Scope> {
 
        match self {
 
            Scope::Definition(def) => h[*def].parent_scope(h),
 
            Scope::Regular(stmt) => h[*stmt].parent_scope(h),
 
            Scope::Synchronous((stmt, _)) => h[*stmt].parent_scope(h),
 
        }
 
    }
 
    fn get_variable(&self, h: &Heap, id: &Identifier) -> Option<VariableId> {
 
        match self {
 
            Scope::Definition(def) => h[*def].get_variable(h, id),
 
            Scope::Regular(stmt) => h[*stmt].get_variable(h, id),
 
            Scope::Synchronous((stmt, _)) => h[*stmt].get_variable(h, id),
 
        }
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum Variable {
 
    Parameter(Parameter),
 
    Local(Local),
 
}
 

	
 
impl Variable {
 
    pub fn identifier(&self) -> &Identifier {
 
        match self {
 
            Variable::Parameter(var) => &var.identifier,
 
            Variable::Local(var) => &var.identifier,
 
        }
 
    }
 
    pub fn is_parameter(&self) -> bool {
 
        match self {
 
            Variable::Parameter(_) => true,
 
            _ => false,
 
        }
 
    }
 
    pub fn as_parameter(&self) -> &Parameter {
 
        match self {
 
            Variable::Parameter(result) => result,
 
            _ => panic!("Unable to cast `Variable` to `Parameter`"),
 
        }
 
    }
 
    pub fn as_local(&self) -> &Local {
 
        match self {
 
            Variable::Local(result) => result,
 
            _ => panic!("Unable to cast `Variable` to `Local`"),
 
        }
 
    }
 
    pub fn as_local_mut(&mut self) -> &mut Local {
 
        match self {
 
            Variable::Local(result) => result,
 
            _ => panic!("Unable to cast 'Variable' to 'Local'"),
 
        }
 
    }
 
}
 

	
 
impl SyntaxElement for Variable {
 
    fn position(&self) -> InputPosition {
 
        match self {
 
            Variable::Parameter(decl) => decl.position(),
 
            Variable::Local(decl) => decl.position(),
 
        }
 
    }
 
}
 

	
 
/// TODO: Remove distinction between parameter/local and add an enum to indicate
 
///     the distinction between the two
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct Parameter {
 
    pub this: ParameterId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub parser_type: ParserTypeId,
 
    pub identifier: Identifier,
 
}
 

	
 
impl SyntaxElement for Parameter {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct Local {
 
    pub this: LocalId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub parser_type: ParserTypeId,
 
    pub identifier: Identifier,
 
    // Phase 2: linker
 
    pub relative_pos_in_block: u32,
 
}
 
impl SyntaxElement for Local {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum Definition {
 
    Struct(StructDefinition),
 
    Enum(EnumDefinition),
 
    Component(Component),
 
    Function(Function),
 
}
 

	
 
impl Definition {
 
    pub fn is_struct(&self) -> bool {
 
        match self {
 
            Definition::Struct(_) => true,
 
            _ => false
 
        }
 
    }
 
    pub fn as_struct(&self) -> &StructDefinition {
 
        match self {
 
            Definition::Struct(result) => result,
 
            _ => panic!("Unable to cast 'Definition' to 'StructDefinition'"),
 
        }
 
    }
 
    pub fn is_enum(&self) -> bool {
 
        match self {
 
            Definition::Enum(_) => true,
 
            _ => false,
 
        }
 
    }
 
    pub fn as_enum(&self) -> &EnumDefinition {
 
        match self {
 
            Definition::Enum(result) => result,
 
            _ => panic!("Unable to cast 'Definition' to 'EnumDefinition'"),
 
        }
 
    }
 
    pub fn is_component(&self) -> bool {
 
        match self {
 
            Definition::Component(_) => true,
 
            _ => false,
 
        }
 
    }
 
    pub fn as_component(&self) -> &Component {
 
        match self {
 
            Definition::Component(result) => result,
 
            _ => panic!("Unable to cast `Definition` to `Component`"),
 
        }
 
    }
 
    pub fn is_function(&self) -> bool {
 
        match self {
 
            Definition::Function(_) => true,
 
            _ => false,
 
        }
 
    }
 
    pub fn as_function(&self) -> &Function {
 
        match self {
 
            Definition::Function(result) => result,
 
            _ => panic!("Unable to cast `Definition` to `Function`"),
 
        }
 
    }
 
    pub fn identifier(&self) -> &Identifier {
 
        match self {
 
            Definition::Struct(def) => &def.identifier,
 
            Definition::Enum(def) => &def.identifier,
 
            Definition::Component(com) => &com.identifier,
 
            Definition::Function(fun) => &fun.identifier,
 
        }
 
    }
 
    pub fn parameters(&self) -> &Vec<ParameterId> {
 
        // TODO: Fix this
 
        static EMPTY_VEC: Vec<ParameterId> = Vec::new();
 
        match self {
 
            Definition::Component(com) => &com.parameters,
 
            Definition::Function(fun) => &fun.parameters,
 
            _ => &EMPTY_VEC,
 
        }
 
    }
 
    pub fn body(&self) -> StatementId {
 
        // TODO: Fix this
 
        match self {
 
            Definition::Component(com) => com.body,
 
            Definition::Function(fun) => fun.body,
 
            _ => panic!("cannot retrieve body (for EnumDefinition or StructDefinition)")
 
        }
 
    }
 
}
 

	
 
impl SyntaxElement for Definition {
 
    fn position(&self) -> InputPosition {
 
        match self {
 
            Definition::Struct(def) => def.position,
 
            Definition::Enum(def) => def.position,
 
            Definition::Component(def) => def.position(),
 
            Definition::Function(def) => def.position(),
 
        }
 
    }
 
}
 

	
 
impl VariableScope for Definition {
 
    fn parent_scope(&self, _h: &Heap) -> Option<Scope> {
 
        None
 
    }
 
    fn get_variable(&self, h: &Heap, id: &Identifier) -> Option<VariableId> {
 
        for &parameter_id in self.parameters().iter() {
 
            let parameter = &h[parameter_id];
 
            if parameter.identifier.value == id.value {
 
                return Some(parameter_id.0);
 
            }
 
        }
 
        None
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct StructFieldDefinition {
 
    pub position: InputPosition,
 
    pub field: Identifier,
 
    pub parser_type: ParserTypeId,
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct StructDefinition {
 
    pub this: StructId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub identifier: Identifier,
 
    pub poly_vars: Vec<Identifier>,
 
    pub fields: Vec<StructFieldDefinition>
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize, PartialEq)]
 
pub enum EnumVariantValue {
 
    None,
 
    Integer(i64),
 
    Type(ParserTypeId),
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct EnumVariantDefinition {
 
    pub position: InputPosition,
 
    pub identifier: Identifier,
 
    pub value: EnumVariantValue,
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct EnumDefinition {
 
    pub this: EnumId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub identifier: Identifier,
 
    pub poly_vars: Vec<Identifier>,
 
    pub variants: Vec<EnumVariantDefinition>,
 
}
 

	
 
#[derive(Debug, Clone, Copy, serde::Serialize, serde::Deserialize)]
 
pub enum ComponentVariant {
 
    Primitive,
 
    Composite,
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct Component {
 
    pub this: ComponentId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub variant: ComponentVariant,
 
    pub identifier: Identifier,
 
    pub poly_vars: Vec<Identifier>,
 
    pub parameters: Vec<ParameterId>,
 
    pub body: StatementId,
 
}
 

	
 
impl SyntaxElement for Component {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct Function {
 
    pub this: FunctionId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub return_type: ParserTypeId,
 
    pub identifier: Identifier,
 
    pub poly_vars: Vec<Identifier>,
 
    pub parameters: Vec<ParameterId>,
 
    pub body: StatementId,
 
}
 

	
 
impl SyntaxElement for Function {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum Statement {
 
    Block(BlockStatement),
 
    Local(LocalStatement),
 
    Skip(SkipStatement),
 
    Labeled(LabeledStatement),
 
    If(IfStatement),
 
    EndIf(EndIfStatement),
 
    While(WhileStatement),
 
    EndWhile(EndWhileStatement),
 
    Break(BreakStatement),
 
    Continue(ContinueStatement),
 
    Synchronous(SynchronousStatement),
 
    EndSynchronous(EndSynchronousStatement),
 
    Return(ReturnStatement),
 
    Assert(AssertStatement),
 
    Goto(GotoStatement),
 
    New(NewStatement),
 
    Expression(ExpressionStatement),
 
}
 

	
 
impl Statement {
 
    pub fn as_block(&self) -> &BlockStatement {
 
        match self {
 
            Statement::Block(result) => result,
 
            _ => panic!("Unable to cast `Statement` to `BlockStatement`"),
 
        }
 
    }
 
    pub fn as_block_mut(&mut self) -> &mut BlockStatement {
 
        match self {
 
            Statement::Block(result) => result,
 
            _ => panic!("Unable to cast `Statement` to `BlockStatement`"),
 
        }
 
@@ -1575,805 +1595,805 @@ impl BlockStatement {
 
}
 

	
 
impl SyntaxElement for BlockStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
impl VariableScope for BlockStatement {
 
    fn parent_scope(&self, _h: &Heap) -> Option<Scope> {
 
        self.parent_scope.clone()
 
    }
 
    fn get_variable(&self, h: &Heap, id: &Identifier) -> Option<VariableId> {
 
        for local_id in self.locals.iter() {
 
            let local = &h[*local_id];
 
            if local.identifier.value == id.value {
 
                return Some(local_id.0);
 
            }
 
        }
 
        None
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum LocalStatement {
 
    Memory(MemoryStatement),
 
    Channel(ChannelStatement),
 
}
 

	
 
impl LocalStatement {
 
    pub fn this(&self) -> LocalStatementId {
 
        match self {
 
            LocalStatement::Memory(stmt) => stmt.this.upcast(),
 
            LocalStatement::Channel(stmt) => stmt.this.upcast(),
 
        }
 
    }
 
    pub fn as_memory(&self) -> &MemoryStatement {
 
        match self {
 
            LocalStatement::Memory(result) => result,
 
            _ => panic!("Unable to cast `LocalStatement` to `MemoryStatement`"),
 
        }
 
    }
 
    pub fn as_channel(&self) -> &ChannelStatement {
 
        match self {
 
            LocalStatement::Channel(result) => result,
 
            _ => panic!("Unable to cast `LocalStatement` to `ChannelStatement`"),
 
        }
 
    }
 
    pub fn next(&self) -> Option<StatementId> {
 
        match self {
 
            LocalStatement::Memory(stmt) => stmt.next,
 
            LocalStatement::Channel(stmt) => stmt.next,
 
        }
 
    }
 
}
 

	
 
impl SyntaxElement for LocalStatement {
 
    fn position(&self) -> InputPosition {
 
        match self {
 
            LocalStatement::Memory(stmt) => stmt.position(),
 
            LocalStatement::Channel(stmt) => stmt.position(),
 
        }
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct MemoryStatement {
 
    pub this: MemoryStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub variable: LocalId,
 
    // Phase 2: linker
 
    pub next: Option<StatementId>,
 
}
 

	
 
impl SyntaxElement for MemoryStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
/// ChannelStatement is the declaration of an input and output port associated
 
/// with the same channel. Note that the polarity of the ports are from the
 
/// point of view of the component. So an output port is something that a
 
/// component uses to send data over (i.e. it is the "input end" of the
 
/// channel), and vice versa.
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct ChannelStatement {
 
    pub this: ChannelStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub from: LocalId, // output
 
    pub to: LocalId,   // input
 
    // Phase 2: linker
 
    pub relative_pos_in_block: u32,
 
    pub next: Option<StatementId>,
 
}
 

	
 
impl SyntaxElement for ChannelStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct SkipStatement {
 
    pub this: SkipStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    // Phase 2: linker
 
    pub next: Option<StatementId>,
 
}
 

	
 
impl SyntaxElement for SkipStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct LabeledStatement {
 
    pub this: LabeledStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub label: Identifier,
 
    pub body: StatementId,
 
    // Phase 2: linker
 
    pub relative_pos_in_block: u32,
 
    pub in_sync: Option<SynchronousStatementId>,
 
}
 

	
 
impl SyntaxElement for LabeledStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct IfStatement {
 
    pub this: IfStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub test: ExpressionId,
 
    pub true_body: StatementId,
 
    pub false_body: StatementId,
 
    // Phase 2: linker
 
    pub end_if: Option<EndIfStatementId>,
 
}
 

	
 
impl SyntaxElement for IfStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct EndIfStatement {
 
    pub this: EndIfStatementId,
 
    // Phase 2: linker
 
    pub start_if: IfStatementId,
 
    pub position: InputPosition, // of corresponding if statement
 
    pub next: Option<StatementId>,
 
}
 

	
 
impl SyntaxElement for EndIfStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct WhileStatement {
 
    pub this: WhileStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub test: ExpressionId,
 
    pub body: StatementId,
 
    // Phase 2: linker
 
    pub end_while: Option<EndWhileStatementId>,
 
    pub in_sync: Option<SynchronousStatementId>,
 
}
 

	
 
impl SyntaxElement for WhileStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct EndWhileStatement {
 
    pub this: EndWhileStatementId,
 
    // Phase 2: linker
 
    pub start_while: WhileStatementId,
 
    pub position: InputPosition, // of corresponding while
 
    pub next: Option<StatementId>,
 
}
 

	
 
impl SyntaxElement for EndWhileStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct BreakStatement {
 
    pub this: BreakStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub label: Option<Identifier>,
 
    // Phase 2: linker
 
    pub target: Option<EndWhileStatementId>,
 
}
 

	
 
impl SyntaxElement for BreakStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct ContinueStatement {
 
    pub this: ContinueStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub label: Option<Identifier>,
 
    // Phase 2: linker
 
    pub target: Option<WhileStatementId>,
 
}
 

	
 
impl SyntaxElement for ContinueStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct SynchronousStatement {
 
    pub this: SynchronousStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    // pub parameters: Vec<ParameterId>,
 
    pub body: StatementId,
 
    // Phase 2: linker
 
    pub end_sync: Option<EndSynchronousStatementId>,
 
    pub parent_scope: Option<Scope>,
 
}
 

	
 
impl SyntaxElement for SynchronousStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
impl VariableScope for SynchronousStatement {
 
    fn parent_scope(&self, _h: &Heap) -> Option<Scope> {
 
        self.parent_scope.clone()
 
    }
 
    fn get_variable(&self, _h: &Heap, _id: &Identifier) -> Option<VariableId> {
 
        // TODO: Another case of "where was this used for?"
 
        // for parameter_id in self.parameters.iter() {
 
        //     let parameter = &h[*parameter_id];
 
        //     if parameter.identifier.value == id.value {
 
        //         return Some(parameter_id.0);
 
        //     }
 
        // }
 
        None
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct EndSynchronousStatement {
 
    pub this: EndSynchronousStatementId,
 
    // Phase 2: linker
 
    pub position: InputPosition, // of corresponding sync statement
 
    pub start_sync: SynchronousStatementId,
 
    pub next: Option<StatementId>,
 
}
 

	
 
impl SyntaxElement for EndSynchronousStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct ReturnStatement {
 
    pub this: ReturnStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub expression: ExpressionId,
 
}
 

	
 
impl SyntaxElement for ReturnStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct AssertStatement {
 
    pub this: AssertStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub expression: ExpressionId,
 
    // Phase 2: linker
 
    pub next: Option<StatementId>,
 
}
 

	
 
impl SyntaxElement for AssertStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct GotoStatement {
 
    pub this: GotoStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub label: Identifier,
 
    // Phase 2: linker
 
    pub target: Option<LabeledStatementId>,
 
}
 

	
 
impl SyntaxElement for GotoStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct NewStatement {
 
    pub this: NewStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub expression: CallExpressionId,
 
    // Phase 2: linker
 
    pub next: Option<StatementId>,
 
}
 

	
 
impl SyntaxElement for NewStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct ExpressionStatement {
 
    pub this: ExpressionStatementId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub expression: ExpressionId,
 
    // Phase 2: linker
 
    pub next: Option<StatementId>,
 
}
 

	
 
impl SyntaxElement for ExpressionStatement {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, PartialEq, Eq, Clone, Copy, serde::Serialize, serde::Deserialize)]
 
pub enum ExpressionParent {
 
    None, // only set during initial parsing
 
    If(IfStatementId),
 
    While(WhileStatementId),
 
    Return(ReturnStatementId),
 
    Assert(AssertStatementId),
 
    New(NewStatementId),
 
    ExpressionStmt(ExpressionStatementId),
 
    Expression(ExpressionId, u32) // index within expression (e.g LHS or RHS of expression)
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum Expression {
 
    Assignment(AssignmentExpression),
 
    Conditional(ConditionalExpression),
 
    Binary(BinaryExpression),
 
    Unary(UnaryExpression),
 
    Indexing(IndexingExpression),
 
    Slicing(SlicingExpression),
 
    Select(SelectExpression),
 
    Array(ArrayExpression),
 
    Constant(ConstantExpression),
 
    Literal(LiteralExpression),
 
    Call(CallExpression),
 
    Variable(VariableExpression),
 
}
 

	
 
impl Expression {
 
    pub fn as_assignment(&self) -> &AssignmentExpression {
 
        match self {
 
            Expression::Assignment(result) => result,
 
            _ => panic!("Unable to cast `Expression` to `AssignmentExpression`"),
 
        }
 
    }
 
    pub fn as_conditional(&self) -> &ConditionalExpression {
 
        match self {
 
            Expression::Conditional(result) => result,
 
            _ => panic!("Unable to cast `Expression` to `ConditionalExpression`"),
 
        }
 
    }
 
    pub fn as_binary(&self) -> &BinaryExpression {
 
        match self {
 
            Expression::Binary(result) => result,
 
            _ => panic!("Unable to cast `Expression` to `BinaryExpression`"),
 
        }
 
    }
 
    pub fn as_unary(&self) -> &UnaryExpression {
 
        match self {
 
            Expression::Unary(result) => result,
 
            _ => panic!("Unable to cast `Expression` to `UnaryExpression`"),
 
        }
 
    }
 
    pub fn as_indexing(&self) -> &IndexingExpression {
 
        match self {
 
            Expression::Indexing(result) => result,
 
            _ => panic!("Unable to cast `Expression` to `IndexingExpression`"),
 
        }
 
    }
 
    pub fn as_slicing(&self) -> &SlicingExpression {
 
        match self {
 
            Expression::Slicing(result) => result,
 
            _ => panic!("Unable to cast `Expression` to `SlicingExpression`"),
 
        }
 
    }
 
    pub fn as_select(&self) -> &SelectExpression {
 
        match self {
 
            Expression::Select(result) => result,
 
            _ => panic!("Unable to cast `Expression` to `SelectExpression`"),
 
        }
 
    }
 
    pub fn as_array(&self) -> &ArrayExpression {
 
        match self {
 
            Expression::Array(result) => result,
 
            _ => panic!("Unable to cast `Expression` to `ArrayExpression`"),
 
        }
 
    }
 
    pub fn as_constant(&self) -> &ConstantExpression {
 
    pub fn as_constant(&self) -> &LiteralExpression {
 
        match self {
 
            Expression::Constant(result) => result,
 
            Expression::Literal(result) => result,
 
            _ => panic!("Unable to cast `Expression` to `ConstantExpression`"),
 
        }
 
    }
 
    pub fn as_call(&self) -> &CallExpression {
 
        match self {
 
            Expression::Call(result) => result,
 
            _ => panic!("Unable to cast `Expression` to `CallExpression`"),
 
        }
 
    }
 
    pub fn as_call_mut(&mut self) -> &mut CallExpression {
 
        match self {
 
            Expression::Call(result) => result,
 
            _ => panic!("Unable to cast `Expression` to `CallExpression`"),
 
        }
 
    }
 
    pub fn as_variable(&self) -> &VariableExpression {
 
        match self {
 
            Expression::Variable(result) => result,
 
            _ => panic!("Unable to cast `Expression` to `VariableExpression`"),
 
        }
 
    }
 
    pub fn as_variable_mut(&mut self) -> &mut VariableExpression {
 
        match self {
 
            Expression::Variable(result) => result,
 
            _ => panic!("Unable to cast `Expression` to `VariableExpression`"),
 
        }
 
    }
 
    // TODO: @cleanup
 
    pub fn parent(&self) -> &ExpressionParent {
 
        match self {
 
            Expression::Assignment(expr) => &expr.parent,
 
            Expression::Conditional(expr) => &expr.parent,
 
            Expression::Binary(expr) => &expr.parent,
 
            Expression::Unary(expr) => &expr.parent,
 
            Expression::Indexing(expr) => &expr.parent,
 
            Expression::Slicing(expr) => &expr.parent,
 
            Expression::Select(expr) => &expr.parent,
 
            Expression::Array(expr) => &expr.parent,
 
            Expression::Constant(expr) => &expr.parent,
 
            Expression::Literal(expr) => &expr.parent,
 
            Expression::Call(expr) => &expr.parent,
 
            Expression::Variable(expr) => &expr.parent,
 
        }
 
    }
 
    // TODO: @cleanup
 
    pub fn parent_expr_id(&self) -> Option<ExpressionId> {
 
        if let ExpressionParent::Expression(id, _) = self.parent() {
 
            Some(*id)
 
        } else {
 
            None
 
        }
 
    }
 
    // TODO: @cleanup
 
    pub fn set_parent(&mut self, parent: ExpressionParent) {
 
        match self {
 
            Expression::Assignment(expr) => expr.parent = parent,
 
            Expression::Conditional(expr) => expr.parent = parent,
 
            Expression::Binary(expr) => expr.parent = parent,
 
            Expression::Unary(expr) => expr.parent = parent,
 
            Expression::Indexing(expr) => expr.parent = parent,
 
            Expression::Slicing(expr) => expr.parent = parent,
 
            Expression::Select(expr) => expr.parent = parent,
 
            Expression::Array(expr) => expr.parent = parent,
 
            Expression::Constant(expr) => expr.parent = parent,
 
            Expression::Literal(expr) => expr.parent = parent,
 
            Expression::Call(expr) => expr.parent = parent,
 
            Expression::Variable(expr) => expr.parent = parent,
 
        }
 
    }
 
    // TODO: @cleanup
 
    pub fn get_type_mut(&mut self) -> &mut ConcreteType {
 
        match self {
 
            Expression::Assignment(expr) => &mut expr.concrete_type,
 
            Expression::Conditional(expr) => &mut expr.concrete_type,
 
            Expression::Binary(expr) => &mut expr.concrete_type,
 
            Expression::Unary(expr) => &mut expr.concrete_type,
 
            Expression::Indexing(expr) => &mut expr.concrete_type,
 
            Expression::Slicing(expr) => &mut expr.concrete_type,
 
            Expression::Select(expr) => &mut expr.concrete_type,
 
            Expression::Array(expr) => &mut expr.concrete_type,
 
            Expression::Constant(expr) => &mut expr.concrete_type,
 
            Expression::Literal(expr) => &mut expr.concrete_type,
 
            Expression::Call(expr) => &mut expr.concrete_type,
 
            Expression::Variable(expr) => &mut expr.concrete_type,
 
        }
 
    }
 
}
 

	
 
impl SyntaxElement for Expression {
 
    fn position(&self) -> InputPosition {
 
        match self {
 
            Expression::Assignment(expr) => expr.position(),
 
            Expression::Conditional(expr) => expr.position(),
 
            Expression::Binary(expr) => expr.position(),
 
            Expression::Unary(expr) => expr.position(),
 
            Expression::Indexing(expr) => expr.position(),
 
            Expression::Slicing(expr) => expr.position(),
 
            Expression::Select(expr) => expr.position(),
 
            Expression::Array(expr) => expr.position(),
 
            Expression::Constant(expr) => expr.position(),
 
            Expression::Literal(expr) => expr.position(),
 
            Expression::Call(expr) => expr.position(),
 
            Expression::Variable(expr) => expr.position(),
 
        }
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum AssignmentOperator {
 
    Set,
 
    Multiplied,
 
    Divided,
 
    Remained,
 
    Added,
 
    Subtracted,
 
    ShiftedLeft,
 
    ShiftedRight,
 
    BitwiseAnded,
 
    BitwiseXored,
 
    BitwiseOred,
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct AssignmentExpression {
 
    pub this: AssignmentExpressionId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub left: ExpressionId,
 
    pub operation: AssignmentOperator,
 
    pub right: ExpressionId,
 
    // Phase 2: linker
 
    pub parent: ExpressionParent,
 
    // Phase 3: type checking
 
    pub concrete_type: ConcreteType,
 
}
 

	
 
impl SyntaxElement for AssignmentExpression {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct ConditionalExpression {
 
    pub this: ConditionalExpressionId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub test: ExpressionId,
 
    pub true_expression: ExpressionId,
 
    pub false_expression: ExpressionId,
 
    // Phase 2: linker
 
    pub parent: ExpressionParent,
 
    // Phase 3: type checking
 
    pub concrete_type: ConcreteType,
 
}
 

	
 
impl SyntaxElement for ConditionalExpression {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
 
pub enum BinaryOperator {
 
    Concatenate,
 
    LogicalOr,
 
    LogicalAnd,
 
    BitwiseOr,
 
    BitwiseXor,
 
    BitwiseAnd,
 
    Equality,
 
    Inequality,
 
    LessThan,
 
    GreaterThan,
 
    LessThanEqual,
 
    GreaterThanEqual,
 
    ShiftLeft,
 
    ShiftRight,
 
    Add,
 
    Subtract,
 
    Multiply,
 
    Divide,
 
    Remainder,
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct BinaryExpression {
 
    pub this: BinaryExpressionId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub left: ExpressionId,
 
    pub operation: BinaryOperator,
 
    pub right: ExpressionId,
 
    // Phase 2: linker
 
    pub parent: ExpressionParent,
 
    // Phase 3: type checking
 
    pub concrete_type: ConcreteType,
 
}
 

	
 
impl SyntaxElement for BinaryExpression {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
 
pub enum UnaryOperation {
 
    Positive,
 
    Negative,
 
    BitwiseNot,
 
    LogicalNot,
 
    PreIncrement,
 
    PreDecrement,
 
    PostIncrement,
 
    PostDecrement,
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct UnaryExpression {
 
    pub this: UnaryExpressionId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub operation: UnaryOperation,
 
    pub expression: ExpressionId,
 
    // Phase 2: linker
 
    pub parent: ExpressionParent,
 
    // Phase 3: type checking
 
    pub concrete_type: ConcreteType,
 
}
 

	
 
impl SyntaxElement for UnaryExpression {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct IndexingExpression {
 
    pub this: IndexingExpressionId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub subject: ExpressionId,
 
    pub index: ExpressionId,
 
    // Phase 2: linker
 
    pub parent: ExpressionParent,
 
    // Phase 3: type checking
 
    pub concrete_type: ConcreteType,
 
}
 

	
 
impl SyntaxElement for IndexingExpression {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct SlicingExpression {
 
    pub this: SlicingExpressionId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub subject: ExpressionId,
 
    pub from_index: ExpressionId,
 
    pub to_index: ExpressionId,
 
    // Phase 2: linker
 
    pub parent: ExpressionParent,
 
    // Phase 3: type checking
 
    pub concrete_type: ConcreteType,
 
}
 

	
 
impl SyntaxElement for SlicingExpression {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct SelectExpression {
 
    pub this: SelectExpressionId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub subject: ExpressionId,
 
    pub field: Field,
 
    // Phase 2: linker
 
    pub parent: ExpressionParent,
 
    // Phase 3: type checking
 
    pub concrete_type: ConcreteType,
 
}
 

	
 
impl SyntaxElement for SelectExpression {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct ArrayExpression {
 
    pub this: ArrayExpressionId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub elements: Vec<ExpressionId>,
 
    // Phase 2: linker
 
    pub parent: ExpressionParent,
 
    // Phase 3: type checking
 
    pub concrete_type: ConcreteType,
 
}
 

	
 
impl SyntaxElement for ArrayExpression {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct CallExpression {
 
    pub this: CallExpressionId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub method: Method,
 
    pub arguments: Vec<ExpressionId>,
 
    pub poly_args: Vec<ParserTypeId>,
 
    // Phase 2: linker
 
    pub parent: ExpressionParent,
 
    // Phase 3: type checking
 
    pub concrete_type: ConcreteType,
 
}
 

	
 
impl SyntaxElement for CallExpression {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct ConstantExpression {
 
    pub this: ConstantExpressionId,
 
pub struct LiteralExpression {
 
    pub this: LiteralExpressionId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub value: Constant,
 
    pub value: Literal,
 
    // Phase 2: linker
 
    pub parent: ExpressionParent,
 
    // Phase 3: type checking
 
    pub concrete_type: ConcreteType,
 
}
 

	
 
impl SyntaxElement for ConstantExpression {
 
impl SyntaxElement for LiteralExpression {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct VariableExpression {
 
    pub this: VariableExpressionId,
 
    // Phase 1: parser
 
    pub position: InputPosition,
 
    pub identifier: NamespacedIdentifier,
 
    // Phase 2: linker
 
    pub declaration: Option<VariableId>,
 
    pub parent: ExpressionParent,
 
    // Phase 3: type checking
 
    pub concrete_type: ConcreteType,
 
}
 

	
 
impl SyntaxElement for VariableExpression {
 
    fn position(&self) -> InputPosition {
 
        self.position
 
    }
 
}
src/protocol/ast_printer.rs
Show inline comments
 
@@ -231,605 +231,605 @@ impl ASTWriter {
 
        let import = &heap[import_id];
 
        let indent2 = indent + 1;
 

	
 
        match import {
 
            Import::Module(import) => {
 
                self.kv(indent).with_id(PREFIX_IMPORT_ID, import.this.index)
 
                    .with_s_key("ImportModule");
 

	
 
                self.kv(indent2).with_s_key("Name").with_ascii_val(&import.module_name);
 
                self.kv(indent2).with_s_key("Alias").with_ascii_val(&import.alias);
 
                self.kv(indent2).with_s_key("Target")
 
                    .with_opt_disp_val(import.module_id.as_ref().map(|v| &v.index));
 
            },
 
            Import::Symbols(import) => {
 
                self.kv(indent).with_id(PREFIX_IMPORT_ID, import.this.index)
 
                    .with_s_key("ImportSymbol");
 

	
 
                self.kv(indent2).with_s_key("Name").with_ascii_val(&import.module_name);
 
                self.kv(indent2).with_s_key("Target")
 
                    .with_opt_disp_val(import.module_id.as_ref().map(|v| &v.index));
 

	
 
                self.kv(indent2).with_s_key("Symbols");
 

	
 
                let indent3 = indent2 + 1;
 
                let indent4 = indent3 + 1;
 
                for symbol in &import.symbols {
 
                    self.kv(indent3).with_s_key("AliasedSymbol");
 
                    self.kv(indent4).with_s_key("Name").with_ascii_val(&symbol.name);
 
                    self.kv(indent4).with_s_key("Alias").with_ascii_val(&symbol.alias);
 
                    self.kv(indent4).with_s_key("Definition")
 
                        .with_opt_disp_val(symbol.definition_id.as_ref().map(|v| &v.index));
 
                }
 
            }
 
        }
 
    }
 

	
 
    //--------------------------------------------------------------------------
 
    // Top-level definition writing
 
    //--------------------------------------------------------------------------
 

	
 
    fn write_definition(&mut self, heap: &Heap, def_id: DefinitionId, indent: usize) {
 
        self.cur_definition = Some(def_id);
 
        let indent2 = indent + 1;
 
        let indent3 = indent2 + 1;
 
        let indent4 = indent3 + 1;
 

	
 
        match &heap[def_id] {
 
            Definition::Struct(_) => todo!("implement Definition::Struct"),
 
            Definition::Enum(_) => todo!("implement Definition::Enum"),
 
            Definition::Function(def) => {
 
                self.kv(indent).with_id(PREFIX_FUNCTION_ID, def.this.0.index)
 
                    .with_s_key("DefinitionFunction");
 

	
 
                self.kv(indent2).with_s_key("Name").with_ascii_val(&def.identifier.value);
 
                for poly_var_id in &def.poly_vars {
 
                    self.kv(indent3).with_s_key("PolyVar");
 
                    self.kv(indent4).with_s_key("Name").with_ascii_val(&poly_var_id.value);
 
                }
 

	
 
                self.kv(indent2).with_s_key("ReturnParserType").with_custom_val(|s| write_parser_type(s, heap, &heap[def.return_type]));
 

	
 
                self.kv(indent2).with_s_key("Parameters");
 
                for param_id in &def.parameters {
 
                    self.write_parameter(heap, *param_id, indent3);
 
                }
 

	
 
                self.kv(indent2).with_s_key("Body");
 
                self.write_stmt(heap, def.body, indent3);
 
            },
 
            Definition::Component(def) => {
 
                self.kv(indent).with_id(PREFIX_COMPONENT_ID,def.this.0.index)
 
                    .with_s_key("DefinitionComponent");
 

	
 
                self.kv(indent2).with_s_key("Name").with_ascii_val(&def.identifier.value);
 
                self.kv(indent2).with_s_key("Variant").with_debug_val(&def.variant);
 

	
 
                self.kv(indent2).with_s_key("PolymorphicVariables");
 
                for poly_var_id in &def.poly_vars {
 
                    self.kv(indent3).with_s_key("PolyVar");
 
                    self.kv(indent4).with_s_key("Name").with_ascii_val(&poly_var_id.value);
 
                }
 

	
 
                self.kv(indent2).with_s_key("Parameters");
 
                for param_id in &def.parameters {
 
                    self.write_parameter(heap, *param_id, indent3)
 
                }
 

	
 
                self.kv(indent2).with_s_key("Body");
 
                self.write_stmt(heap, def.body, indent3);
 
            }
 
        }
 
    }
 

	
 
    fn write_parameter(&mut self, heap: &Heap, param_id: ParameterId, indent: usize) {
 
        let indent2 = indent + 1;
 
        let param = &heap[param_id];
 

	
 
        self.kv(indent).with_id(PREFIX_PARAMETER_ID, param_id.0.index)
 
            .with_s_key("Parameter");
 
        self.kv(indent2).with_s_key("Name").with_ascii_val(&param.identifier.value);
 
        self.kv(indent2).with_s_key("ParserType").with_custom_val(|w| write_parser_type(w, heap, &heap[param.parser_type]));
 
    }
 

	
 
    fn write_stmt(&mut self, heap: &Heap, stmt_id: StatementId, indent: usize) {
 
        let stmt = &heap[stmt_id];
 
        let indent2 = indent + 1;
 
        let indent3 = indent2 + 1;
 

	
 
        match stmt {
 
            Statement::Block(stmt) => {
 
                self.kv(indent).with_id(PREFIX_BLOCK_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("Block");
 

	
 
                for stmt_id in &stmt.statements {
 
                    self.write_stmt(heap, *stmt_id, indent2);
 
                }
 
            },
 
            Statement::Local(stmt) => {
 
                match stmt {
 
                    LocalStatement::Channel(stmt) => {
 
                        self.kv(indent).with_id(PREFIX_CHANNEL_STMT_ID, stmt.this.0.0.index)
 
                            .with_s_key("LocalChannel");
 

	
 
                        self.kv(indent2).with_s_key("From");
 
                        self.write_local(heap, stmt.from, indent3);
 
                        self.kv(indent2).with_s_key("To");
 
                        self.write_local(heap, stmt.to, indent3);
 
                        self.kv(indent2).with_s_key("Next")
 
                            .with_opt_disp_val(stmt.next.as_ref().map(|v| &v.index));
 
                    },
 
                    LocalStatement::Memory(stmt) => {
 
                        self.kv(indent).with_id(PREFIX_MEM_STMT_ID, stmt.this.0.0.index)
 
                            .with_s_key("LocalMemory");
 

	
 
                        self.kv(indent2).with_s_key("Variable");
 
                        self.write_local(heap, stmt.variable, indent3);
 
                        self.kv(indent2).with_s_key("Next")
 
                            .with_opt_disp_val(stmt.next.as_ref().map(|v| &v.index));
 
                    }
 
                }
 
            },
 
            Statement::Skip(stmt) => {
 
                self.kv(indent).with_id(PREFIX_SKIP_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("Skip");
 
                self.kv(indent2).with_s_key("Next")
 
                    .with_opt_disp_val(stmt.next.as_ref().map(|v| &v.index));
 
            },
 
            Statement::Labeled(stmt) => {
 
                self.kv(indent).with_id(PREFIX_LABELED_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("Labeled");
 

	
 
                self.kv(indent2).with_s_key("Label").with_ascii_val(&stmt.label.value);
 
                self.kv(indent2).with_s_key("Statement");
 
                self.write_stmt(heap, stmt.body, indent3);
 
            },
 
            Statement::If(stmt) => {
 
                self.kv(indent).with_id(PREFIX_IF_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("If");
 

	
 
                self.kv(indent2).with_s_key("EndIf")
 
                    .with_opt_disp_val(stmt.end_if.as_ref().map(|v| &v.0.index));
 

	
 
                self.kv(indent2).with_s_key("Condition");
 
                self.write_expr(heap, stmt.test, indent3);
 

	
 
                self.kv(indent2).with_s_key("TrueBody");
 
                self.write_stmt(heap, stmt.true_body, indent3);
 

	
 
                self.kv(indent2).with_s_key("FalseBody");
 
                self.write_stmt(heap, stmt.false_body, indent3);
 
            },
 
            Statement::EndIf(stmt) => {
 
                self.kv(indent).with_id(PREFIX_ENDIF_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("EndIf");
 
                self.kv(indent2).with_s_key("StartIf").with_disp_val(&stmt.start_if.0.index);
 
                self.kv(indent2).with_s_key("Next")
 
                    .with_opt_disp_val(stmt.next.as_ref().map(|v| &v.index));
 
            },
 
            Statement::While(stmt) => {
 
                self.kv(indent).with_id(PREFIX_WHILE_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("While");
 

	
 
                self.kv(indent2).with_s_key("EndWhile")
 
                    .with_opt_disp_val(stmt.end_while.as_ref().map(|v| &v.0.index));
 
                self.kv(indent2).with_s_key("InSync")
 
                    .with_opt_disp_val(stmt.in_sync.as_ref().map(|v| &v.0.index));
 
                self.kv(indent2).with_s_key("Condition");
 
                self.write_expr(heap, stmt.test, indent3);
 
                self.kv(indent2).with_s_key("Body");
 
                self.write_stmt(heap, stmt.body, indent3);
 
            },
 
            Statement::EndWhile(stmt) => {
 
                self.kv(indent).with_id(PREFIX_ENDWHILE_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("EndWhile");
 
                self.kv(indent2).with_s_key("StartWhile").with_disp_val(&stmt.start_while.0.index);
 
                self.kv(indent2).with_s_key("Next")
 
                    .with_opt_disp_val(stmt.next.as_ref().map(|v| &v.index));
 
            },
 
            Statement::Break(stmt) => {
 
                self.kv(indent).with_id(PREFIX_BREAK_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("Break");
 
                self.kv(indent2).with_s_key("Label")
 
                    .with_opt_ascii_val(stmt.label.as_ref().map(|v| v.value.as_slice()));
 
                self.kv(indent2).with_s_key("Target")
 
                    .with_opt_disp_val(stmt.target.as_ref().map(|v| &v.0.index));
 
            },
 
            Statement::Continue(stmt) => {
 
                self.kv(indent).with_id(PREFIX_CONTINUE_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("Continue");
 
                self.kv(indent2).with_s_key("Label")
 
                    .with_opt_ascii_val(stmt.label.as_ref().map(|v| v.value.as_slice()));
 
                self.kv(indent2).with_s_key("Target")
 
                    .with_opt_disp_val(stmt.target.as_ref().map(|v| &v.0.index));
 
            },
 
            Statement::Synchronous(stmt) => {
 
                self.kv(indent).with_id(PREFIX_SYNC_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("Synchronous");
 
                self.kv(indent2).with_s_key("EndSync")
 
                    .with_opt_disp_val(stmt.end_sync.as_ref().map(|v| &v.0.index));
 
                self.kv(indent2).with_s_key("Body");
 
                self.write_stmt(heap, stmt.body, indent3);
 
            },
 
            Statement::EndSynchronous(stmt) => {
 
                self.kv(indent).with_id(PREFIX_ENDSYNC_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("EndSynchronous");
 
                self.kv(indent2).with_s_key("StartSync").with_disp_val(&stmt.start_sync.0.index);
 
                self.kv(indent2).with_s_key("Next")
 
                    .with_opt_disp_val(stmt.next.as_ref().map(|v| &v.index));
 
            },
 
            Statement::Return(stmt) => {
 
                self.kv(indent).with_id(PREFIX_RETURN_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("Return");
 
                self.kv(indent2).with_s_key("Expression");
 
                self.write_expr(heap, stmt.expression, indent3);
 
            },
 
            Statement::Assert(stmt) => {
 
                self.kv(indent).with_id(PREFIX_ASSERT_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("Assert");
 
                self.kv(indent2).with_s_key("Expression");
 
                self.write_expr(heap, stmt.expression, indent3);
 
                self.kv(indent2).with_s_key("Next")
 
                    .with_opt_disp_val(stmt.next.as_ref().map(|v| &v.index));
 
            },
 
            Statement::Goto(stmt) => {
 
                self.kv(indent).with_id(PREFIX_GOTO_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("Goto");
 
                self.kv(indent2).with_s_key("Label").with_ascii_val(&stmt.label.value);
 
                self.kv(indent2).with_s_key("Target")
 
                    .with_opt_disp_val(stmt.target.as_ref().map(|v| &v.0.index));
 
            },
 
            Statement::New(stmt) => {
 
                self.kv(indent).with_id(PREFIX_NEW_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("New");
 
                self.kv(indent2).with_s_key("Expression");
 
                self.write_expr(heap, stmt.expression.upcast(), indent3);
 
                self.kv(indent2).with_s_key("Next")
 
                    .with_opt_disp_val(stmt.next.as_ref().map(|v| &v.index));
 
            },
 
            Statement::Expression(stmt) => {
 
                self.kv(indent).with_id(PREFIX_EXPR_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("ExpressionStatement");
 
                self.write_expr(heap, stmt.expression, indent2);
 
                self.kv(indent2).with_s_key("Next")
 
                    .with_opt_disp_val(stmt.next.as_ref().map(|v| &v.index));
 
            }
 
        }
 
    }
 

	
 
    fn write_expr(&mut self, heap: &Heap, expr_id: ExpressionId, indent: usize) {
 
        let expr = &heap[expr_id];
 
        let indent2 = indent + 1;
 
        let indent3 = indent2 + 1;
 
        let def_id = self.cur_definition.unwrap();
 

	
 
        match expr {
 
            Expression::Assignment(expr) => {
 
                self.kv(indent).with_id(PREFIX_ASSIGNMENT_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("AssignmentExpr");
 
                self.kv(indent2).with_s_key("Operation").with_debug_val(&expr.operation);
 
                self.kv(indent2).with_s_key("Left");
 
                self.write_expr(heap, expr.left, indent3);
 
                self.kv(indent2).with_s_key("Right");
 
                self.write_expr(heap, expr.right, indent3);
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
                self.kv(indent2).with_s_key("ConcreteType")
 
                    .with_custom_val(|v| write_concrete_type(v, heap, def_id, &expr.concrete_type));
 
            },
 
            Expression::Conditional(expr) => {
 
                self.kv(indent).with_id(PREFIX_CONDITIONAL_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("ConditionalExpr");
 
                self.kv(indent2).with_s_key("Condition");
 
                self.write_expr(heap, expr.test, indent3);
 
                self.kv(indent2).with_s_key("TrueExpression");
 
                self.write_expr(heap, expr.true_expression, indent3);
 
                self.kv(indent2).with_s_key("FalseExpression");
 
                self.write_expr(heap, expr.false_expression, indent3);
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
                self.kv(indent2).with_s_key("ConcreteType")
 
                    .with_custom_val(|v| write_concrete_type(v, heap, def_id, &expr.concrete_type));
 
            },
 
            Expression::Binary(expr) => {
 
                self.kv(indent).with_id(PREFIX_BINARY_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("BinaryExpr");
 
                self.kv(indent2).with_s_key("Operation").with_debug_val(&expr.operation);
 
                self.kv(indent2).with_s_key("Left");
 
                self.write_expr(heap, expr.left, indent3);
 
                self.kv(indent2).with_s_key("Right");
 
                self.write_expr(heap, expr.right, indent3);
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
                self.kv(indent2).with_s_key("ConcreteType")
 
                    .with_custom_val(|v| write_concrete_type(v, heap, def_id, &expr.concrete_type));
 
            },
 
            Expression::Unary(expr) => {
 
                self.kv(indent).with_id(PREFIX_UNARY_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("UnaryExpr");
 
                self.kv(indent2).with_s_key("Operation").with_debug_val(&expr.operation);
 
                self.kv(indent2).with_s_key("Argument");
 
                self.write_expr(heap, expr.expression, indent3);
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
                self.kv(indent2).with_s_key("ConcreteType")
 
                    .with_custom_val(|v| write_concrete_type(v, heap, def_id, &expr.concrete_type));
 
            },
 
            Expression::Indexing(expr) => {
 
                self.kv(indent).with_id(PREFIX_INDEXING_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("IndexingExpr");
 
                self.kv(indent2).with_s_key("Subject");
 
                self.write_expr(heap, expr.subject, indent3);
 
                self.kv(indent2).with_s_key("Index");
 
                self.write_expr(heap, expr.index, indent3);
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
                self.kv(indent2).with_s_key("ConcreteType")
 
                    .with_custom_val(|v| write_concrete_type(v, heap, def_id, &expr.concrete_type));
 
            },
 
            Expression::Slicing(expr) => {
 
                self.kv(indent).with_id(PREFIX_SLICING_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("SlicingExpr");
 
                self.kv(indent2).with_s_key("Subject");
 
                self.write_expr(heap, expr.subject, indent3);
 
                self.kv(indent2).with_s_key("FromIndex");
 
                self.write_expr(heap, expr.from_index, indent3);
 
                self.kv(indent2).with_s_key("ToIndex");
 
                self.write_expr(heap, expr.to_index, indent3);
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
                self.kv(indent2).with_s_key("ConcreteType")
 
                    .with_custom_val(|v| write_concrete_type(v, heap, def_id, &expr.concrete_type));
 
            },
 
            Expression::Select(expr) => {
 
                self.kv(indent).with_id(PREFIX_SELECT_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("SelectExpr");
 
                self.kv(indent2).with_s_key("Subject");
 
                self.write_expr(heap, expr.subject, indent3);
 

	
 
                match &expr.field {
 
                    Field::Length => {
 
                        self.kv(indent2).with_s_key("Field").with_s_val("length");
 
                    },
 
                    Field::Symbolic(field) => {
 
                        self.kv(indent2).with_s_key("Field").with_ascii_val(&field.value);
 
                    }
 
                }
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
                self.kv(indent2).with_s_key("ConcreteType")
 
                    .with_custom_val(|v| write_concrete_type(v, heap, def_id, &expr.concrete_type));
 
            },
 
            Expression::Array(expr) => {
 
                self.kv(indent).with_id(PREFIX_ARRAY_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("ArrayExpr");
 
                self.kv(indent2).with_s_key("Elements");
 
                for expr_id in &expr.elements {
 
                    self.write_expr(heap, *expr_id, indent3);
 
                }
 

	
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
                self.kv(indent2).with_s_key("ConcreteType")
 
                    .with_custom_val(|v| write_concrete_type(v, heap, def_id, &expr.concrete_type));
 
            },
 
            Expression::Constant(expr) => {
 
            Expression::Literal(expr) => {
 
                self.kv(indent).with_id(PREFIX_CONST_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("ConstantExpr");
 

	
 
                let val = self.kv(indent2).with_s_key("Value");
 
                match &expr.value {
 
                    Constant::Null => { val.with_s_val("null"); },
 
                    Constant::True => { val.with_s_val("true"); },
 
                    Constant::False => { val.with_s_val("false"); },
 
                    Constant::Character(char) => { val.with_ascii_val(char); },
 
                    Constant::Integer(int) => { val.with_disp_val(int); },
 
                    Literal::Null => { val.with_s_val("null"); },
 
                    Literal::True => { val.with_s_val("true"); },
 
                    Literal::False => { val.with_s_val("false"); },
 
                    Literal::Character(char) => { val.with_ascii_val(char); },
 
                    Literal::Integer(int) => { val.with_disp_val(int); },
 
                }
 

	
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
                self.kv(indent2).with_s_key("ConcreteType")
 
                    .with_custom_val(|v| write_concrete_type(v, heap, def_id, &expr.concrete_type));
 
            },
 
            Expression::Call(expr) => {
 
                self.kv(indent).with_id(PREFIX_CALL_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("CallExpr");
 

	
 
                // Method
 
                let method = self.kv(indent2).with_s_key("Method");
 
                match &expr.method {
 
                    Method::Get => { method.with_s_val("get"); },
 
                    Method::Put => { method.with_s_val("put"); },
 
                    Method::Fires => { method.with_s_val("fires"); },
 
                    Method::Create => { method.with_s_val("create"); },
 
                    Method::Symbolic(symbolic) => {
 
                        method.with_s_val("symbolic");
 
                        self.kv(indent3).with_s_key("Name").with_ascii_val(&symbolic.identifier.value);
 
                        self.kv(indent3).with_s_key("Definition")
 
                            .with_opt_disp_val(symbolic.definition.as_ref().map(|v| &v.index));
 
                    }
 
                }
 

	
 
                // Arguments
 
                self.kv(indent2).with_s_key("Arguments");
 
                for arg_id in &expr.arguments {
 
                    self.write_expr(heap, *arg_id, indent3);
 
                }
 

	
 
                // Parent
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
                self.kv(indent2).with_s_key("ConcreteType")
 
                    .with_custom_val(|v| write_concrete_type(v, heap, def_id, &expr.concrete_type));
 
            },
 
            Expression::Variable(expr) => {
 
                self.kv(indent).with_id(PREFIX_VARIABLE_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("VariableExpr");
 
                self.kv(indent2).with_s_key("Name").with_ascii_val(&expr.identifier.value);
 
                self.kv(indent2).with_s_key("Definition")
 
                    .with_opt_disp_val(expr.declaration.as_ref().map(|v| &v.index));
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
                self.kv(indent2).with_s_key("ConcreteType")
 
                    .with_custom_val(|v| write_concrete_type(v, heap, def_id, &expr.concrete_type));
 
            }
 
        }
 
    }
 

	
 
    fn write_local(&mut self, heap: &Heap, local_id: LocalId, indent: usize) {
 
        let local = &heap[local_id];
 
        let indent2 = indent + 1;
 

	
 
        self.kv(indent).with_id(PREFIX_LOCAL_ID, local_id.0.index)
 
            .with_s_key("Local");
 

	
 
        self.kv(indent2).with_s_key("Name").with_ascii_val(&local.identifier.value);
 
        self.kv(indent2).with_s_key("ParserType")
 
            .with_custom_val(|w| write_parser_type(w, heap, &heap[local.parser_type]));
 
    }
 

	
 
    //--------------------------------------------------------------------------
 
    // Printing Utilities
 
    //--------------------------------------------------------------------------
 

	
 
    fn kv(&mut self, indent: usize) -> KV {
 
        KV::new(&mut self.buffer, &mut self.temp1, &mut self.temp2, indent)
 
    }
 

	
 
    fn flush<W: IOWrite>(&mut self, w: &mut W) {
 
        w.write(self.buffer.as_bytes()).unwrap();
 
        self.buffer.clear()
 
    }
 
}
 

	
 
fn write_option<V: Display>(target: &mut String, value: Option<V>) {
 
    target.clear();
 
    match &value {
 
        Some(v) => target.push_str(&format!("Some({})", v)),
 
        None => target.push_str("None")
 
    };
 
}
 

	
 
fn write_parser_type(target: &mut String, heap: &Heap, t: &ParserType) {
 
    use ParserTypeVariant as PTV;
 

	
 
    let mut embedded = Vec::new();
 
    match &t.variant {
 
        PTV::Input(id) => { target.push_str("in"); embedded.push(*id); }
 
        PTV::Output(id) => { target.push_str("out"); embedded.push(*id) }
 
        PTV::Array(id) => { target.push_str("array"); embedded.push(*id) }
 
        PTV::Message => { target.push_str("msg"); }
 
        PTV::Bool => { target.push_str("bool"); }
 
        PTV::Byte => { target.push_str("byte"); }
 
        PTV::Short => { target.push_str("short"); }
 
        PTV::Int => { target.push_str("int"); }
 
        PTV::Long => { target.push_str("long"); }
 
        PTV::String => { target.push_str("str"); }
 
        PTV::IntegerLiteral => { target.push_str("int_lit"); }
 
        PTV::Inferred => { target.push_str("auto"); }
 
        PTV::Symbolic(symbolic) => {
 
            target.push_str(&String::from_utf8_lossy(&symbolic.identifier.value));
 
            match symbolic.variant {
 
                Some(SymbolicParserTypeVariant::PolyArg(def_id, idx)) => {
 
                    target.push_str(&format!("{{def: {}, idx: {}}}", def_id.index, idx));
 
                },
 
                Some(SymbolicParserTypeVariant::Definition(def_id)) => {
 
                    target.push_str(&format!("{{def: {}}}", def_id.index));
 
                },
 
                None => {
 
                    target.push_str("{None}");
 
                }
 
            }
 
            embedded.extend(&symbolic.poly_args);
 
        }
 
    };
 

	
 
    if !embedded.is_empty() {
 
        target.push_str("<");
 
        for (idx, embedded_id) in embedded.into_iter().enumerate() {
 
            if idx != 0 { target.push_str(", "); }
 
            write_parser_type(target, heap, &heap[embedded_id]);
 
        }
 
        target.push_str(">");
 
    }
 
}
 

	
 
fn write_concrete_type(target: &mut String, heap: &Heap, def_id: DefinitionId, t: &ConcreteType) {
 
    use ConcreteTypePart as CTP;
 

	
 
    fn write_concrete_part(target: &mut String, heap: &Heap, def_id: DefinitionId, t: &ConcreteType, mut idx: usize) -> usize {
 
        if idx >= t.parts.len() {
 
            return idx;
 
        }
 

	
 
        match &t.parts[idx] {
 
            CTP::Marker(marker) => {
 
                // Marker points to polymorphic variable index
 
                let definition = &heap[def_id];
 
                let poly_var_ident = match definition {
 
                    Definition::Struct(_) | Definition::Enum(_) => unreachable!(),
 
                    Definition::Function(definition) => &definition.poly_vars[*marker].value,
 
                    Definition::Component(definition) => &definition.poly_vars[*marker].value,
 
                };
 
                target.push_str(&String::from_utf8_lossy(&poly_var_ident));
 
                idx = write_concrete_part(target, heap, def_id, t, idx + 1);
 
            },
 
            CTP::Void => target.push_str("void"),
 
            CTP::Message => target.push_str("msg"),
 
            CTP::Bool => target.push_str("bool"),
 
            CTP::Byte => target.push_str("byte"),
 
            CTP::Short => target.push_str("short"),
 
            CTP::Int => target.push_str("int"),
 
            CTP::Long => target.push_str("long"),
 
            CTP::String => target.push_str("string"),
 
            CTP::Array => {
 
                idx = write_concrete_part(target, heap, def_id, t, idx + 1);
 
                target.push_str("[]");
 
            },
 
            CTP::Slice => {
 
                idx = write_concrete_part(target, heap, def_id, t, idx + 1);
 
                target.push_str("[..]");
 
            }
 
            CTP::Input => {
 
                target.push_str("in<");
 
                idx = write_concrete_part(target, heap, def_id, t, idx + 1);
 
                target.push('>');
 
            },
 
            CTP::Output => {
 
                target.push_str("out<");
 
                idx = write_concrete_part(target, heap, def_id, t, idx + 1);
 
                target.push('>')
 
            },
 
            CTP::Instance(definition_id, num_embedded) => {
 
                let identifier = heap[*definition_id].identifier();
 
                target.push_str(&String::from_utf8_lossy(&identifier.value));
 
                target.push('<');
 
                for idx_embedded in 0..*num_embedded {
 
                    if idx_embedded != 0 {
 
                        target.push_str(", ");
 
                    }
 
                    idx = write_concrete_part(target, heap, def_id, t, idx + 1);
 
                }
 
                target.push('>');
 
            }
 
        }
 

	
 
        idx + 1
 
    }
 

	
 
    write_concrete_part(target, heap, def_id, t, 0);
 
}
 

	
 
fn write_expression_parent(target: &mut String, parent: &ExpressionParent) {
 
    use ExpressionParent as EP;
 

	
 
    *target = match parent {
 
        EP::None => String::from("None"),
 
        EP::If(id) => format!("IfStmt({})", id.0.index),
 
        EP::While(id) => format!("WhileStmt({})", id.0.index),
 
        EP::Return(id) => format!("ReturnStmt({})", id.0.index),
 
        EP::Assert(id) => format!("AssertStmt({})", id.0.index),
 
        EP::New(id) => format!("NewStmt({})", id.0.index),
 
        EP::ExpressionStmt(id) => format!("ExprStmt({})", id.0.index),
 
        EP::Expression(id, idx) => format!("Expr({}, {})", id.index, idx)
 
    };
 
}
 
\ No newline at end of file
src/protocol/eval.rs
Show inline comments
 
use std::collections::HashMap;
 
use std::fmt;
 
use std::fmt::{Debug, Display, Formatter};
 
use std::{i16, i32, i64, i8};
 

	
 
use crate::common::*;
 

	
 
use crate::protocol::ast::*;
 
use crate::protocol::EvalContext;
 

	
 
// const MAX_RECURSION: usize = 1024;
 

	
 
const BYTE_MIN: i64 = i8::MIN as i64;
 
const BYTE_MAX: i64 = i8::MAX as i64;
 
const SHORT_MIN: i64 = i16::MIN as i64;
 
const SHORT_MAX: i64 = i16::MAX as i64;
 
const INT_MIN: i64 = i32::MIN as i64;
 
const INT_MAX: i64 = i32::MAX as i64;
 

	
 
const MESSAGE_MAX_LENGTH: i64 = SHORT_MAX;
 

	
 
const ONE: Value = Value::Byte(ByteValue(1));
 

	
 
// TODO: All goes one day anyway, so dirty typechecking hack
 
trait ValueImpl {
 
    fn exact_type(&self) -> Type;
 
    fn is_type_compatible(&self, h: &Heap, t: &ParserType) -> bool {
 
        Self::is_type_compatible_hack(h, t)
 
    }
 
    fn is_type_compatible_hack(h: &Heap, t: &ParserType) -> bool;
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub enum Value {
 
    Unassigned,
 
    Input(InputValue),
 
    Output(OutputValue),
 
    Message(MessageValue),
 
    Boolean(BooleanValue),
 
    Byte(ByteValue),
 
    Short(ShortValue),
 
    Int(IntValue),
 
    Long(LongValue),
 
    InputArray(InputArrayValue),
 
    OutputArray(OutputArrayValue),
 
    MessageArray(MessageArrayValue),
 
    BooleanArray(BooleanArrayValue),
 
    ByteArray(ByteArrayValue),
 
    ShortArray(ShortArrayValue),
 
    IntArray(IntArrayValue),
 
    LongArray(LongArrayValue),
 
}
 
impl Value {
 
    pub fn receive_message(buffer: &Payload) -> Value {
 
        Value::Message(MessageValue(Some(buffer.clone())))
 
    }
 
    fn create_message(length: Value) -> Value {
 
        match length {
 
            Value::Byte(_) | Value::Short(_) | Value::Int(_) | Value::Long(_) => {
 
                let length: i64 = i64::from(length);
 
                if length < 0 || length > MESSAGE_MAX_LENGTH {
 
                    // Only messages within the expected length are allowed
 
                    Value::Message(MessageValue(None))
 
                } else {
 
                    Value::Message(MessageValue(Some(Payload::new(length as usize))))
 
                }
 
            }
 
            _ => unimplemented!(),
 
        }
 
    }
 
    fn from_constant(constant: &Constant) -> Value {
 
    fn from_constant(constant: &Literal) -> Value {
 
        match constant {
 
            Constant::Null => Value::Message(MessageValue(None)),
 
            Constant::True => Value::Boolean(BooleanValue(true)),
 
            Constant::False => Value::Boolean(BooleanValue(false)),
 
            Constant::Integer(val) => {
 
            Literal::Null => Value::Message(MessageValue(None)),
 
            Literal::True => Value::Boolean(BooleanValue(true)),
 
            Literal::False => Value::Boolean(BooleanValue(false)),
 
            Literal::Integer(val) => {
 
                // Convert raw ASCII data to UTF-8 string
 
                let val = *val;
 
                if val >= BYTE_MIN && val <= BYTE_MAX {
 
                    Value::Byte(ByteValue(val as i8))
 
                } else if val >= SHORT_MIN && val <= SHORT_MAX {
 
                    Value::Short(ShortValue(val as i16))
 
                } else if val >= INT_MIN && val <= INT_MAX {
 
                    Value::Int(IntValue(val as i32))
 
                } else {
 
                    Value::Long(LongValue(val))
 
                }
 
            }
 
            Constant::Character(_data) => unimplemented!(),
 
            Literal::Character(_data) => unimplemented!(),
 
        }
 
    }
 
    fn set(&mut self, index: &Value, value: &Value) -> Option<Value> {
 
        // The index must be of integer type, and non-negative
 
        let the_index: usize;
 
        match index {
 
            Value::Byte(_) | Value::Short(_) | Value::Int(_) | Value::Long(_) => {
 
                let index = i64::from(index);
 
                if index < 0 || index >= MESSAGE_MAX_LENGTH {
 
                    // It is inconsistent to update out of bounds
 
                    return None;
 
                }
 
                the_index = index.try_into().unwrap();
 
            }
 
            _ => unreachable!(),
 
        }
 
        // The subject must be either a message or an array
 
        // And the value and the subject must be compatible
 
        match (self, value) {
 
            (Value::Message(MessageValue(None)), _) => {
 
                // It is inconsistent to update the null message
 
                None
 
            }
 
            (Value::Message(MessageValue(Some(payload))), Value::Byte(ByteValue(b))) => {
 
                if *b < 0 {
 
                    // It is inconsistent to update with a negative value
 
                    return None;
 
                }
 
                if let Some(slot) = payload.as_mut_vec().get_mut(the_index) {
 
                    *slot = (*b).try_into().unwrap();
 
                    Some(value.clone())
 
                } else {
 
                    // It is inconsistent to update out of bounds
 
                    None
 
                }
 
            }
 
            (Value::Message(MessageValue(Some(payload))), Value::Short(ShortValue(b))) => {
 
                if *b < 0 || *b > BYTE_MAX as i16 {
 
                    // It is inconsistent to update with a negative value or a too large value
 
                    return None;
 
                }
 
                if let Some(slot) = payload.as_mut_vec().get_mut(the_index) {
 
                    *slot = (*b).try_into().unwrap();
 
                    Some(value.clone())
 
                } else {
 
                    // It is inconsistent to update out of bounds
 
                    None
 
                }
 
            }
 
            (Value::InputArray(_), Value::Input(_)) => todo!(),
 
            (Value::OutputArray(_), Value::Output(_)) => todo!(),
 
            (Value::MessageArray(_), Value::Message(_)) => todo!(),
 
            (Value::BooleanArray(_), Value::Boolean(_)) => todo!(),
 
            (Value::ByteArray(_), Value::Byte(_)) => todo!(),
 
            (Value::ShortArray(_), Value::Short(_)) => todo!(),
 
            (Value::IntArray(_), Value::Int(_)) => todo!(),
 
            (Value::LongArray(_), Value::Long(_)) => todo!(),
 
            _ => unreachable!(),
 
        }
 
    }
 
    fn get(&self, index: &Value) -> Option<Value> {
 
        // The index must be of integer type, and non-negative
 
        let the_index: usize;
 
        match index {
 
            Value::Byte(_) | Value::Short(_) | Value::Int(_) | Value::Long(_) => {
 
                let index = i64::from(index);
 
                if index < 0 || index >= MESSAGE_MAX_LENGTH {
 
                    // It is inconsistent to update out of bounds
 
                    return None;
 
                }
 
                the_index = index.try_into().unwrap();
 
            }
 
            _ => unreachable!(),
 
        }
 
        // The subject must be either a message or an array
 
        match self {
 
            Value::Message(MessageValue(None)) => {
 
                // It is inconsistent to read from the null message
 
                None
 
            }
 
            Value::Message(MessageValue(Some(payload))) => {
 
                if let Some(slot) = payload.as_slice().get(the_index) {
 
                    Some(Value::Short(ShortValue((*slot).try_into().unwrap())))
 
                } else {
 
                    // It is inconsistent to update out of bounds
 
                    None
 
                }
 
            }
 
            _ => panic!("Can only get from port value"),
 
        }
 
    }
 
    fn length(&self) -> Option<Value> {
 
        // The subject must be either a message or an array
 
        match self {
 
            Value::Message(MessageValue(None)) => {
 
                // It is inconsistent to get length from the null message
 
                None
 
            }
 
            Value::Message(MessageValue(Some(buffer))) => {
 
                Some(Value::Int(IntValue((buffer.len()).try_into().unwrap())))
 
            }
 
            Value::InputArray(InputArrayValue(vec)) => {
 
                Some(Value::Int(IntValue((vec.len()).try_into().unwrap())))
 
            }
 
            Value::OutputArray(OutputArrayValue(vec)) => {
 
                Some(Value::Int(IntValue((vec.len()).try_into().unwrap())))
 
            }
 
            Value::MessageArray(MessageArrayValue(vec)) => {
 
                Some(Value::Int(IntValue((vec.len()).try_into().unwrap())))
 
            }
 
            Value::BooleanArray(BooleanArrayValue(vec)) => {
 
                Some(Value::Int(IntValue((vec.len()).try_into().unwrap())))
 
            }
 
            Value::ByteArray(ByteArrayValue(vec)) => {
 
                Some(Value::Int(IntValue((vec.len()).try_into().unwrap())))
 
            }
 
            Value::ShortArray(ShortArrayValue(vec)) => {
 
                Some(Value::Int(IntValue((vec.len()).try_into().unwrap())))
 
            }
 
            Value::IntArray(IntArrayValue(vec)) => {
 
                Some(Value::Int(IntValue((vec.len()).try_into().unwrap())))
 
            }
 
            Value::LongArray(LongArrayValue(vec)) => {
 
                Some(Value::Int(IntValue((vec.len()).try_into().unwrap())))
 
            }
 
            _ => unreachable!(),
 
        }
 
    }
 
    fn plus(&self, other: &Value) -> Value {
 
        match (self, other) {
 
            (Value::Byte(ByteValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Byte(ByteValue(*s + *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Short(ShortValue(*s as i16 + *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Int(IntValue(*s as i32 + *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Long(LongValue(*s as i64 + *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Short(ShortValue(*s + *o as i16))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Short(ShortValue(*s + *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Int(IntValue(*s as i32 + *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Long(LongValue(*s as i64 + *o))
 
            }
 
            (Value::Int(IntValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Int(IntValue(*s + *o as i32))
 
            }
 
            (Value::Int(IntValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Int(IntValue(*s + *o as i32))
 
            }
 
            (Value::Int(IntValue(s)), Value::Int(IntValue(o))) => Value::Int(IntValue(*s + *o)),
 
            (Value::Int(IntValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Long(LongValue(*s as i64 + *o))
 
            }
 
            (Value::Long(LongValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Long(LongValue(*s + *o as i64))
 
            }
 
            (Value::Long(LongValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Long(LongValue(*s + *o as i64))
 
            }
 
            (Value::Long(LongValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Long(LongValue(*s + *o as i64))
 
            }
 
            (Value::Long(LongValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Long(LongValue(*s + *o))
 
            }
 

	
 
            (Value::Message(MessageValue(s)), Value::Message(MessageValue(o))) => {
 
                let payload = if let [Some(s), Some(o)] = [s, o] {
 
                    let mut payload = s.clone();
 
                    payload.concatenate_with(o);
 
                    Some(payload)
 
                } else {
 
                    None
 
                };
 
                Value::Message(MessageValue(payload))
 
            }
 
            _ => unimplemented!(),
 
        }
 
    }
 
    fn minus(&self, other: &Value) -> Value {
 
        match (self, other) {
 
            (Value::Byte(ByteValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Byte(ByteValue(*s - *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Short(ShortValue(*s as i16 - *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Int(IntValue(*s as i32 - *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Long(LongValue(*s as i64 - *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Short(ShortValue(*s - *o as i16))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Short(ShortValue(*s - *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Int(IntValue(*s as i32 - *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Long(LongValue(*s as i64 - *o))
 
            }
 
            (Value::Int(IntValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Int(IntValue(*s - *o as i32))
 
            }
 
            (Value::Int(IntValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Int(IntValue(*s - *o as i32))
 
            }
 
            (Value::Int(IntValue(s)), Value::Int(IntValue(o))) => Value::Int(IntValue(*s - *o)),
 
            (Value::Int(IntValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Long(LongValue(*s as i64 - *o))
 
            }
 
            (Value::Long(LongValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Long(LongValue(*s - *o as i64))
 
            }
 
            (Value::Long(LongValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Long(LongValue(*s - *o as i64))
 
            }
 
            (Value::Long(LongValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Long(LongValue(*s - *o as i64))
 
            }
 
            (Value::Long(LongValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Long(LongValue(*s - *o))
 
            }
 
            _ => unimplemented!(),
 
        }
 
    }
 
    fn modulus(&self, other: &Value) -> Value {
 
        match (self, other) {
 
            (Value::Byte(ByteValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Byte(ByteValue(*s % *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Short(ShortValue(*s as i16 % *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Int(IntValue(*s as i32 % *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Long(LongValue(*s as i64 % *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Short(ShortValue(*s % *o as i16))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Short(ShortValue(*s % *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Int(IntValue(*s as i32 % *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Long(LongValue(*s as i64 % *o))
 
            }
 
            (Value::Int(IntValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Int(IntValue(*s % *o as i32))
 
            }
 
            (Value::Int(IntValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Int(IntValue(*s % *o as i32))
 
            }
 
            (Value::Int(IntValue(s)), Value::Int(IntValue(o))) => Value::Int(IntValue(*s % *o)),
 
            (Value::Int(IntValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Long(LongValue(*s as i64 % *o))
 
            }
 
            (Value::Long(LongValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Long(LongValue(*s % *o as i64))
 
            }
 
            (Value::Long(LongValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Long(LongValue(*s % *o as i64))
 
            }
 
            (Value::Long(LongValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Long(LongValue(*s % *o as i64))
 
            }
 
            (Value::Long(LongValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Long(LongValue(*s % *o))
 
            }
 
            _ => unimplemented!(),
 
        }
 
    }
 
    fn eq(&self, other: &Value) -> Value {
 
        match (self, other) {
 
            (Value::Byte(ByteValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Boolean(BooleanValue(*s == *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Boolean(BooleanValue(*s as i16 == *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Boolean(BooleanValue(*s as i32 == *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Boolean(BooleanValue(*s as i64 == *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Boolean(BooleanValue(*s == *o as i16))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Boolean(BooleanValue(*s == *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Boolean(BooleanValue(*s as i32 == *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Boolean(BooleanValue(*s as i64 == *o))
 
            }
 
            (Value::Int(IntValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Boolean(BooleanValue(*s == *o as i32))
 
            }
 
            (Value::Int(IntValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Boolean(BooleanValue(*s == *o as i32))
 
            }
 
            (Value::Int(IntValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Boolean(BooleanValue(*s == *o))
 
            }
 
            (Value::Int(IntValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Boolean(BooleanValue(*s as i64 == *o))
 
            }
 
            (Value::Long(LongValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Boolean(BooleanValue(*s == *o as i64))
 
            }
 
            (Value::Long(LongValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Boolean(BooleanValue(*s == *o as i64))
 
            }
 
            (Value::Long(LongValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Boolean(BooleanValue(*s == *o as i64))
 
            }
 
            (Value::Long(LongValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Boolean(BooleanValue(*s == *o))
 
            }
 
            (Value::Message(MessageValue(s)), Value::Message(MessageValue(o))) => {
 
                Value::Boolean(BooleanValue(*s == *o))
 
            }
 
            _ => unimplemented!(),
 
        }
 
    }
 
    fn neq(&self, other: &Value) -> Value {
 
        match (self, other) {
 
            (Value::Byte(ByteValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Boolean(BooleanValue(*s != *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Boolean(BooleanValue(*s as i16 != *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Boolean(BooleanValue(*s as i32 != *o))
 
            }
 
            (Value::Byte(ByteValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Boolean(BooleanValue(*s as i64 != *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Boolean(BooleanValue(*s != *o as i16))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Boolean(BooleanValue(*s != *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Boolean(BooleanValue(*s as i32 != *o))
 
            }
 
            (Value::Short(ShortValue(s)), Value::Long(LongValue(o))) => {
 
                Value::Boolean(BooleanValue(*s as i64 != *o))
 
            }
 
            (Value::Int(IntValue(s)), Value::Byte(ByteValue(o))) => {
 
                Value::Boolean(BooleanValue(*s != *o as i32))
 
            }
 
            (Value::Int(IntValue(s)), Value::Short(ShortValue(o))) => {
 
                Value::Boolean(BooleanValue(*s != *o as i32))
 
            }
 
            (Value::Int(IntValue(s)), Value::Int(IntValue(o))) => {
 
                Value::Boolean(BooleanValue(*s != *o))
 
            }
 
            (Value::Int(IntValue(s)), Value::Long(LongValue(o))) => {
 
@@ -1136,661 +1136,661 @@ impl Display for OutputArrayValue {
 

	
 
impl ValueImpl for OutputArrayValue {
 
    fn exact_type(&self) -> Type {
 
        Type::OUTPUT_ARRAY
 
    }
 
    fn is_type_compatible_hack(h: &Heap, t: &ParserType) -> bool {
 
        get_array_inner(t)
 
            .map(|v| OutputValue::is_type_compatible_hack(h, &h[v]))
 
            .unwrap_or(false)
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct MessageArrayValue(Vec<MessageValue>);
 

	
 
impl Display for MessageArrayValue {
 
    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
 
        write!(f, "{{")?;
 
        let mut first = true;
 
        for v in self.0.iter() {
 
            if !first {
 
                write!(f, ",")?;
 
            }
 
            write!(f, "{}", v)?;
 
            first = false;
 
        }
 
        write!(f, "}}")
 
    }
 
}
 

	
 
impl ValueImpl for MessageArrayValue {
 
    fn exact_type(&self) -> Type {
 
        Type::MESSAGE_ARRAY
 
    }
 
    fn is_type_compatible_hack(h: &Heap, t: &ParserType) -> bool {
 
        get_array_inner(t)
 
            .map(|v| MessageValue::is_type_compatible_hack(h, &h[v]))
 
            .unwrap_or(false)
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct BooleanArrayValue(Vec<BooleanValue>);
 

	
 
impl Display for BooleanArrayValue {
 
    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
 
        write!(f, "{{")?;
 
        let mut first = true;
 
        for v in self.0.iter() {
 
            if !first {
 
                write!(f, ",")?;
 
            }
 
            write!(f, "{}", v)?;
 
            first = false;
 
        }
 
        write!(f, "}}")
 
    }
 
}
 

	
 
impl ValueImpl for BooleanArrayValue {
 
    fn exact_type(&self) -> Type {
 
        Type::BOOLEAN_ARRAY
 
    }
 
    fn is_type_compatible_hack(h: &Heap, t: &ParserType) -> bool {
 
        get_array_inner(t)
 
            .map(|v| BooleanValue::is_type_compatible_hack(h, &h[v]))
 
            .unwrap_or(false)
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct ByteArrayValue(Vec<ByteValue>);
 

	
 
impl Display for ByteArrayValue {
 
    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
 
        write!(f, "{{")?;
 
        let mut first = true;
 
        for v in self.0.iter() {
 
            if !first {
 
                write!(f, ",")?;
 
            }
 
            write!(f, "{}", v)?;
 
            first = false;
 
        }
 
        write!(f, "}}")
 
    }
 
}
 

	
 
impl ValueImpl for ByteArrayValue {
 
    fn exact_type(&self) -> Type {
 
        Type::BYTE_ARRAY
 
    }
 
    fn is_type_compatible_hack(h: &Heap, t: &ParserType) -> bool {
 
        get_array_inner(t)
 
            .map(|v| ByteValue::is_type_compatible_hack(h, &h[v]))
 
            .unwrap_or(false)
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct ShortArrayValue(Vec<ShortValue>);
 

	
 
impl Display for ShortArrayValue {
 
    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
 
        write!(f, "{{")?;
 
        let mut first = true;
 
        for v in self.0.iter() {
 
            if !first {
 
                write!(f, ",")?;
 
            }
 
            write!(f, "{}", v)?;
 
            first = false;
 
        }
 
        write!(f, "}}")
 
    }
 
}
 

	
 
impl ValueImpl for ShortArrayValue {
 
    fn exact_type(&self) -> Type {
 
        Type::SHORT_ARRAY
 
    }
 
    fn is_type_compatible_hack(h: &Heap, t: &ParserType) -> bool {
 
        get_array_inner(t)
 
            .map(|v| ShortValue::is_type_compatible_hack(h, &h[v]))
 
            .unwrap_or(false)
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct IntArrayValue(Vec<IntValue>);
 

	
 
impl Display for IntArrayValue {
 
    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
 
        write!(f, "{{")?;
 
        let mut first = true;
 
        for v in self.0.iter() {
 
            if !first {
 
                write!(f, ",")?;
 
            }
 
            write!(f, "{}", v)?;
 
            first = false;
 
        }
 
        write!(f, "}}")
 
    }
 
}
 

	
 
impl ValueImpl for IntArrayValue {
 
    fn exact_type(&self) -> Type {
 
        Type::INT_ARRAY
 
    }
 
    fn is_type_compatible_hack(h: &Heap, t: &ParserType) -> bool {
 
        get_array_inner(t)
 
            .map(|v| IntValue::is_type_compatible_hack(h, &h[v]))
 
            .unwrap_or(false)
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct LongArrayValue(Vec<LongValue>);
 

	
 
impl Display for LongArrayValue {
 
    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
 
        write!(f, "{{")?;
 
        let mut first = true;
 
        for v in self.0.iter() {
 
            if !first {
 
                write!(f, ",")?;
 
            }
 
            write!(f, "{}", v)?;
 
            first = false;
 
        }
 
        write!(f, "}}")
 
    }
 
}
 

	
 
impl ValueImpl for LongArrayValue {
 
    fn exact_type(&self) -> Type {
 
        Type::LONG_ARRAY
 
    }
 
    fn is_type_compatible_hack(h: &Heap, t: &ParserType) -> bool {
 
        get_array_inner(t)
 
            .map(|v| LongValue::is_type_compatible_hack(h, &h[v]))
 
            .unwrap_or(false)
 
    }
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
struct Store {
 
    map: HashMap<VariableId, Value>,
 
}
 
impl Store {
 
    fn new() -> Self {
 
        Store { map: HashMap::new() }
 
    }
 
    fn initialize(&mut self, h: &Heap, var: VariableId, value: Value) {
 
        // Ensure value is compatible with type of variable
 
        let parser_type = match &h[var] {
 
            Variable::Local(v) => v.parser_type,
 
            Variable::Parameter(v) => v.parser_type,
 
        };
 
        assert!(value.is_type_compatible(h, &h[parser_type]));
 
        // Overwrite mapping
 
        self.map.insert(var, value.clone());
 
    }
 
    fn update(
 
        &mut self,
 
        h: &Heap,
 
        ctx: &mut EvalContext,
 
        lexpr: ExpressionId,
 
        value: Value,
 
    ) -> EvalResult {
 
        match &h[lexpr] {
 
            Expression::Variable(var) => {
 
                let var = var.declaration.unwrap();
 
                // Ensure value is compatible with type of variable
 
                let parser_type_id = match &h[var] {
 
                    Variable::Local(v) => v.parser_type,
 
                    Variable::Parameter(v) => v.parser_type
 
                };
 
                let parser_type = &h[parser_type_id];
 
                assert!(value.is_type_compatible(h, parser_type));
 
                // Overwrite mapping
 
                self.map.insert(var, value.clone());
 
                Ok(value)
 
            }
 
            Expression::Indexing(indexing) => {
 
                // Evaluate index expression, which must be some integral type
 
                let index = self.eval(h, ctx, indexing.index)?;
 
                // Mutable reference to the subject
 
                let subject;
 
                match &h[indexing.subject] {
 
                    Expression::Variable(var) => {
 
                        let var = var.declaration.unwrap();
 
                        subject = self.map.get_mut(&var).unwrap();
 
                    }
 
                    _ => unreachable!(),
 
                }
 
                match subject.set(&index, &value) {
 
                    Some(value) => Ok(value),
 
                    None => Err(EvalContinuation::Inconsistent),
 
                }
 
            }
 
            _ => unimplemented!("{:?}", h[lexpr]),
 
        }
 
    }
 
    fn get(&mut self, h: &Heap, ctx: &mut EvalContext, rexpr: ExpressionId) -> EvalResult {
 
        match &h[rexpr] {
 
            Expression::Variable(var) => {
 
                let var_id = var.declaration.unwrap();
 
                let value = self
 
                    .map
 
                    .get(&var_id)
 
                    .expect(&format!("Uninitialized variable {:?}", String::from_utf8_lossy(&var.identifier.value)));
 
                Ok(value.clone())
 
            }
 
            Expression::Indexing(indexing) => {
 
                // Evaluate index expression, which must be some integral type
 
                let index = self.eval(h, ctx, indexing.index)?;
 
                // Reference to subject
 
                let subject;
 
                match &h[indexing.subject] {
 
                    Expression::Variable(var) => {
 
                        let var = var.declaration.unwrap();
 
                        subject = self.map.get(&var).unwrap();
 
                    }
 
                    q => unreachable!("Reached {:?}", q),
 
                }
 
                match subject.get(&index) {
 
                    Some(value) => Ok(value),
 
                    None => Err(EvalContinuation::Inconsistent),
 
                }
 
            }
 
            Expression::Select(selecting) => {
 
                // Reference to subject
 
                let subject;
 
                match &h[selecting.subject] {
 
                    Expression::Variable(var) => {
 
                        let var = var.declaration.unwrap();
 
                        subject = self.map.get(&var).unwrap();
 
                    }
 
                    q => unreachable!("Reached {:?}", q),
 
                }
 
                match subject.length() {
 
                    Some(value) => Ok(value),
 
                    None => Err(EvalContinuation::Inconsistent),
 
                }
 
            }
 
            _ => unimplemented!("{:?}", h[rexpr]),
 
        }
 
    }
 
    fn eval(&mut self, h: &Heap, ctx: &mut EvalContext, expr: ExpressionId) -> EvalResult {
 
        match &h[expr] {
 
            Expression::Assignment(expr) => {
 
                let value = self.eval(h, ctx, expr.right)?;
 
                match expr.operation {
 
                    AssignmentOperator::Set => {
 
                        self.update(h, ctx, expr.left, value.clone())?;
 
                    }
 
                    AssignmentOperator::Added => {
 
                        let old = self.get(h, ctx, expr.left)?;
 
                        self.update(h, ctx, expr.left, old.plus(&value))?;
 
                    }
 
                    AssignmentOperator::Subtracted => {
 
                        let old = self.get(h, ctx, expr.left)?;
 
                        self.update(h, ctx, expr.left, old.minus(&value))?;
 
                    }
 
                    _ => unimplemented!("{:?}", expr),
 
                }
 
                Ok(value)
 
            }
 
            Expression::Conditional(expr) => {
 
                let test = self.eval(h, ctx, expr.test)?;
 
                if test.as_boolean().0 {
 
                    self.eval(h, ctx, expr.true_expression)
 
                } else {
 
                    self.eval(h, ctx, expr.false_expression)
 
                }
 
            }
 
            Expression::Binary(expr) => {
 
                let left = self.eval(h, ctx, expr.left)?;
 
                let right;
 
                match expr.operation {
 
                    BinaryOperator::LogicalAnd => {
 
                        if left.as_boolean().0 == false {
 
                            return Ok(left);
 
                        }
 
                        right = self.eval(h, ctx, expr.right)?;
 
                        right.as_boolean(); // panics if not a boolean
 
                        return Ok(right);
 
                    }
 
                    BinaryOperator::LogicalOr => {
 
                        if left.as_boolean().0 == true {
 
                            return Ok(left);
 
                        }
 
                        right = self.eval(h, ctx, expr.right)?;
 
                        right.as_boolean(); // panics if not a boolean
 
                        return Ok(right);
 
                    }
 
                    _ => {}
 
                }
 
                right = self.eval(h, ctx, expr.right)?;
 
                match expr.operation {
 
                    BinaryOperator::Equality => Ok(left.eq(&right)),
 
                    BinaryOperator::Inequality => Ok(left.neq(&right)),
 
                    BinaryOperator::LessThan => Ok(left.lt(&right)),
 
                    BinaryOperator::LessThanEqual => Ok(left.lte(&right)),
 
                    BinaryOperator::GreaterThan => Ok(left.gt(&right)),
 
                    BinaryOperator::GreaterThanEqual => Ok(left.gte(&right)),
 
                    BinaryOperator::Remainder => Ok(left.modulus(&right)),
 
                    BinaryOperator::Add => Ok(left.plus(&right)),
 
                    _ => unimplemented!("{:?}", expr.operation),
 
                }
 
            }
 
            Expression::Unary(expr) => {
 
                let mut value = self.eval(h, ctx, expr.expression)?;
 
                match expr.operation {
 
                    UnaryOperation::PostIncrement => {
 
                        self.update(h, ctx, expr.expression, value.plus(&ONE))?;
 
                    }
 
                    UnaryOperation::PreIncrement => {
 
                        value = value.plus(&ONE);
 
                        self.update(h, ctx, expr.expression, value.clone())?;
 
                    }
 
                    UnaryOperation::PostDecrement => {
 
                        self.update(h, ctx, expr.expression, value.minus(&ONE))?;
 
                    }
 
                    UnaryOperation::PreDecrement => {
 
                        value = value.minus(&ONE);
 
                        self.update(h, ctx, expr.expression, value.clone())?;
 
                    }
 
                    _ => unimplemented!(),
 
                }
 
                Ok(value)
 
            }
 
            Expression::Indexing(expr) => self.get(h, ctx, expr.this.upcast()),
 
            Expression::Slicing(_expr) => unimplemented!(),
 
            Expression::Select(expr) => self.get(h, ctx, expr.this.upcast()),
 
            Expression::Array(expr) => {
 
                let mut elements = Vec::new();
 
                for &elem in expr.elements.iter() {
 
                    elements.push(self.eval(h, ctx, elem)?);
 
                }
 
                todo!()
 
            }
 
            Expression::Constant(expr) => Ok(Value::from_constant(&expr.value)),
 
            Expression::Literal(expr) => Ok(Value::from_constant(&expr.value)),
 
            Expression::Call(expr) => match &expr.method {
 
                Method::Get => {
 
                    assert_eq!(1, expr.arguments.len());
 
                    let value = self.eval(h, ctx, expr.arguments[0])?;
 
                    match ctx.get(value.clone()) {
 
                        None => Err(EvalContinuation::BlockGet(value)),
 
                        Some(result) => Ok(result),
 
                    }
 
                }
 
                Method::Put => {
 
                    assert_eq!(2, expr.arguments.len());
 
                    let port_value = self.eval(h, ctx, expr.arguments[0])?;
 
                    let msg_value = self.eval(h, ctx, expr.arguments[1])?;
 
                    if ctx.did_put(port_value.clone()) {
 
                        // Return bogus, replacing this at some point anyway
 
                        Ok(Value::Message(MessageValue(None)))
 
                    } else {
 
                        Err(EvalContinuation::Put(port_value, msg_value))
 
                    }
 
                }
 
                Method::Fires => {
 
                    assert_eq!(1, expr.arguments.len());
 
                    let value = self.eval(h, ctx, expr.arguments[0])?;
 
                    match ctx.fires(value.clone()) {
 
                        None => Err(EvalContinuation::BlockFires(value)),
 
                        Some(result) => Ok(result),
 
                    }
 
                }
 
                Method::Create => {
 
                    assert_eq!(1, expr.arguments.len());
 
                    let length = self.eval(h, ctx, expr.arguments[0])?;
 
                    Ok(Value::create_message(length))
 
                }
 
                Method::Symbolic(_symbol) => unimplemented!(),
 
            },
 
            Expression::Variable(expr) => self.get(h, ctx, expr.this.upcast()),
 
        }
 
    }
 
}
 

	
 
type EvalResult = Result<Value, EvalContinuation>;
 
pub enum EvalContinuation {
 
    Stepping,
 
    Inconsistent,
 
    Terminal,
 
    SyncBlockStart,
 
    SyncBlockEnd,
 
    NewComponent(DefinitionId, Vec<Value>),
 
    BlockFires(Value),
 
    BlockGet(Value),
 
    Put(Value, Value),
 
}
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub(crate) struct Prompt {
 
    definition: DefinitionId,
 
    store: Store,
 
    position: Option<StatementId>,
 
}
 

	
 
impl Prompt {
 
    pub fn new(h: &Heap, def: DefinitionId, args: &Vec<Value>) -> Self {
 
        let mut prompt =
 
            Prompt { definition: def, store: Store::new(), position: Some((&h[def]).body()) };
 
        prompt.set_arguments(h, args);
 
        prompt
 
    }
 
    fn set_arguments(&mut self, h: &Heap, args: &Vec<Value>) {
 
        let def = &h[self.definition];
 
        let params = def.parameters();
 
        assert_eq!(params.len(), args.len());
 
        for (param, value) in params.iter().zip(args.iter()) {
 
            let hparam = &h[*param];
 
            let parser_type = &h[hparam.parser_type];
 
            assert!(value.is_type_compatible(h, parser_type));
 
            self.store.initialize(h, param.upcast(), value.clone());
 
        }
 
    }
 
    pub fn step(&mut self, h: &Heap, ctx: &mut EvalContext) -> EvalResult {
 
        if self.position.is_none() {
 
            return Err(EvalContinuation::Terminal);
 
        }
 

	
 
        let stmt = &h[self.position.unwrap()];
 
        match stmt {
 
            Statement::Block(stmt) => {
 
                // Continue to first statement
 
                self.position = Some(stmt.first());
 
                Err(EvalContinuation::Stepping)
 
            }
 
            Statement::Local(stmt) => {
 
                match stmt {
 
                    LocalStatement::Memory(stmt) => {
 
                        // Update store
 
                        self.store.initialize(h, stmt.variable.upcast(), Value::Unassigned);
 
                    }
 
                    LocalStatement::Channel(stmt) => {
 
                        let [from, to] = ctx.new_channel();
 
                        // Store the values in the declared variables
 
                        self.store.initialize(h, stmt.from.upcast(), from);
 
                        self.store.initialize(h, stmt.to.upcast(), to);
 
                    }
 
                }
 
                // Continue to next statement
 
                self.position = stmt.next();
 
                Err(EvalContinuation::Stepping)
 
            }
 
            Statement::Skip(stmt) => {
 
                // Continue to next statement
 
                self.position = stmt.next;
 
                Err(EvalContinuation::Stepping)
 
            }
 
            Statement::Labeled(stmt) => {
 
                // Continue to next statement
 
                self.position = Some(stmt.body);
 
                Err(EvalContinuation::Stepping)
 
            }
 
            Statement::If(stmt) => {
 
                // Evaluate test
 
                let value = self.store.eval(h, ctx, stmt.test)?;
 
                // Continue with either branch
 
                if value.as_boolean().0 {
 
                    self.position = Some(stmt.true_body);
 
                } else {
 
                    self.position = Some(stmt.false_body);
 
                }
 
                Err(EvalContinuation::Stepping)
 
            }
 
            Statement::EndIf(stmt) => {
 
                // Continue to next statement
 
                self.position = stmt.next;
 
                Err(EvalContinuation::Stepping)
 
            }
 
            Statement::While(stmt) => {
 
                // Evaluate test
 
                let value = self.store.eval(h, ctx, stmt.test)?;
 
                // Either continue with body, or go to next
 
                if value.as_boolean().0 {
 
                    self.position = Some(stmt.body);
 
                } else {
 
                    self.position = stmt.end_while.map(|x| x.upcast());
 
                }
 
                Err(EvalContinuation::Stepping)
 
            }
 
            Statement::EndWhile(stmt) => {
 
                // Continue to next statement
 
                self.position = stmt.next;
 
                Err(EvalContinuation::Stepping)
 
            }
 
            Statement::Synchronous(stmt) => {
 
                // Continue to next statement, and signal upward
 
                self.position = Some(stmt.body);
 
                Err(EvalContinuation::SyncBlockStart)
 
            }
 
            Statement::EndSynchronous(stmt) => {
 
                // Continue to next statement, and signal upward
 
                self.position = stmt.next;
 
                Err(EvalContinuation::SyncBlockEnd)
 
            }
 
            Statement::Break(stmt) => {
 
                // Continue to end of while
 
                self.position = stmt.target.map(EndWhileStatementId::upcast);
 
                Err(EvalContinuation::Stepping)
 
            }
 
            Statement::Continue(stmt) => {
 
                // Continue to beginning of while
 
                self.position = stmt.target.map(WhileStatementId::upcast);
 
                Err(EvalContinuation::Stepping)
 
            }
 
            Statement::Assert(stmt) => {
 
                // Evaluate expression
 
                let value = self.store.eval(h, ctx, stmt.expression)?;
 
                if value.as_boolean().0 {
 
                    // Continue to next statement
 
                    self.position = stmt.next;
 
                    Err(EvalContinuation::Stepping)
 
                } else {
 
                    // Assertion failed: inconsistent
 
                    Err(EvalContinuation::Inconsistent)
 
                }
 
            }
 
            Statement::Return(stmt) => {
 
                // Evaluate expression
 
                let value = self.store.eval(h, ctx, stmt.expression)?;
 
                // Done with evaluation
 
                Ok(value)
 
            }
 
            Statement::Goto(stmt) => {
 
                // Continue to target
 
                self.position = stmt.target.map(|x| x.upcast());
 
                Err(EvalContinuation::Stepping)
 
            }
 
            Statement::New(stmt) => {
 
                let expr = &h[stmt.expression];
 
                let mut args = Vec::new();
 
                for &arg in expr.arguments.iter() {
 
                    let value = self.store.eval(h, ctx, arg)?;
 
                    args.push(value);
 
                }
 
                self.position = stmt.next;
 
                match &expr.method {
 
                    Method::Symbolic(symbolic) => {
 
                         Err(EvalContinuation::NewComponent(symbolic.definition.unwrap(), args))
 
                    },
 
                    _ => unreachable!("not a symbolic call expression")
 
                }
 
            }
 
            Statement::Expression(stmt) => {
 
                // Evaluate expression
 
                let _value = self.store.eval(h, ctx, stmt.expression)?;
 
                // Continue to next statement
 
                self.position = stmt.next;
 
                Err(EvalContinuation::Stepping)
 
            }
 
        }
 
    }
 
    // fn compute_function(_h: &Heap, _fun: FunctionId, _args: &Vec<Value>) -> Option<Value> {
 
    // let mut prompt = Self::new(h, fun.upcast(), args);
 
    // let mut context = EvalContext::None;
 
    // loop {
 
    //     let result = prompt.step(h, &mut context);
 
    //     match result {
 
    //         Ok(val) => return Some(val),
 
    //         Err(cont) => match cont {
 
    //             EvalContinuation::Stepping => continue,
 
    //             EvalContinuation::Inconsistent => return None,
 
    //             // Functions never terminate without returning
 
    //             EvalContinuation::Terminal => unreachable!(),
 
    //             // Functions never encounter any blocking behavior
 
    //             EvalContinuation::SyncBlockStart => unreachable!(),
 
    //             EvalContinuation::SyncBlockEnd => unreachable!(),
 
    //             EvalContinuation::NewComponent(_, _) => unreachable!(),
 
    //             EvalContinuation::BlockFires(val) => unreachable!(),
 
    //             EvalContinuation::BlockGet(val) => unreachable!(),
 
    //             EvalContinuation::Put(port, msg) => unreachable!(),
 
    //         },
 
    //     }
 
    // }
 
    // }
 
}
 

	
 
// #[cfg(test)]
 
// mod tests {
 
//     extern crate test_generator;
 

	
 
//     use std::fs::File;
 
//     use std::io::Read;
 
//     use std::path::Path;
 
//     use test_generator::test_resources;
 

	
 
//     use super::*;
 

	
 
//     #[test_resources("testdata/eval/positive/*.pdl")]
 
//     fn batch1(resource: &str) {
 
//         let path = Path::new(resource);
 
//         let expect = path.with_extension("txt");
 
//         let mut heap = Heap::new();
 
//         let mut source = InputSource::from_file(&path).unwrap();
 
//         let mut parser = Parser::new(&mut source);
 
//         let pd = parser.parse(&mut heap).unwrap();
 
//         let def = heap[pd].get_definition_ident(&heap, b"test").unwrap();
 
//         let fun = heap[def].as_function().this;
 
//         let args = Vec::new();
 
//         let result = Prompt::compute_function(&heap, fun, &args).unwrap();
 
//         let valstr: String = format!("{}", result);
 
//         println!("{}", valstr);
 

	
 
//         let mut cev: Vec<u8> = Vec::new();
 
//         let mut f = File::open(expect).unwrap();
 
//         f.read_to_end(&mut cev).unwrap();
 
//         let lavstr = String::from_utf8_lossy(&cev);
 
//         println!("{}", lavstr);
 

	
 
//         assert_eq!(valstr, lavstr);
 
//     }
 
// }
src/protocol/inputsource.rs
Show inline comments
 
use std::fmt;
 
use std::fs::File;
 
use std::io;
 
use std::path::Path;
 

	
 
use backtrace::Backtrace;
 

	
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub struct InputSource {
 
    pub(crate) filename: String,
 
    pub(crate) input: Vec<u8>,
 
    line: usize,
 
    column: usize,
 
    offset: usize,
 
}
 

	
 
static STD_LIB_PDL: &'static [u8] = b"
 
primitive forward(in<msg> i, out<msg> o) {
 
    while(true) synchronous put(o, get(i));
 
}
 
primitive sync(in<msg> i, out<msg> o) {
 
    while(true) synchronous if(fires(i)) put(o, get(i));
 
}
 
primitive alternator(in<msg> i, out<msg> l, out<msg> r) {
 
    while(true) {
 
        synchronous if(fires(i)) put(l, get(i));
 
        synchronous if(fires(i)) put(r, get(i));
 
    }
 
}
 
primitive replicator(in<msg> i, out<msg> l, out<msg> r) {
 
    while(true) synchronous {
 
        if(fires(i)) {
 
            msg m = get(i);
 
            put(l, m);
 
            put(r, m);
 
        }
 
    }
 
}
 
primitive merger(in<msg> l, in<msg> r, out<msg> o) {
 
    while(true) synchronous {
 
        if(fires(l))      put(o, get(l));
 
        else if(fires(r)) put(o, get(r));
 
    }
 
}
 
";
 

	
 
impl InputSource {
 
    // Constructors
 
    pub fn new<R: io::Read, S: ToString>(filename: S, reader: &mut R) -> io::Result<InputSource> {
 
        let mut vec = Vec::new();
 
        reader.read_to_end(&mut vec)?;
 
        vec.extend(STD_LIB_PDL.to_vec());
 
        Ok(InputSource {
 
            filename: filename.to_string(),
 
            input: vec,
 
            line: 1,
 
            column: 1,
 
            offset: 0,
 
        })
 
    }
 
    // Constructor helpers
 
    pub fn from_file(path: &Path) -> io::Result<InputSource> {
 
        let filename = path.file_name();
 
        match filename {
 
            Some(filename) => {
 
                let mut f = File::open(path)?;
 
                InputSource::new(filename.to_string_lossy(), &mut f)
 
            }
 
            None => Err(io::Error::new(io::ErrorKind::NotFound, "Invalid path")),
 
        }
 
    }
 
    pub fn from_string(string: &str) -> io::Result<InputSource> {
 
        let buffer = Box::new(string);
 
        let mut bytes = buffer.as_bytes();
 
        InputSource::new(String::new(), &mut bytes)
 
    }
 
    pub fn from_buffer(buffer: &[u8]) -> io::Result<InputSource> {
 
        InputSource::new(String::new(), &mut Box::new(buffer))
 
    }
 
    // Internal methods
 
    pub fn pos(&self) -> InputPosition {
 
        InputPosition { line: self.line, column: self.column, offset: self.offset }
 
    }
 
    pub fn seek(&mut self, pos: InputPosition) {
 
        debug_assert!(pos.offset < self.input.len());
 
        self.line = pos.line;
 
        self.column = pos.column;
 
        self.offset = pos.offset;
 
    }
 
    // pub fn error<S: ToString>(&self, message: S) -> ParseError {
 
    //     self.pos().parse_error(message)
 
    // }
 
    pub fn is_eof(&self) -> bool {
 
        self.next() == None
 
    }
 

	
 
    pub fn next(&self) -> Option<u8> {
 
        if self.offset < self.input.len() {
 
            Some(self.input[self.offset])
 
        } else {
 
            None
 
        }
 
    }
 

	
 
    pub fn lookahead(&self, pos: usize) -> Option<u8> {
 
        let offset_pos = self.offset + pos;
 
        if offset_pos < self.input.len() {
 
            Some(self.input[offset_pos])
 
        } else {
 
            None
 
        }
 
    }
 

	
 
    pub fn has(&self, to_compare: &[u8]) -> bool {
 
        if self.offset + to_compare.len() <= self.input.len() {
 
            for idx in 0..to_compare.len() {
 
                if to_compare[idx] != self.input[self.offset + idx] {
 
                    return false;
 
                }
 
            }
 

	
 
            true
 
        } else {
 
            false
 
        }
 
    }
 

	
 
    pub fn consume(&mut self) {
 
        match self.next() {
 
            Some(x) if x == b'\r' && self.lookahead(1) != Some(b'\n') || x == b'\n' => {
 
                self.line += 1;
 
                self.offset += 1;
 
                self.column = 1;
 
            }
 
            Some(_) => {
 
                self.offset += 1;
 
                self.column += 1;
 
            }
 
            None => {}
 
        }
 
    }
 
}
 

	
 
impl fmt::Display for InputSource {
 
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 
        self.pos().fmt(f)
 
    }
 
}
 

	
 
#[derive(Debug, Clone, Copy, serde::Serialize, serde::Deserialize)]
 
pub struct InputPosition {
 
    line: usize,
 
    column: usize,
 
    offset: usize,
 
}
 

	
 
impl InputPosition {
 
    fn context<'a>(&self, source: &'a InputSource) -> &'a [u8] {
 
        let start = self.offset - (self.column - 1);
 
        let mut end = self.offset;
 
        while end < source.input.len() {
 
            let cur = (*source.input)[end];
 
            if cur == b'\n' || cur == b'\r' {
 
                break;
 
            }
 
            end += 1;
 
        }
 
        &source.input[start..end]
 
    }
 
    // fn parse_error<S: ToString>(&self, message: S) -> ParseError {
 
    //     ParseError { position: *self, message: message.to_string(), backtrace: Backtrace::new() }
 
    // }
 
    fn eval_error<S: ToString>(&self, message: S) -> EvalError {
 
        EvalError { position: *self, message: message.to_string(), backtrace: Backtrace::new() }
 
    }
 

	
 
    pub(crate) fn col(&self) -> usize { self.column }
 
}
 

	
 
impl Default for InputPosition {
 
    fn default() -> Self {
 
        Self{ line: 1, column: 1, offset: 0 }
 
    }
 
}
 

	
 
impl fmt::Display for InputPosition {
 
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 
        write!(f, "{}:{}", self.line, self.column)
 
    }
 
}
 

	
 
pub trait SyntaxElement {
 
    fn position(&self) -> InputPosition;
 
    fn error<S: ToString>(&self, message: S) -> EvalError {
 
        self.position().eval_error(message)
 
    }
 
}
 

	
 
#[derive(Debug)]
 
pub enum ParseErrorType {
 
    Info,
 
    Error
 
}
 

	
 
#[derive(Debug)]
 
pub struct ParseErrorStatement {
 
    error_type: ParseErrorType,
 
    position: InputPosition,
 
    filename: String,
 
    context: String,
 
    message: String,
 
    pub(crate) error_type: ParseErrorType,
 
    pub(crate) position: InputPosition,
 
    pub(crate) filename: String,
 
    pub(crate) context: String,
 
    pub(crate) message: String,
 
}
 

	
 
impl ParseErrorStatement {
 
    fn from_source(error_type: ParseErrorType, source: &InputSource, position: InputPosition, msg: &str) -> Self {
 
        // Seek line start and end
 
        let line_start = position.offset - (position.column - 1);
 
        let mut line_end = position.offset;
 
        while line_end < source.input.len() && source.input[line_end] != b'\n' {
 
            line_end += 1;
 
        }
 

	
 
        // Compensate for '\r\n'
 
        if line_end > line_start && source.input[line_end - 1] == b'\r' {
 
            line_end -= 1;
 
        }
 

	
 
        Self{
 
            error_type,
 
            position,
 
            filename: source.filename.clone(),
 
            context: String::from_utf8_lossy(&source.input[line_start..line_end]).to_string(),
 
            message: msg.to_string()
 
        }
 
    }
 
}
 

	
 
impl fmt::Display for ParseErrorStatement {
 
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 
        // Write message
 
        match self.error_type {
 
            ParseErrorType::Info => write!(f, " INFO: ")?,
 
            ParseErrorType::Error => write!(f, "ERROR: ")?,
 
        }
 
        writeln!(f, "{}", &self.message)?;
 

	
 
        // Write originating file/line/column
 
        if self.filename.is_empty() {
 
            writeln!(f, " +- at {}:{}", self.position.line, self.position.column)?;
 
        } else {
 
            writeln!(f, " +- at {}:{}:{}", self.filename, self.position.line, self.position.column)?;
 
        }
 

	
 
        // Write source context
 
        writeln!(f, " | ")?;
 
        writeln!(f, " | {}", self.context)?;
 

	
 
        // Write underline indicating where the error ocurred
 
        debug_assert!(self.position.column <= self.context.chars().count());
 
        let mut arrow = String::with_capacity(self.context.len() + 3);
 
        arrow.push_str(" | ");
 
        let mut char_col = 1;
 
        for char in self.context.chars() {
 
            if char_col == self.position.column { break; }
 
            if char == '\t' {
 
                arrow.push('\t');
 
            } else {
 
                arrow.push(' ');
 
            }
 

	
 
            char_col += 1;
 
        }
 
        arrow.push('^');
 
        writeln!(f, "{}", arrow)?;
 

	
 
        Ok(())
 
    }
 
}
 

	
 
#[derive(Debug)]
 
pub struct ParseError2 {
 
    statements: Vec<ParseErrorStatement>
 
    pub(crate) statements: Vec<ParseErrorStatement>
 
}
 

	
 
impl fmt::Display for ParseError2 {
 
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 
        if self.statements.is_empty() {
 
            return Ok(())
 
        }
 

	
 
        self.statements[0].fmt(f)?;
 
        for statement in self.statements.iter().skip(1) {
 
            writeln!(f)?;
 
            statement.fmt(f)?;
 
        }
 

	
 
        Ok(())
 
    }
 
}
 

	
 
impl ParseError2 {
 
    pub fn empty() -> Self {
 
        Self{ statements: Vec::new() }
 
    }
 

	
 
    pub fn new_error(source: &InputSource, position: InputPosition, msg: &str) -> Self {
 
        Self{ statements: vec!(ParseErrorStatement::from_source(ParseErrorType::Error, source, position, msg))}
 
    }
 

	
 
    pub fn with_prefixed(mut self, error_type: ParseErrorType, source: &InputSource, position: InputPosition, msg: &str) -> Self {
 
        self.statements.insert(0, ParseErrorStatement::from_source(error_type, source, position, msg));
 
        self
 
    }
 

	
 
    pub fn with_postfixed(mut self, error_type: ParseErrorType, source: &InputSource, position: InputPosition, msg: &str) -> Self {
 
        self.statements.push(ParseErrorStatement::from_source(error_type, source, position, msg));
 
        self
 
    }
 

	
 
    pub fn with_postfixed_info(self, source: &InputSource, position: InputPosition, msg: &str) -> Self {
 
        self.with_postfixed(ParseErrorType::Info, source, position, msg)
 
    }
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub struct EvalError {
 
    position: InputPosition,
 
    message: String,
 
    backtrace: Backtrace,
 
}
 

	
 
impl EvalError {
 
    pub fn new<S: ToString>(position: InputPosition, message: S) -> EvalError {
 
        EvalError { position, message: message.to_string(), backtrace: Backtrace::new() }
 
    }
 
    // Diagnostic methods
 
    pub fn write<A: io::Write>(&self, source: &InputSource, writer: &mut A) -> io::Result<()> {
 
        if !source.filename.is_empty() {
 
            writeln!(
 
                writer,
 
                "Evaluation error at {}:{}: {}",
 
                source.filename, self.position, self.message
 
            )?;
 
        } else {
 
            writeln!(writer, "Evaluation error at {}: {}", self.position, self.message)?;
 
        }
 
        let line = self.position.context(source);
 
        writeln!(writer, "{}", String::from_utf8_lossy(line))?;
 
        let mut arrow: Vec<u8> = Vec::new();
 
        for pos in 1..self.position.column {
 
            let c = line[pos - 1];
 
            if c == b'\t' {
 
                arrow.push(b'\t')
 
            } else {
 
                arrow.push(b' ')
 
            }
 
        }
 
        arrow.push(b'^');
 
        writeln!(writer, "{}", String::from_utf8_lossy(&arrow))
 
    }
 
    pub fn print(&self, source: &InputSource) {
 
        self.write(source, &mut std::io::stdout()).unwrap()
 
    }
 
    pub fn display<'a>(&'a self, source: &'a InputSource) -> DisplayEvalError<'a> {
 
        DisplayEvalError::new(self, source)
 
    }
 
}
 

	
 
impl From<EvalError> for io::Error {
 
    fn from(_: EvalError) -> io::Error {
 
        io::Error::new(io::ErrorKind::InvalidInput, "eval error")
 
    }
 
}
 

	
 
#[derive(Clone, Copy)]
 
pub struct DisplayEvalError<'a> {
 
    error: &'a EvalError,
 
    source: &'a InputSource,
 
}
 

	
 
impl DisplayEvalError<'_> {
 
    fn new<'a>(error: &'a EvalError, source: &'a InputSource) -> DisplayEvalError<'a> {
 
        DisplayEvalError { error, source }
 
    }
 
}
 

	
 
impl fmt::Display for DisplayEvalError<'_> {
 
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 
        let mut vec: Vec<u8> = Vec::new();
 
        match self.error.write(self.source, &mut vec) {
 
            Err(_) => {
 
                return fmt::Result::Err(fmt::Error);
 
            }
 
            Ok(_) => {}
 
        }
 
        write!(f, "{}", String::from_utf8_lossy(&vec))
 
    }
 
}
 

	
 
// #[cfg(test)]
 
// mod tests {
 
//     use super::*;
 

	
 
//     #[test]
 
//     fn test_from_string() {
 
//         let mut is = InputSource::from_string("#version 100\n").unwrap();
 
//         assert!(is.input.len() == 13);
 
//         assert!(is.line == 1);
 
//         assert!(is.column == 1);
 
//         assert!(is.offset == 0);
 
//         let ps = is.pos();
 
//         assert!(ps.line == 1);
 
//         assert!(ps.column == 1);
 
//         assert!(ps.offset == 0);
 
//         assert!(is.next() == Some(b'#'));
 
//         is.consume();
 
//         assert!(is.next() == Some(b'v'));
 
//         assert!(is.lookahead(1) == Some(b'e'));
 
//         is.consume();
 
//         assert!(is.next() == Some(b'e'));
 
//         is.consume();
 
//         assert!(is.next() == Some(b'r'));
 
//         is.consume();
 
//         assert!(is.next() == Some(b's'));
 
//         is.consume();
 
//         assert!(is.next() == Some(b'i'));
 
//         is.consume();
 
//         {
 
//             let ps = is.pos();
 
//             assert_eq!(b"#version 100", ps.context(&is));
 
//             let er = is.error("hello world!");
 
//             let mut vec: Vec<u8> = Vec::new();
 
//             er.write(&is, &mut vec).unwrap();
 
//             assert_eq!(
 
//                 "Parse error at 1:7: hello world!\n#version 100\n      ^\n",
 
//                 String::from_utf8_lossy(&vec)
 
//             );
 
//         }
 
//         assert!(is.next() == Some(b'o'));
 
//         is.consume();
 
//         assert!(is.next() == Some(b'n'));
 
//         is.consume();
 
//         assert!(is.input.len() == 13);
 
//         assert!(is.line == 1);
 
//         assert!(is.column == 9);
 
//         assert!(is.offset == 8);
 
//         assert!(is.next() == Some(b' '));
 
//         is.consume();
 
//         assert!(is.next() == Some(b'1'));
 
//         is.consume();
 
//         assert!(is.next() == Some(b'0'));
 
//         is.consume();
 
//         assert!(is.next() == Some(b'0'));
 
//         is.consume();
 
//         assert!(is.input.len() == 13);
 
//         assert!(is.line == 1);
 
//         assert!(is.column == 13);
 
//         assert!(is.offset == 12);
 
//         assert!(is.next() == Some(b'\n'));
 
//         is.consume();
 
//         assert!(is.input.len() == 13);
 
//         assert!(is.line == 2);
 
//         assert!(is.column == 1);
 
//         assert!(is.offset == 13);
 
//         {
 
//             let ps = is.pos();
 
//             assert_eq!(b"", ps.context(&is));
 
//         }
 
//         assert!(is.next() == None);
 
//         is.consume();
 
//         assert!(is.next() == None);
 
//     }
 

	
 
//     #[test]
 
//     fn test_split() {
 
//         let mut is = InputSource::from_string("#version 100\n").unwrap();
 
//         let backup = is.clone();
 
//         assert!(is.next() == Some(b'#'));
 
//         is.consume();
 
//         assert!(is.next() == Some(b'v'));
 
//         is.consume();
 
//         assert!(is.next() == Some(b'e'));
 
//         is.consume();
 
//         is = backup;
 
//         assert!(is.next() == Some(b'#'));
 
//         is.consume();
 
//         assert!(is.next() == Some(b'v'));
 
//         is.consume();
 
//         assert!(is.next() == Some(b'e'));
 
//         is.consume();
 
//     }
 
// }
src/protocol/lexer.rs
Show inline comments
 
use crate::protocol::ast::*;
 
use crate::protocol::inputsource::*;
 

	
 
const MAX_LEVEL: usize = 128;
 
const MAX_NAMESPACES: u8 = 8; // only three levels are supported at the moment
 

	
 
fn is_vchar(x: Option<u8>) -> bool {
 
    if let Some(c) = x {
 
        c >= 0x21 && c <= 0x7E
 
    } else {
 
        false
 
    }
 
}
 

	
 
fn is_wsp(x: Option<u8>) -> bool {
 
    if let Some(c) = x {
 
        c == b' ' || c == b'\t'
 
    } else {
 
        false
 
    }
 
}
 

	
 
fn is_ident_start(x: Option<u8>) -> bool {
 
    if let Some(c) = x {
 
        c >= b'A' && c <= b'Z' || c >= b'a' && c <= b'z'
 
    } else {
 
        false
 
    }
 
}
 

	
 
fn is_ident_rest(x: Option<u8>) -> bool {
 
    if let Some(c) = x {
 
        c >= b'A' && c <= b'Z' || c >= b'a' && c <= b'z' || c >= b'0' && c <= b'9' || c == b'_'
 
    } else {
 
        false
 
    }
 
}
 

	
 
fn is_constant(x: Option<u8>) -> bool {
 
    if let Some(c) = x {
 
        c >= b'0' && c <= b'9' || c == b'\''
 
    } else {
 
        false
 
    }
 
}
 

	
 
fn is_integer_start(x: Option<u8>) -> bool {
 
    if let Some(c) = x {
 
        c >= b'0' && c <= b'9'
 
    } else {
 
        false
 
    }
 
}
 

	
 
fn is_integer_rest(x: Option<u8>) -> bool {
 
    if let Some(c) = x {
 
        c >= b'0' && c <= b'9'
 
            || c >= b'a' && c <= b'f'
 
            || c >= b'A' && c <= b'F'
 
            || c == b'x'
 
            || c == b'o'
 
    } else {
 
        false
 
    }
 
}
 

	
 
fn lowercase(x: u8) -> u8 {
 
    if x >= b'A' && x <= b'Z' {
 
        x - b'A' + b'a'
 
    } else {
 
        x
 
    }
 
}
 

	
 
pub struct Lexer<'a> {
 
    source: &'a mut InputSource,
 
    level: usize,
 
}
 

	
 
impl Lexer<'_> {
 
    pub fn new(source: &mut InputSource) -> Lexer {
 
        Lexer { source, level: 0 }
 
    }
 
    fn error_at_pos(&self, msg: &str) -> ParseError2 {
 
        ParseError2::new_error(self.source, self.source.pos(), msg)
 
    }
 
    fn consume_line(&mut self) -> Result<Vec<u8>, ParseError2> {
 
        let mut result: Vec<u8> = Vec::new();
 
        let mut next = self.source.next();
 
        while next.is_some() && next != Some(b'\n') && next != Some(b'\r') {
 
            if !(is_vchar(next) || is_wsp(next)) {
 
                return Err(self.error_at_pos("Expected visible character or whitespace"));
 
            }
 
            result.push(next.unwrap());
 
            self.source.consume();
 
            next = self.source.next();
 
        }
 
        if next.is_some() {
 
            self.source.consume();
 
        }
 
        if next == Some(b'\r') && self.source.next() == Some(b'\n') {
 
            self.source.consume();
 
        }
 
        Ok(result)
 
    }
 
    fn consume_whitespace(&mut self, expected: bool) -> Result<(), ParseError2> {
 
        let mut found = false;
 
        let mut next = self.source.next();
 
        while next.is_some() {
 
            if next == Some(b' ')
 
                || next == Some(b'\t')
 
                || next == Some(b'\r')
 
                || next == Some(b'\n')
 
            {
 
                self.source.consume();
 
                next = self.source.next();
 
                found = true;
 
                continue;
 
            }
 
            if next == Some(b'/') {
 
                next = self.source.lookahead(1);
 
                if next == Some(b'/') {
 
                    self.source.consume(); // slash
 
                    self.source.consume(); // slash
 
                    self.consume_line()?;
 
                    next = self.source.next();
 
                    found = true;
 
                    continue;
 
                }
 
                if next == Some(b'*') {
 
                    self.source.consume(); // slash
 
                    self.source.consume(); // star
 
                    next = self.source.next();
 
                    while next.is_some() {
 
                        if next == Some(b'*') {
 
                            next = self.source.lookahead(1);
 
                            if next == Some(b'/') {
 
                                self.source.consume(); // star
 
                                self.source.consume(); // slash
 
                                break;
 
                            }
 
                        }
 
                        self.source.consume();
 
                        next = self.source.next();
 
                    }
 
                    next = self.source.next();
 
                    found = true;
 
                    continue;
 
                }
 
            }
 
            break;
 
        }
 
        if expected && !found {
 
            Err(self.error_at_pos("Expected whitespace"))
 
        } else {
 
            Ok(())
 
        }
 
    }
 
    fn consume_any_chars(&mut self) {
 
        if !is_ident_start(self.source.next()) { return }
 
        self.source.consume();
 
        while is_ident_rest(self.source.next()) {
 
            self.source.consume()
 
        }
 
    }
 
    fn has_keyword(&self, keyword: &[u8]) -> bool {
 
        if !self.source.has(keyword) {
 
            return false;
 
        }
 

	
 
        // Word boundary
 
        if let Some(next) = self.source.lookahead(keyword.len()) {
 
            !(next >= b'A' && next <= b'Z' || next >= b'a' && next <= b'z')
 
        } else {
 
            true
 
        }
 
    }
 
    fn consume_keyword(&mut self, keyword: &[u8]) -> Result<(), ParseError2> {
 
        let len = keyword.len();
 
        for i in 0..len {
 
            let expected = Some(lowercase(keyword[i]));
 
            let next = self.source.next();
 
            if next != expected {
 
                return Err(self.error_at_pos(&format!("Expected keyword '{}'", String::from_utf8_lossy(keyword))));
 
            }
 
            self.source.consume();
 
        }
 
        if let Some(next) = self.source.next() {
 
            if next >= b'A' && next <= b'Z' || next >= b'a' && next <= b'z' || next >= b'0' && next <= b'9' {
 
                return Err(self.error_at_pos(&format!("Expected word boundary after '{}'", String::from_utf8_lossy(keyword))));
 
            }
 
        }
 
        Ok(())
 
    }
 
    fn has_string(&self, string: &[u8]) -> bool {
 
        self.source.has(string)
 
    }
 
    fn consume_string(&mut self, string: &[u8]) -> Result<(), ParseError2> {
 
        let len = string.len();
 
        for i in 0..len {
 
            let expected = Some(string[i]);
 
            let next = self.source.next();
 
            if next != expected {
 
                return Err(self.error_at_pos(&format!("Expected {}", String::from_utf8_lossy(string))));
 
            }
 
            self.source.consume();
 
        }
 
        Ok(())
 
    }
 
    /// Generic comma-separated consumer. If opening delimiter is not found then
 
    /// `Ok(None)` will be returned. Otherwise will consume the comma separated
 
    /// values, allowing a trailing comma. If no comma is found and the closing
 
    /// delimiter is not found, then a parse error with `expected_end_msg` is
 
    /// returned.
 
    fn consume_comma_separated<T, F>(
 
        &mut self, h: &mut Heap, open: u8, close: u8, expected_end_msg: &str, func: F
 
    ) -> Result<Option<Vec<T>>, ParseError2>
 
        where F: Fn(&mut Lexer, &mut Heap) -> Result<T, ParseError2>
 
    {
 
        if Some(open) != self.source.next() {
 
            return Ok(None)
 
        }
 

	
 
        self.source.consume();
 
        self.consume_whitespace(false)?;
 
        let mut elements = Vec::new();
 
        let mut had_comma = true;
 

	
 
        loop {
 
            if Some(close) == self.source.next() {
 
                self.source.consume();
 
                break;
 
            } else if !had_comma {
 
                return Err(ParseError2::new_error(
 
                    &self.source, self.source.pos(), expected_end_msg
 
                ));
 
            }
 

	
 
            elements.push(func(self, h)?);
 
            self.consume_whitespace(false)?;
 

	
 
            had_comma = self.source.next() == Some(b',');
 
            if had_comma {
 
                self.source.consume();
 
                self.consume_whitespace(false)?;
 
            }
 
        }
 

	
 
        Ok(Some(elements))
 
    }
 
    /// Essentially the same as `consume_comma_separated`, but will not allocate
 
    /// memory. Will return `true` and leave the input position at the end of
 
    /// the comma-separated list if well formed. Otherwise returns `false` and
 
    /// leaves the input position at a "random" position.
 
    fn consume_comma_separated_spilled_without_pos_recovery<F: Fn(&mut Lexer) -> bool>(
 
        &mut self, open: u8, close: u8, func: F
 
    ) -> bool {
 
        if Some(open) != self.source.next() {
 
            return true;
 
        }
 

	
 
        self.source.consume();
 
        if self.consume_whitespace(false).is_err() { return false };
 
        let mut had_comma = true;
 
        loop {
 
            if Some(close) == self.source.next() {
 
                self.source.consume();
 
                return true;
 
            } else if !had_comma {
 
                return false;
 
            }
 

	
 
            if !func(self) { return false; }
 
            if self.consume_whitespace(false).is_err() { return false };
 

	
 
            had_comma = self.source.next() == Some(b',');
 
            if had_comma {
 
                self.source.consume();
 
                if self.consume_whitespace(false).is_err() { return false; }
 
            }
 
        }
 

	
 
        true
 
    }
 
    fn consume_ident(&mut self) -> Result<Vec<u8>, ParseError2> {
 
        if !self.has_identifier() {
 
            return Err(self.error_at_pos("Expected identifier"));
 
        }
 
        let mut result = Vec::new();
 
        let mut next = self.source.next();
 
        result.push(next.unwrap());
 
        self.source.consume();
 
        next = self.source.next();
 
        while is_ident_rest(next) {
 
            result.push(next.unwrap());
 
            self.source.consume();
 
            next = self.source.next();
 
        }
 
        Ok(result)
 
    }
 
    fn has_integer(&mut self) -> bool {
 
        is_integer_start(self.source.next())
 
    }
 
    fn consume_integer(&mut self) -> Result<i64, ParseError2> {
 
        let position = self.source.pos();
 
        let mut data = Vec::new();
 
        let mut next = self.source.next();
 
        while is_integer_rest(next) {
 
            data.push(next.unwrap());
 
            self.source.consume();
 
            next = self.source.next();
 
        }
 

	
 
        let data_len = data.len();
 
        debug_assert_ne!(data_len, 0);
 
        if data_len == 1 {
 
            debug_assert!(data[0] >= b'0' && data[0] <= b'9');
 
            return Ok((data[0] - b'0') as i64);
 
        } else {
 
            // TODO: Fix, u64 should be supported as well
 
            let parsed = if data[1] == b'b' {
 
                let data = String::from_utf8_lossy(&data[2..]);
 
                i64::from_str_radix(&data, 2)
 
            } else if data[1] == b'o' {
 
                let data = String::from_utf8_lossy(&data[2..]);
 
                i64::from_str_radix(&data, 8)
 
            } else if data[1] == b'x' {
 
                let data = String::from_utf8_lossy(&data[2..]);
 
                i64::from_str_radix(&data, 16)
 
            } else {
 
                // Assume decimal
 
                let data = String::from_utf8_lossy(&data);
 
                i64::from_str_radix(&data, 10)
 
            };
 

	
 
            if let Err(_err) = parsed {
 
                return Err(ParseError2::new_error(&self.source, position, "Invalid integer constant"));
 
            }
 

	
 
            Ok(parsed.unwrap())
 
        }
 
    }
 

	
 
    // Statement keywords
 
    // TODO: Clean up these functions
 
    fn has_statement_keyword(&self) -> bool {
 
        self.has_keyword(b"channel")
 
            || self.has_keyword(b"skip")
 
            || self.has_keyword(b"if")
 
            || self.has_keyword(b"while")
 
            || self.has_keyword(b"break")
 
            || self.has_keyword(b"continue")
 
            || self.has_keyword(b"synchronous")
 
            || self.has_keyword(b"return")
 
            || self.has_keyword(b"assert")
 
            || self.has_keyword(b"goto")
 
            || self.has_keyword(b"new")
 
    }
 
    fn has_type_keyword(&self) -> bool {
 
        self.has_keyword(b"in")
 
            || self.has_keyword(b"out")
 
            || self.has_keyword(b"msg")
 
            || self.has_keyword(b"boolean")
 
            || self.has_keyword(b"byte")
 
            || self.has_keyword(b"short")
 
            || self.has_keyword(b"int")
 
            || self.has_keyword(b"long")
 
            || self.has_keyword(b"auto")
 
    }
 
    fn has_builtin_keyword(&self) -> bool {
 
        self.has_keyword(b"get")
 
            || self.has_keyword(b"fires")
 
            || self.has_keyword(b"create")
 
            || self.has_keyword(b"length")
 
    }
 
    fn has_reserved(&self) -> bool {
 
        self.has_statement_keyword()
 
            || self.has_type_keyword()
 
            || self.has_builtin_keyword()
 
            || self.has_keyword(b"let")
 
            || self.has_keyword(b"struct")
 
            || self.has_keyword(b"enum")
 
            || self.has_keyword(b"true")
 
            || self.has_keyword(b"false")
 
            || self.has_keyword(b"null")
 
    }
 

	
 
    // Identifiers
 

	
 
    fn has_identifier(&self) -> bool {
 
        if self.has_statement_keyword() || self.has_type_keyword() || self.has_builtin_keyword() {
 
            return false;
 
        }
 
        let next = self.source.next();
 
        is_ident_start(next)
 
    }
 
    fn consume_identifier(&mut self) -> Result<Identifier, ParseError2> {
 
        if self.has_statement_keyword() || self.has_type_keyword() || self.has_builtin_keyword() {
 
            return Err(self.error_at_pos("Expected identifier"));
 
        }
 
        let position = self.source.pos();
 
        let value = self.consume_ident()?;
 
        Ok(Identifier{ position, value })
 
    }
 
    fn consume_identifier_spilled(&mut self) -> Result<(), ParseError2> {
 
        if self.has_statement_keyword() || self.has_type_keyword() || self.has_builtin_keyword() {
 
            return Err(self.error_at_pos("Expected identifier"));
 
        }
 
        self.consume_ident()?;
 
        Ok(())
 
    }
 
    fn has_namespaced_identifier(&self) -> bool { 
 
        self.has_identifier() 
 
    }
 
    fn consume_namespaced_identifier(&mut self) -> Result<NamespacedIdentifier, ParseError2> {
 
        if self.has_reserved() {
 
            return Err(self.error_at_pos("Encountered reserved keyword"));
 
        }
 

	
 
        let position = self.source.pos();
 
        let mut ns_ident = self.consume_ident()?;
 
        let mut num_namespaces = 1;
 
        while self.has_string(b"::") {
 
            self.consume_string(b"::");
 
            if num_namespaces >= MAX_NAMESPACES {
 
                return Err(self.error_at_pos("Too many namespaces in identifier"));
 
            }
 
            let new_ident = self.consume_ident()?;
 
            ns_ident.extend(b"::");
 
            ns_ident.extend(new_ident);
 
            num_namespaces += 1;
 
        }
 

	
 
        Ok(NamespacedIdentifier{
 
            position,
 
            value: ns_ident,
 
            num_namespaces,
 
        })
 
    }
 
    fn consume_namespaced_identifier_spilled(&mut self) -> Result<(), ParseError2> {
 
        // TODO: @performance
 
        if self.has_reserved() {
 
            return Err(self.error_at_pos("Encountered reserved keyword"));
 
        }
 

	
 
        self.consume_ident()?;
 
        while self.has_string(b"::") {
 
            self.consume_string(b"::")?;
 
            self.consume_ident()?;
 
        }
 

	
 
        Ok(())
 
    }
 

	
 
    // Types and type annotations
 

	
 
    /// Consumes a type definition. When called the input position should be at
 
    /// the type specification. When done the input position will be at the end
 
    /// of the type specifications (hence may be at whitespace).
 
    fn consume_type2(&mut self, h: &mut Heap, allow_inference: bool) -> Result<ParserTypeId, ParseError2> {
 
        // Small helper function to convert in/out polymorphic arguments. Not
 
        // pretty, but return boolean is true if the error is due to inference
 
        // not being allowed
 
        let reduce_port_poly_args = |
 
            heap: &mut Heap,
 
            port_pos: &InputPosition,
 
            args: Vec<ParserTypeId>,
 
        | -> Result<ParserTypeId, bool> {
 
            match args.len() {
 
                0 => if allow_inference {  
 
                    Ok(heap.alloc_parser_type(|this| ParserType{
 
                        this,
 
                        pos: port_pos.clone(),
 
                        variant: ParserTypeVariant::Inferred
 
                    }))
 
                } else {
 
                    Err(true)
 
                },
 
                1 => Ok(args[0]),
 
                _ => Err(false)
 
            }
 
        };
 

	
 
        // Consume the type
 
        let pos = self.source.pos();
 
        let parser_type_variant = if self.has_keyword(b"msg") {
 
            self.consume_keyword(b"msg")?;
 
            ParserTypeVariant::Message
 
        } else if self.has_keyword(b"boolean") {
 
            self.consume_keyword(b"boolean")?;
 
            ParserTypeVariant::Bool
 
        } else if self.has_keyword(b"byte") {
 
            self.consume_keyword(b"byte")?;
 
            ParserTypeVariant::Byte
 
        } else if self.has_keyword(b"short") {
 
            self.consume_keyword(b"short")?;
 
            ParserTypeVariant::Short
 
        } else if self.has_keyword(b"int") {
 
            self.consume_keyword(b"int")?;
 
            ParserTypeVariant::Int
 
        } else if self.has_keyword(b"long") {
 
            self.consume_keyword(b"long")?;
 
            ParserTypeVariant::Long
 
        } else if self.has_keyword(b"str") {
 
            self.consume_keyword(b"str")?;
 
            ParserTypeVariant::String
 
        } else if self.has_keyword(b"auto") {
 
            if !allow_inference {
 
                return Err(ParseError2::new_error(
 
                        &self.source, pos,
 
                        "Type inference is not allowed here"
 
                ));
 
            }
 

	
 
            self.consume_keyword(b"auto")?;
 
            ParserTypeVariant::Inferred
 
        } else if self.has_keyword(b"in") {
 
            // TODO: @cleanup: not particularly neat to have this special case
 
            //  where we enforce polyargs in the parser-phase
 
            // TODO: @hack, temporarily allow inferred port values
 
            self.consume_keyword(b"in")?;
 
            let poly_args = self.consume_polymorphic_args(h, allow_inference)?;
 
            let poly_arg = reduce_port_poly_args(h, &pos, poly_args)
 
                .map_err(|infer_error|  {
 
                    let msg = if infer_error {
 
                        "Type inference is not allowed here"
 
                    } else {
 
                        "Type 'in' only allows for 1 polymorphic argument"
 
                    };
 
                    ParseError2::new_error(&self.source, pos, msg)
 
                })?;
 
            ParserTypeVariant::Input(poly_arg)
 
        } else if self.has_keyword(b"out") {
 
            // TODO: @hack, temporarily allow inferred port values
 
            self.consume_keyword(b"out")?;
 
            let poly_args = self.consume_polymorphic_args(h, allow_inference)?;
 
            let poly_arg = reduce_port_poly_args(h, &pos, poly_args)
 
                .map_err(|infer_error| {
 
                    let msg = if infer_error {
 
                        "Type inference is not allowed here"
 
                    } else {
 
                        "Type 'out' only allows for 1 polymorphic argument, but {} were specified"
 
                    };
 
                    ParseError2::new_error(&self.source, pos, msg)
 
                })?;
 
            ParserTypeVariant::Output(poly_arg)
 
        } else {
 
            // Must be a symbolic type
 
            let identifier = self.consume_namespaced_identifier()?;
 
            let poly_args = self.consume_polymorphic_args(h, allow_inference)?;
 
            ParserTypeVariant::Symbolic(SymbolicParserType{identifier, poly_args, variant: None})
 
        };
 

	
 
        // If the type was a basic type (not supporting polymorphic type
 
        // arguments), then we make sure the user did not specify any of them.
 
        let mut backup_pos = self.source.pos();
 
        if !parser_type_variant.supports_polymorphic_args() {
 
            self.consume_whitespace(false)?;
 
            if let Some(b'<') = self.source.next() {
 
                return Err(ParseError2::new_error(
 
                    &self.source, self.source.pos(),
 
                    "This type does not allow polymorphic arguments"
 
                ));
 
            }
 

	
 
            self.source.seek(backup_pos);
 
        }
 

	
 
        let mut parser_type_id = h.alloc_parser_type(|this| ParserType{
 
            this, pos, variant: parser_type_variant
 
        });
 

	
 
        // If we're dealing with arrays, then we need to wrap the currently
 
        // parsed type in array types
 
        self.consume_whitespace(false)?;
 
        while let Some(b'[') = self.source.next() {
 
            let pos = self.source.pos();
 
            self.source.consume();
 
            self.consume_whitespace(false)?;
 
            if let Some(b']') = self.source.next() {
 
                // Type is wrapped in an array
 
                self.source.consume();
 
                parser_type_id = h.alloc_parser_type(|this| ParserType{
 
                    this, pos, variant: ParserTypeVariant::Array(parser_type_id)
 
                });
 
                backup_pos = self.source.pos();
 

	
 
                // In case we're dealing with another array
 
                self.consume_whitespace(false)?;
 
            } else {
 
                return Err(ParseError2::new_error(
 
                    &self.source, pos,
 
                    "Expected a closing ']'"
 
                ));
 
            }
 
        }
 

	
 
        self.source.seek(backup_pos);
 
        Ok(parser_type_id)
 
    }
 

	
 
    /// Attempts to consume a type without returning it. If it doesn't encounter
 
    /// a well-formed type, then the input position is left at a "random"
 
    /// position.
 
    fn maybe_consume_type_spilled_without_pos_recovery(&mut self) -> bool {
 
        // Consume type identifier
 
        if self.has_type_keyword() {
 
            self.consume_any_chars();
 
        } else {
 
            let ident = self.consume_namespaced_identifier();
 
            if ident.is_err() { return false; }
 
        }
 

	
 
        // Consume any polymorphic arguments that follow the type identifier
 
        let mut backup_pos = self.source.pos();
 
        if self.consume_whitespace(false).is_err() { return false; }
 
        if !self.maybe_consume_poly_args_spilled_without_pos_recovery() { return false; }
 
        // Consume any array specifiers. Make sure we always leave the input
 
        // position at the end of the last array specifier if we do find a
 
        // valid type
 

	
 
        if self.consume_whitespace(false).is_err() { return false; }
 
        while let Some(b'[') = self.source.next() {
 
            self.source.consume();
 
            if self.consume_whitespace(false).is_err() { return false; }
 
            if self.source.next() != Some(b']') { return false; }
 
            self.source.consume();
 
            backup_pos = self.source.pos();
 
            if self.consume_whitespace(false).is_err() { return false; }
 
        }
 

	
 
        self.source.seek(backup_pos);
 
        return true;
 
    }
 

	
 
    fn maybe_consume_type_spilled(&mut self) -> bool {
 
        let backup_pos = self.source.pos();
 
        if !self.maybe_consume_type_spilled_without_pos_recovery() {
 
            self.source.seek(backup_pos);
 
            return false;
 
        }
 

	
 
        return true;
 
    }
 

	
 
    /// Attempts to consume polymorphic arguments without returning them. If it
 
    /// doesn't encounter well-formed polymorphic arguments, then the input
 
    /// position is left at a "random" position.
 
    fn maybe_consume_poly_args_spilled_without_pos_recovery(&mut self) -> bool {
 
        if let Some(b'<') = self.source.next() {
 
            self.source.consume();
 
            if self.consume_whitespace(false).is_err() { return false; }
 
            loop {
 
                if !self.maybe_consume_type_spilled_without_pos_recovery() { return false; }
 
                if self.consume_whitespace(false).is_err() { return false; }
 
                let has_comma = self.source.next() == Some(b',');
 
                if has_comma {
 
                    self.source.consume();
 
                    if self.consume_whitespace(false).is_err() { return false; }
 
                }
 
                if let Some(b'>') = self.source.next() {
 
                    self.source.consume();
 
                    break;
 
                } else if !has_comma {
 
                    return false;
 
                }
 
            }
 
        }
 

	
 
        return true;
 
        self.consume_comma_separated_spilled_without_pos_recovery(
 
            b'<', b'>', |lexer| {
 
                lexer.maybe_consume_type_spilled_without_pos_recovery()
 
            })
 
    }
 

	
 
    /// Consumes polymorphic arguments and its delimiters if specified. The
 
    /// input position may be at whitespace. If polyargs are present then the
 
    /// whitespace and the args are consumed and the input position will be
 
    /// placed after the polyarg list. If polyargs are not present then the
 
    /// input position will remain unmodified and an empty vector will be
 
    /// Consumes polymorphic arguments and its delimiters if specified. If
 
    /// polyargs are present then the args are consumed and the input position
 
    /// will be placed after the polyarg list. If polyargs are not present then
 
    /// the input position will remain unmodified and an empty vector will be
 
    /// returned.
 
    ///
 
    /// Polymorphic arguments represent the specification of the parametric
 
    /// types of a polymorphic type: they specify the value of the polymorphic
 
    /// type's polymorphic variables.
 
    fn consume_polymorphic_args(&mut self, h: &mut Heap, allow_inference: bool) -> Result<Vec<ParserTypeId>, ParseError2> {
 
        let backup_pos = self.source.pos();
 
        self.consume_whitespace(false)?;
 
        if let Some(b'<') = self.source.next() {
 
            // Has polymorphic args, at least one type must be specified
 
            self.source.consume();
 
            self.consume_whitespace(false)?;
 
            let mut poly_args = Vec::new();
 

	
 
            loop {
 
                // TODO: @cleanup, remove the no_more_types var
 
                poly_args.push(self.consume_type2(h, allow_inference)?);
 
                self.consume_whitespace(false)?;
 

	
 
                let has_comma = self.source.next() == Some(b',');
 
                if has_comma {
 
                    // We might not actually be getting more types when the
 
                    // comma is at the end of the line, and we get a closing
 
                    // angular bracket on the next line.
 
                    self.source.consume();
 
                    self.consume_whitespace(false)?;
 
                }
 

	
 
                if let Some(b'>') = self.source.next() {
 
                    self.source.consume();
 
                    break;
 
                } else if !has_comma {
 
                    return Err(ParseError2::new_error(
 
                        &self.source, self.source.pos(),
 
                        "Expected the end of the polymorphic argument list"
 
                    ))
 
                }
 
            }
 

	
 
            Ok(poly_args)
 
        } else {
 
            // No polymorphic args
 
        match self.consume_comma_separated(
 
            h, b'<', b'>', "Expected the end of the polymorphic argument list",
 
            |lexer, heap| lexer.consume_type2(heap, allow_inference)
 
        )? {
 
            Some(poly_args) => Ok(poly_args),
 
            None => {
 
                self.source.seek(backup_pos);
 
            Ok(vec!())
 
                Ok(vec![])
 
            }
 
        }
 
    }
 

	
 
    /// Consumes polymorphic variables. These are identifiers that are used
 
    /// within polymorphic types. The input position may be at whitespace. If
 
    /// polymorphic variables are present then the whitespace, wrapping
 
    /// delimiters and the polymorphic variables are consumed. Otherwise the
 
    /// input position will stay where it is. If no polymorphic variables are
 
    /// present then an empty vector will be returned.
 
    fn consume_polymorphic_vars(&mut self) -> Result<Vec<Identifier>, ParseError2> {
 
    fn consume_polymorphic_vars(&mut self, h: &mut Heap) -> Result<Vec<Identifier>, ParseError2> {
 
        let backup_pos = self.source.pos();
 
        if let Some(b'<') = self.source.next() {
 
            // Found the opening delimiter, we want at least one polyvar
 
            self.source.consume();
 
            self.consume_whitespace(false)?;
 
            let mut poly_vars = Vec::new();
 

	
 
            loop {
 
                poly_vars.push(self.consume_identifier()?);
 
                self.consume_whitespace(false)?;
 

	
 
                let has_comma = self.source.next() == Some(b',');
 
                if has_comma {
 
                    // We may get another variable
 
                    self.source.consume();
 
                    self.consume_whitespace(false)?;
 
                }
 

	
 
                if let Some(b'>') = self.source.next() {
 
                    self.source.consume();
 
                    break;
 
                } else if !has_comma {
 
                    return Err(ParseError2::new_error(
 
                        &self.source, self.source.pos(),
 
                        "Expected the end of the polymorphic variable list"
 
                    ))
 
                }
 
            }
 

	
 
            Ok(poly_vars)
 
        } else {
 
            // No polymorphic args
 
        match self.consume_comma_separated(
 
            h, b'<', b'>', "Expected the end of the polymorphic variable list",
 
            |lexer, heap| lexer.consume_identifier()
 
        )? {
 
            Some(poly_vars) => Ok(poly_vars),
 
            None => {
 
                self.source.seek(backup_pos);
 
                Ok(vec!())
 
            }
 
        }
 
    }
 

	
 
    // Parameters
 

	
 
    fn consume_parameter(&mut self, h: &mut Heap) -> Result<ParameterId, ParseError2> {
 
        let parser_type = self.consume_type2(h, false)?;
 
        self.consume_whitespace(true)?;
 
        let position = self.source.pos();
 
        let identifier = self.consume_identifier()?;
 
        let id =
 
            h.alloc_parameter(|this| Parameter { this, position, parser_type, identifier });
 
        Ok(id)
 
    }
 
    fn consume_parameters(
 
        &mut self,
 
        h: &mut Heap,
 
        params: &mut Vec<ParameterId>,
 
    ) -> Result<(), ParseError2> {
 
        self.consume_string(b"(")?;
 
        self.consume_whitespace(false)?;
 
        if !self.has_string(b")") {
 
            while self.source.next().is_some() {
 
                params.push(self.consume_parameter(h)?);
 
                self.consume_whitespace(false)?;
 
                if self.has_string(b")") {
 
                    break;
 
                }
 
                self.consume_string(b",")?;
 
                self.consume_whitespace(false)?;
 
    fn consume_parameters(&mut self, h: &mut Heap) -> Result<Vec<ParameterId>, ParseError2> {
 
        match self.consume_comma_separated(
 
            h, b'(', b')', "Expected the end of the parameter list",
 
            |lexer, heap| lexer.consume_parameter(heap)
 
        )? {
 
            Some(params) => Ok(params),
 
            None => {
 
                Err(ParseError2::new_error(
 
                    &self.source, self.source.pos(),
 
                    "Expected a parameter list"
 
                ))
 
            }
 
        }
 
        self.consume_string(b")")?;
 

	
 
        Ok(())
 
    }
 

	
 
    // ====================
 
    // Expressions
 
    // ====================
 

	
 
    fn consume_paren_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        self.consume_string(b"(")?;
 
        self.consume_whitespace(false)?;
 
        let result = self.consume_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        self.consume_string(b")")?;
 
        Ok(result)
 
    }
 
    fn consume_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        if self.level >= MAX_LEVEL {
 
            return Err(self.error_at_pos("Too deeply nested expression"));
 
        }
 
        self.level += 1;
 
        let result = self.consume_assignment_expression(h);
 
        self.level -= 1;
 
        result
 
    }
 
    fn consume_assignment_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let result = self.consume_conditional_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        if self.has_assignment_operator() {
 
            let position = self.source.pos();
 
            let left = result;
 
            let operation = self.consume_assignment_operator()?;
 
            self.consume_whitespace(false)?;
 
            let right = self.consume_expression(h)?;
 
            Ok(h.alloc_assignment_expression(|this| AssignmentExpression {
 
                this,
 
                position,
 
                left,
 
                operation,
 
                right,
 
                parent: ExpressionParent::None,
 
                concrete_type: ConcreteType::default(),
 
            })
 
            .upcast())
 
        } else {
 
            Ok(result)
 
        }
 
    }
 
    fn has_assignment_operator(&self) -> bool {
 
        self.has_string(b"=")
 
            || self.has_string(b"*=")
 
            || self.has_string(b"/=")
 
            || self.has_string(b"%=")
 
            || self.has_string(b"+=")
 
            || self.has_string(b"-=")
 
            || self.has_string(b"<<=")
 
            || self.has_string(b">>=")
 
            || self.has_string(b"&=")
 
            || self.has_string(b"^=")
 
            || self.has_string(b"|=")
 
    }
 
    fn consume_assignment_operator(&mut self) -> Result<AssignmentOperator, ParseError2> {
 
        if self.has_string(b"=") {
 
            self.consume_string(b"=")?;
 
            Ok(AssignmentOperator::Set)
 
        } else if self.has_string(b"*=") {
 
            self.consume_string(b"*=")?;
 
            Ok(AssignmentOperator::Multiplied)
 
        } else if self.has_string(b"/=") {
 
            self.consume_string(b"/=")?;
 
            Ok(AssignmentOperator::Divided)
 
        } else if self.has_string(b"%=") {
 
            self.consume_string(b"%=")?;
 
            Ok(AssignmentOperator::Remained)
 
        } else if self.has_string(b"+=") {
 
            self.consume_string(b"+=")?;
 
            Ok(AssignmentOperator::Added)
 
        } else if self.has_string(b"-=") {
 
            self.consume_string(b"-=")?;
 
            Ok(AssignmentOperator::Subtracted)
 
        } else if self.has_string(b"<<=") {
 
            self.consume_string(b"<<=")?;
 
            Ok(AssignmentOperator::ShiftedLeft)
 
        } else if self.has_string(b">>=") {
 
            self.consume_string(b">>=")?;
 
            Ok(AssignmentOperator::ShiftedRight)
 
        } else if self.has_string(b"&=") {
 
            self.consume_string(b"&=")?;
 
            Ok(AssignmentOperator::BitwiseAnded)
 
        } else if self.has_string(b"^=") {
 
            self.consume_string(b"^=")?;
 
            Ok(AssignmentOperator::BitwiseXored)
 
        } else if self.has_string(b"|=") {
 
            self.consume_string(b"|=")?;
 
            Ok(AssignmentOperator::BitwiseOred)
 
        } else {
 
            Err(self.error_at_pos("Expected assignment operator"))
 
        }
 
    }
 
    fn consume_conditional_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let result = self.consume_concat_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        if self.has_string(b"?") {
 
            let position = self.source.pos();
 
            let test = result;
 
            self.consume_string(b"?")?;
 
            self.consume_whitespace(false)?;
 
            let true_expression = self.consume_expression(h)?;
 
            self.consume_whitespace(false)?;
 
            self.consume_string(b":")?;
 
            self.consume_whitespace(false)?;
 
            let false_expression = self.consume_expression(h)?;
 
            Ok(h.alloc_conditional_expression(|this| ConditionalExpression {
 
                this,
 
                position,
 
                test,
 
                true_expression,
 
                false_expression,
 
                parent: ExpressionParent::None,
 
                concrete_type: ConcreteType::default(),
 
            })
 
            .upcast())
 
        } else {
 
            Ok(result)
 
        }
 
    }
 
    fn consume_concat_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let mut result = self.consume_lor_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        while self.has_string(b"@") {
 
            let position = self.source.pos();
 
            let left = result;
 
            self.consume_string(b"@")?;
 
            let operation = BinaryOperator::Concatenate;
 
            self.consume_whitespace(false)?;
 
            let right = self.consume_lor_expression(h)?;
 
            self.consume_whitespace(false)?;
 
            result = h
 
                .alloc_binary_expression(|this| BinaryExpression {
 
                    this,
 
                    position,
 
                    left,
 
                    operation,
 
                    right,
 
                    parent: ExpressionParent::None,
 
                    concrete_type: ConcreteType::default(),
 
                })
 
                .upcast();
 
        }
 
        Ok(result)
 
    }
 
    fn consume_lor_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let mut result = self.consume_land_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        while self.has_string(b"||") {
 
            let position = self.source.pos();
 
            let left = result;
 
            self.consume_string(b"||")?;
 
            let operation = BinaryOperator::LogicalOr;
 
            self.consume_whitespace(false)?;
 
            let right = self.consume_land_expression(h)?;
 
            self.consume_whitespace(false)?;
 
            result = h
 
                .alloc_binary_expression(|this| BinaryExpression {
 
                    this,
 
                    position,
 
                    left,
 
                    operation,
 
                    right,
 
                    parent: ExpressionParent::None,
 
                    concrete_type: ConcreteType::default(),
 
                })
 
                .upcast();
 
        }
 
        Ok(result)
 
    }
 
    fn consume_land_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let mut result = self.consume_bor_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        while self.has_string(b"&&") {
 
            let position = self.source.pos();
 
            let left = result;
 
            self.consume_string(b"&&")?;
 
            let operation = BinaryOperator::LogicalAnd;
 
            self.consume_whitespace(false)?;
 
            let right = self.consume_bor_expression(h)?;
 
            self.consume_whitespace(false)?;
 
            result = h
 
                .alloc_binary_expression(|this| BinaryExpression {
 
                    this,
 
                    position,
 
                    left,
 
                    operation,
 
                    right,
 
                    parent: ExpressionParent::None,
 
                    concrete_type: ConcreteType::default(),
 
                })
 
                .upcast();
 
        }
 
        Ok(result)
 
    }
 
    fn consume_bor_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let mut result = self.consume_xor_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        while self.has_string(b"|") && !self.has_string(b"||") && !self.has_string(b"|=") {
 
            let position = self.source.pos();
 
            let left = result;
 
            self.consume_string(b"|")?;
 
            let operation = BinaryOperator::BitwiseOr;
 
            self.consume_whitespace(false)?;
 
            let right = self.consume_xor_expression(h)?;
 
            self.consume_whitespace(false)?;
 
            result = h
 
                .alloc_binary_expression(|this| BinaryExpression {
 
                    this,
 
                    position,
 
                    left,
 
                    operation,
 
                    right,
 
                    parent: ExpressionParent::None,
 
                    concrete_type: ConcreteType::default(),
 
                })
 
                .upcast();
 
        }
 
        Ok(result)
 
    }
 
    fn consume_xor_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let mut result = self.consume_band_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        while self.has_string(b"^") && !self.has_string(b"^=") {
 
            let position = self.source.pos();
 
            let left = result;
 
            self.consume_string(b"^")?;
 
            let operation = BinaryOperator::BitwiseXor;
 
            self.consume_whitespace(false)?;
 
            let right = self.consume_band_expression(h)?;
 
            self.consume_whitespace(false)?;
 
            result = h
 
                .alloc_binary_expression(|this| BinaryExpression {
 
                    this,
 
                    position,
 
                    left,
 
                    operation,
 
                    right,
 
                    parent: ExpressionParent::None,
 
                    concrete_type: ConcreteType::default(),
 
                })
 
                .upcast();
 
        }
 
        Ok(result)
 
    }
 
    fn consume_band_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let mut result = self.consume_eq_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        while self.has_string(b"&") && !self.has_string(b"&&") && !self.has_string(b"&=") {
 
            let position = self.source.pos();
 
            let left = result;
 
            self.consume_string(b"&")?;
 
            let operation = BinaryOperator::BitwiseAnd;
 
            self.consume_whitespace(false)?;
 
            let right = self.consume_eq_expression(h)?;
 
            self.consume_whitespace(false)?;
 
            result = h
 
                .alloc_binary_expression(|this| BinaryExpression {
 
                    this,
 
                    position,
 
                    left,
 
                    operation,
 
                    right,
 
                    parent: ExpressionParent::None,
 
                    concrete_type: ConcreteType::default(),
 
                })
 
                .upcast();
 
        }
 
        Ok(result)
 
    }
 
    fn consume_eq_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let mut result = self.consume_rel_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        while self.has_string(b"==") || self.has_string(b"!=") {
 
            let position = self.source.pos();
 
            let left = result;
 
            let operation;
 
            if self.has_string(b"==") {
 
                self.consume_string(b"==")?;
 
                operation = BinaryOperator::Equality;
 
            } else {
 
                self.consume_string(b"!=")?;
 
                operation = BinaryOperator::Inequality;
 
            }
 
            self.consume_whitespace(false)?;
 
            let right = self.consume_rel_expression(h)?;
 
            self.consume_whitespace(false)?;
 
            result = h
 
                .alloc_binary_expression(|this| BinaryExpression {
 
                    this,
 
                    position,
 
                    left,
 
                    operation,
 
                    right,
 
                    parent: ExpressionParent::None,
 
                    concrete_type: ConcreteType::default(),
 
                })
 
                .upcast();
 
        }
 
        Ok(result)
 
    }
 
    fn consume_rel_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let mut result = self.consume_shift_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        while self.has_string(b"<=")
 
            || self.has_string(b">=")
 
            || self.has_string(b"<") && !self.has_string(b"<<=")
 
            || self.has_string(b">") && !self.has_string(b">>=")
 
        {
 
            let position = self.source.pos();
 
            let left = result;
 
            let operation;
 
            if self.has_string(b"<=") {
 
                self.consume_string(b"<=")?;
 
                operation = BinaryOperator::LessThanEqual;
 
            } else if self.has_string(b">=") {
 
                self.consume_string(b">=")?;
 
                operation = BinaryOperator::GreaterThanEqual;
 
            } else if self.has_string(b"<") {
 
                self.consume_string(b"<")?;
 
                operation = BinaryOperator::LessThan;
 
            } else {
 
                self.consume_string(b">")?;
 
                operation = BinaryOperator::GreaterThan;
 
            }
 
            self.consume_whitespace(false)?;
 
            let right = self.consume_shift_expression(h)?;
 
            self.consume_whitespace(false)?;
 
            result = h
 
                .alloc_binary_expression(|this| BinaryExpression {
 
                    this,
 
                    position,
 
                    left,
 
                    operation,
 
                    right,
 
                    parent: ExpressionParent::None,
 
                    concrete_type: ConcreteType::default(),
 
                })
 
                .upcast();
 
        }
 
        Ok(result)
 
    }
 
    fn consume_shift_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let mut result = self.consume_add_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        while self.has_string(b"<<") && !self.has_string(b"<<=")
 
            || self.has_string(b">>") && !self.has_string(b">>=")
 
        {
 
            let position = self.source.pos();
 
            let left = result;
 
            let operation;
 
            if self.has_string(b"<<") {
 
                self.consume_string(b"<<")?;
 
                operation = BinaryOperator::ShiftLeft;
 
            } else {
 
                self.consume_string(b">>")?;
 
                operation = BinaryOperator::ShiftRight;
 
            }
 
            self.consume_whitespace(false)?;
 
            let right = self.consume_add_expression(h)?;
 
            self.consume_whitespace(false)?;
 
            result = h
 
                .alloc_binary_expression(|this| BinaryExpression {
 
                    this,
 
                    position,
 
                    left,
 
                    operation,
 
                    right,
 
                    parent: ExpressionParent::None,
 
                    concrete_type: ConcreteType::default(),
 
                })
 
                .upcast();
 
        }
 
        Ok(result)
 
    }
 
    fn consume_add_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let mut result = self.consume_mul_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        while self.has_string(b"+") && !self.has_string(b"+=")
 
            || self.has_string(b"-") && !self.has_string(b"-=")
 
        {
 
            let position = self.source.pos();
 
            let left = result;
 
            let operation;
 
            if self.has_string(b"+") {
 
                self.consume_string(b"+")?;
 
                operation = BinaryOperator::Add;
 
            } else {
 
                self.consume_string(b"-")?;
 
                operation = BinaryOperator::Subtract;
 
            }
 
            self.consume_whitespace(false)?;
 
            let right = self.consume_mul_expression(h)?;
 
            self.consume_whitespace(false)?;
 
            result = h
 
                .alloc_binary_expression(|this| BinaryExpression {
 
                    this,
 
                    position,
 
                    left,
 
                    operation,
 
                    right,
 
                    parent: ExpressionParent::None,
 
                    concrete_type: ConcreteType::default(),
 
                })
 
                .upcast();
 
        }
 
        Ok(result)
 
    }
 
    fn consume_mul_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let mut result = self.consume_prefix_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        while self.has_string(b"*") && !self.has_string(b"*=")
 
            || self.has_string(b"/") && !self.has_string(b"/=")
 
            || self.has_string(b"%") && !self.has_string(b"%=")
 
        {
 
            let position = self.source.pos();
 
            let left = result;
 
            let operation;
 
            if self.has_string(b"*") {
 
                self.consume_string(b"*")?;
 
                operation = BinaryOperator::Multiply;
 
            } else if self.has_string(b"/") {
 
                self.consume_string(b"/")?;
 
                operation = BinaryOperator::Divide;
 
            } else {
 
                self.consume_string(b"%")?;
 
                operation = BinaryOperator::Remainder;
 
            }
 
            self.consume_whitespace(false)?;
 
            let right = self.consume_prefix_expression(h)?;
 
            self.consume_whitespace(false)?;
 
            result = h
 
                .alloc_binary_expression(|this| BinaryExpression {
 
                    this,
 
                    position,
 
                    left,
 
                    operation,
 
                    right,
 
                    parent: ExpressionParent::None,
 
                    concrete_type: ConcreteType::default(),
 
                })
 
                .upcast();
 
        }
 
        Ok(result)
 
    }
 
    fn consume_prefix_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        if self.has_string(b"+")
 
            || self.has_string(b"-")
 
            || self.has_string(b"~")
 
            || self.has_string(b"!")
 
        {
 
            let position = self.source.pos();
 
            let operation;
 
            if self.has_string(b"+") {
 
                self.consume_string(b"+")?;
 
                if self.has_string(b"+") {
 
                    self.consume_string(b"+")?;
 
                    operation = UnaryOperation::PreIncrement;
 
                } else {
 
                    operation = UnaryOperation::Positive;
 
                }
 
            } else if self.has_string(b"-") {
 
                self.consume_string(b"-")?;
 
                if self.has_string(b"-") {
 
                    self.consume_string(b"-")?;
 
                    operation = UnaryOperation::PreDecrement;
 
                } else {
 
                    operation = UnaryOperation::Negative;
 
                }
 
            } else if self.has_string(b"~") {
 
                self.consume_string(b"~")?;
 
                operation = UnaryOperation::BitwiseNot;
 
            } else {
 
                self.consume_string(b"!")?;
 
                operation = UnaryOperation::LogicalNot;
 
            }
 
            self.consume_whitespace(false)?;
 
            if self.level >= MAX_LEVEL {
 
                return Err(self.error_at_pos("Too deeply nested expression"));
 
            }
 
            self.level += 1;
 
            let result = self.consume_prefix_expression(h);
 
            self.level -= 1;
 
            let expression = result?;
 
            return Ok(h
 
                .alloc_unary_expression(|this| UnaryExpression {
 
                    this,
 
                    position,
 
                    operation,
 
                    expression,
 
                    parent: ExpressionParent::None,
 
                    concrete_type: ConcreteType::default(),
 
                })
 
                .upcast());
 
        }
 
        self.consume_postfix_expression(h)
 
    }
 
    fn consume_postfix_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        let mut result = self.consume_primary_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        while self.has_string(b"++")
 
            || self.has_string(b"--")
 
            || self.has_string(b"[")
 
            || (self.has_string(b".") && !self.has_string(b".."))
 
        {
 
            let mut position = self.source.pos();
 
            if self.has_string(b"++") {
 
                self.consume_string(b"++")?;
 
                let operation = UnaryOperation::PostIncrement;
 
                let expression = result;
 
                self.consume_whitespace(false)?;
 
                result = h
 
                    .alloc_unary_expression(|this| UnaryExpression {
 
                        this,
 
                        position,
 
                        operation,
 
                        expression,
 
                        parent: ExpressionParent::None,
 
                        concrete_type: ConcreteType::default(),
 
                    })
 
                    .upcast();
 
            } else if self.has_string(b"--") {
 
                self.consume_string(b"--")?;
 
                let operation = UnaryOperation::PostDecrement;
 
                let expression = result;
 
                self.consume_whitespace(false)?;
 
                result = h
 
                    .alloc_unary_expression(|this| UnaryExpression {
 
                        this,
 
                        position,
 
                        operation,
 
                        expression,
 
                        parent: ExpressionParent::None,
 
                        concrete_type: ConcreteType::default(),
 
                    })
 
                    .upcast();
 
            } else if self.has_string(b"[") {
 
                self.consume_string(b"[")?;
 
                self.consume_whitespace(false)?;
 
                let subject = result;
 
                let index = self.consume_expression(h)?;
 
                self.consume_whitespace(false)?;
 
                if self.has_string(b"..") || self.has_string(b":") {
 
                    position = self.source.pos();
 
                    if self.has_string(b"..") {
 
                        self.consume_string(b"..")?;
 
                    } else {
 
                        self.consume_string(b":")?;
 
                    }
 
                    self.consume_whitespace(false)?;
 
                    let to_index = self.consume_expression(h)?;
 
                    self.consume_whitespace(false)?;
 
                    result = h
 
                        .alloc_slicing_expression(|this| SlicingExpression {
 
                            this,
 
                            position,
 
                            subject,
 
                            from_index: index,
 
                            to_index,
 
                            parent: ExpressionParent::None,
 
                            concrete_type: ConcreteType::default(),
 
                        })
 
                        .upcast();
 
                } else {
 
                    result = h
 
                        .alloc_indexing_expression(|this| IndexingExpression {
 
                            this,
 
                            position,
 
                            subject,
 
                            index,
 
                            parent: ExpressionParent::None,
 
                            concrete_type: ConcreteType::default(),
 
                        })
 
                        .upcast();
 
                }
 
                self.consume_string(b"]")?;
 
                self.consume_whitespace(false)?;
 
            } else {
 
                assert!(self.has_string(b"."));
 
                self.consume_string(b".")?;
 
                self.consume_whitespace(false)?;
 
                let subject = result;
 
                let field;
 
                if self.has_keyword(b"length") {
 
                    self.consume_keyword(b"length")?;
 
                    field = Field::Length;
 
                } else {
 
                    field = Field::Symbolic(self.consume_identifier()?);
 
                }
 
                result = h
 
                    .alloc_select_expression(|this| SelectExpression {
 
                        this,
 
                        position,
 
                        subject,
 
                        field,
 
                        parent: ExpressionParent::None,
 
                        concrete_type: ConcreteType::default(),
 
                    })
 
                    .upcast();
 
            }
 
        }
 
        Ok(result)
 
    }
 
    fn consume_primary_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
 
        if self.has_string(b"(") {
 
            return self.consume_paren_expression(h);
 
        }
 
        if self.has_string(b"{") {
 
            return Ok(self.consume_array_expression(h)?.upcast());
 
        }
 
        if self.has_constant()
 
            || self.has_keyword(b"null")
 
            || self.has_keyword(b"true")
 
            || self.has_keyword(b"false")
 
        {
 
            return Ok(self.consume_constant_expression(h)?.upcast());
 
        if self.has_builtin_literal() {
 
            return Ok(self.consume_builtin_literal_expression(h)?.upcast());
 
        }
 
        if self.has_struct_literal() {
 
            return Ok(self.consume_struct_literal_expression(h)?.upcast());
 
        }
 
        if self.has_call_expression() {
 
            return Ok(self.consume_call_expression(h)?.upcast());
 
        }
 
        Ok(self.consume_variable_expression(h)?.upcast())
 
    }
 
    fn consume_array_expression(&mut self, h: &mut Heap) -> Result<ArrayExpressionId, ParseError2> {
 
        let position = self.source.pos();
 
        let mut elements = Vec::new();
 
        self.consume_string(b"{")?;
 
        self.consume_whitespace(false)?;
 
        if !self.has_string(b"}") {
 
            while self.source.next().is_some() {
 
                elements.push(self.consume_expression(h)?);
 
                self.consume_whitespace(false)?;
 
                if self.has_string(b"}") {
 
                    break;
 
                }
 
                self.consume_string(b",")?;
 
                self.consume_whitespace(false)?;
 
            }
 
        }
 
        self.consume_string(b"}")?;
 
        Ok(h.alloc_array_expression(|this| ArrayExpression {
 
            this,
 
            position,
 
            elements,
 
            parent: ExpressionParent::None,
 
            concrete_type: ConcreteType::default(),
 
        }))
 
    }
 
    fn has_constant(&self) -> bool {
 
    fn has_builtin_literal(&self) -> bool {
 
        is_constant(self.source.next())
 
            || self.has_keyword(b"null")
 
            || self.has_keyword(b"true")
 
            || self.has_keyword(b"false")
 
    }
 
    fn consume_constant_expression(
 
    fn consume_builtin_literal_expression(
 
        &mut self,
 
        h: &mut Heap,
 
    ) -> Result<ConstantExpressionId, ParseError2> {
 
    ) -> Result<LiteralExpressionId, ParseError2> {
 
        let position = self.source.pos();
 
        let value;
 
        if self.has_keyword(b"null") {
 
            self.consume_keyword(b"null")?;
 
            value = Constant::Null;
 
            value = Literal::Null;
 
        } else if self.has_keyword(b"true") {
 
            self.consume_keyword(b"true")?;
 
            value = Constant::True;
 
            value = Literal::True;
 
        } else if self.has_keyword(b"false") {
 
            self.consume_keyword(b"false")?;
 
            value = Constant::False;
 
            value = Literal::False;
 
        } else if self.source.next() == Some(b'\'') {
 
            self.source.consume();
 
            let mut data = Vec::new();
 
            let mut next = self.source.next();
 
            while next != Some(b'\'') && (is_vchar(next) || next == Some(b' ')) {
 
                data.push(next.unwrap());
 
                self.source.consume();
 
                next = self.source.next();
 
            }
 
            if next != Some(b'\'') || data.is_empty() {
 
                return Err(self.error_at_pos("Expected character constant"));
 
            }
 
            self.source.consume();
 
            value = Constant::Character(data);
 
            value = Literal::Character(data);
 
        } else {
 
            if !self.has_integer() {
 
                return Err(self.error_at_pos("Expected integer constant"));
 
            }
 

	
 
            value = Constant::Integer(self.consume_integer()?);
 
            value = Literal::Integer(self.consume_integer()?);
 
        }
 
        Ok(h.alloc_constant_expression(|this| ConstantExpression {
 
        Ok(h.alloc_literal_expression(|this| LiteralExpression {
 
            this,
 
            position,
 
            value,
 
            parent: ExpressionParent::None,
 
            concrete_type: ConcreteType::default(),
 
        }))
 
    }
 

	
 
    fn has_struct_literal(&mut self) -> bool {
 
        // A struct literal is written as:
 
        //      namespace::StructName<maybe_one_of_these, auto>{ field: expr }
 
        // We will parse up until the opening brace to see if we're dealing with
 
        // a struct literal.
 
        let backup_pos = self.source.pos();
 
        let result = self.consume_namespaced_identifier_spilled().is_ok() &&
 
            self.consume_whitespace(false).is_ok() &&
 
            self.maybe_consume_poly_args_spilled_without_pos_recovery() &&
 
            self.consume_whitespace(false).is_ok() &&
 
            self.source.next() == Some(b'{');
 

	
 
        self.source.seek(backup_pos);
 
        return result;
 
    }
 

	
 
    fn consume_struct_literal_expression(&mut self, h: &mut Heap) -> Result<LiteralExpressionId, ParseError2> {
 
        // Consume identifier and polymorphic arguments
 
        let position = self.source.pos();
 
        let identifier = self.consume_namespaced_identifier()?;
 
        self.consume_whitespace(false)?;
 
        let poly_args = self.consume_polymorphic_args(h, true)?;
 
        self.consume_whitespace(false)?;
 

	
 
        // Consume fields
 
        let fields = match self.consume_comma_separated(
 
            h, b'{', b'}', "Expected the end of the list of struct fields",
 
            |lexer, heap| {
 
                let identifier = lexer.consume_identifier()?;
 
                lexer.consume_whitespace(false)?;
 
                lexer.consume_string(b":")?;
 
                lexer.consume_whitespace(false)?;
 
                let value = lexer.consume_expression(heap)?;
 

	
 
                Ok(LiteralStructField{ identifier, value, field_idx: 0 })
 
            }
 
        )? {
 
            Some(fields) => fields,
 
            None => return Err(ParseError2::new_error(
 
                self.source, self.source.pos(),
 
                "A struct literal must be followed by its field values"
 
            ))
 
        };
 

	
 
        Ok(h.alloc_literal_expression(|this| LiteralExpression{
 
            this,
 
            position,
 
            value: Literal::Struct(LiteralStruct{
 
                identifier,
 
                poly_args,
 
                fields,
 
                definition: None,
 
            }),
 
            parent: ExpressionParent::None,
 
            concrete_type: Default::default()
 
        }))
 
    }
 

	
 
    fn has_call_expression(&mut self) -> bool {
 
        // We need to prevent ambiguity with various operators (because we may
 
        // be specifying polymorphic variables) and variables.
 
        if self.has_builtin_keyword() {
 
            return true;
 
        }
 

	
 
        let backup_pos = self.source.pos();
 
        let mut result = false;
 

	
 
        if self.consume_namespaced_identifier_spilled().is_ok() &&
 
            self.consume_whitespace(false).is_ok() &&
 
            self.maybe_consume_poly_args_spilled_without_pos_recovery() &&
 
            self.consume_whitespace(false).is_ok() &&
 
            self.source.next() == Some(b'(') {
 
            // Seems like we have a function call or an enum literal
 
            result = true;
 
        }
 

	
 
        self.source.seek(backup_pos);
 
        return result;
 
    }
 
    fn consume_call_expression(&mut self, h: &mut Heap) -> Result<CallExpressionId, ParseError2> {
 
        let position = self.source.pos();
 

	
 
        // Consume method identifier
 
        let method;
 
        if self.has_keyword(b"get") {
 
            self.consume_keyword(b"get")?;
 
            method = Method::Get;
 
        } else if self.has_keyword(b"put") {
 
            self.consume_keyword(b"put")?;
 
            method = Method::Put;
 
        } else if self.has_keyword(b"fires") {
 
            self.consume_keyword(b"fires")?;
 
            method = Method::Fires;
 
        } else if self.has_keyword(b"create") {
 
            self.consume_keyword(b"create")?;
 
            method = Method::Create;
 
        } else {
 
            let identifier = self.consume_namespaced_identifier()?;
 
            method = Method::Symbolic(MethodSymbolic{
 
                identifier,
 
                definition: None
 
            })
 
        }
 

	
 
        // Consume polymorphic arguments
 
        self.consume_whitespace(false)?;
 
        let poly_args = self.consume_polymorphic_args(h, true)?;
 

	
 
        // Consume arguments to call
 
        self.consume_whitespace(false)?;
 
        let mut arguments = Vec::new();
 
        self.consume_string(b"(")?;
 
        self.consume_whitespace(false)?;
 
        if !self.has_string(b")") {
 
            // TODO: allow trailing comma
 
            while self.source.next().is_some() {
 
                arguments.push(self.consume_expression(h)?);
 
                self.consume_whitespace(false)?;
 
                if self.has_string(b")") {
 
                    break;
 
                }
 
                self.consume_string(b",")?;
 
                self.consume_whitespace(false)?
 
            }
 
        }
 
        self.consume_string(b")")?;
 
        Ok(h.alloc_call_expression(|this| CallExpression {
 
            this,
 
            position,
 
            method,
 
            arguments,
 
            poly_args,
 
            parent: ExpressionParent::None,
 
            concrete_type: ConcreteType::default(),
 
        }))
 
    }
 
    fn consume_variable_expression(
 
        &mut self,
 
        h: &mut Heap,
 
    ) -> Result<VariableExpressionId, ParseError2> {
 
        let position = self.source.pos();
 
        let identifier = self.consume_namespaced_identifier()?;
 
        Ok(h.alloc_variable_expression(|this| VariableExpression {
 
            this,
 
            position,
 
            identifier,
 
            declaration: None,
 
            parent: ExpressionParent::None,
 
            concrete_type: ConcreteType::default(),
 
        }))
 
    }
 

	
 
    // ====================
 
    // Statements
 
    // ====================
 

	
 
    /// Consumes any kind of statement from the source and will error if it
 
    /// did not encounter a statement. Will also return an error if the
 
    /// statement is nested too deeply.
 
    ///
 
    /// `wrap_in_block` may be set to true to ensure that the parsed statement
 
    /// will be wrapped in a block statement if it is not already a block
 
    /// statement. This is used to ensure that all `if`, `while` and `sync`
 
    /// statements have a block statement as body.
 
    fn consume_statement(&mut self, h: &mut Heap, wrap_in_block: bool) -> Result<StatementId, ParseError2> {
 
        if self.level >= MAX_LEVEL {
 
            return Err(self.error_at_pos("Too deeply nested statement"));
 
        }
 
        self.level += 1;
 
        let result = self.consume_statement_impl(h, wrap_in_block);
 
        self.level -= 1;
 
        result
 
    }
 
    fn has_label(&mut self) -> bool {
 
        // To prevent ambiguity with expression statements consisting only of an
 
        // identifier or a namespaced identifier, we look ahead and match on the
 
        // *single* colon that signals a labeled statement.
 
        let backup_pos = self.source.pos();
 
        let mut result = false;
 
        if self.consume_identifier_spilled().is_ok() {
 
            // next character is ':', second character is NOT ':'
 
            result = Some(b':') == self.source.next() && Some(b':') != self.source.lookahead(1)
 
        }
 
        self.source.seek(backup_pos);
 
        return result;
 
    }
 
    fn consume_statement_impl(&mut self, h: &mut Heap, wrap_in_block: bool) -> Result<StatementId, ParseError2> {
 
        // Parse and allocate statement
 
        let mut must_wrap = true;
 
        let mut stmt_id = if self.has_string(b"{") {
 
            must_wrap = false;
 
            self.consume_block_statement(h)?
 
        } else if self.has_keyword(b"skip") {
 
            must_wrap = false;
 
            self.consume_skip_statement(h)?.upcast()
 
        } else if self.has_keyword(b"if") {
 
            self.consume_if_statement(h)?.upcast()
 
        } else if self.has_keyword(b"while") {
 
            self.consume_while_statement(h)?.upcast()
 
        } else if self.has_keyword(b"break") {
 
            self.consume_break_statement(h)?.upcast()
 
        } else if self.has_keyword(b"continue") {
 
            self.consume_continue_statement(h)?.upcast()
 
        } else if self.has_keyword(b"synchronous") {
 
            self.consume_synchronous_statement(h)?.upcast()
 
        } else if self.has_keyword(b"return") {
 
            self.consume_return_statement(h)?.upcast()
 
        } else if self.has_keyword(b"assert") {
 
            self.consume_assert_statement(h)?.upcast()
 
        } else if self.has_keyword(b"goto") {
 
            self.consume_goto_statement(h)?.upcast()
 
        } else if self.has_keyword(b"new") {
 
            self.consume_new_statement(h)?.upcast()
 
        } else if self.has_label() {
 
            self.consume_labeled_statement(h)?.upcast()
 
        } else {
 
            self.consume_expression_statement(h)?.upcast()
 
        };
 

	
 
        // Wrap if desired and if needed
 
        if must_wrap && wrap_in_block {
 
            let position = h[stmt_id].position();
 
            let block_wrapper = h.alloc_block_statement(|this| BlockStatement{
 
                this,
 
                position,
 
                statements: vec![stmt_id],
 
                parent_scope: None,
 
                relative_pos_in_parent: 0,
 
                locals: Vec::new(),
 
                labels: Vec::new()
 
            });
 

	
 
            stmt_id = block_wrapper.upcast();
 
        }
 

	
 
        Ok(stmt_id)
 
    }
 
    fn has_local_statement(&mut self) -> bool {
 
        /* To avoid ambiguity, we look ahead to find either the
 
        channel keyword that signals a variable declaration, or
 
        a type annotation followed by another identifier.
 
        Example:
 
          my_type[] x = {5}; // memory statement
 
          my_var[5] = x; // assignment expression, expression statement
 
        Note how both the local and the assignment
 
        start with arbitrary identifier followed by [. */
 
        if self.has_keyword(b"channel") {
 
            return true;
 
        }
 
        if self.has_statement_keyword() {
 
            return false;
 
        }
 
        let backup_pos = self.source.pos();
 
        let mut result = false;
 
        if self.maybe_consume_type_spilled_without_pos_recovery() {
 
            // We seem to have a valid type, do we now have an identifier?
 
            if self.consume_whitespace(true).is_ok() {
 
                result = self.has_identifier();
 
            }
 
        }
 

	
 
        self.source.seek(backup_pos);
 
        return result;
 
    }
 
    fn consume_block_statement(&mut self, h: &mut Heap) -> Result<StatementId, ParseError2> {
 
        let position = self.source.pos();
 
        let mut statements = Vec::new();
 
        self.consume_string(b"{")?;
 
        self.consume_whitespace(false)?;
 
        while self.has_local_statement() {
 
            let (local_id, stmt_id) = self.consume_local_statement(h)?;
 
            statements.push(local_id.upcast());
 
            if let Some(stmt_id) = stmt_id {
 
                statements.push(stmt_id.upcast());
 
            }
 
            self.consume_whitespace(false)?;
 
        }
 
        while !self.has_string(b"}") {
 
            statements.push(self.consume_statement(h, false)?);
 
            self.consume_whitespace(false)?;
 
        }
 
        self.consume_string(b"}")?;
 
        if statements.is_empty() {
 
            Ok(h.alloc_skip_statement(|this| SkipStatement { this, position, next: None }).upcast())
 
        } else {
 
            Ok(h.alloc_block_statement(|this| BlockStatement {
 
                this,
 
                position,
 
                statements,
 
                parent_scope: None,
 
                relative_pos_in_parent: 0,
 
                locals: Vec::new(),
 
                labels: Vec::new(),
 
            })
 
            .upcast())
 
        }
 
    }
 
    fn consume_local_statement(&mut self, h: &mut Heap) -> Result<(LocalStatementId, Option<ExpressionStatementId>), ParseError2> {
 
        if self.has_keyword(b"channel") {
 
            let local_id = self.consume_channel_statement(h)?.upcast();
 
            Ok((local_id, None))
 
        } else {
 
            let (memory_id, stmt_id) = self.consume_memory_statement(h)?;
 
            Ok((memory_id.upcast(), Some(stmt_id)))
 
        }
 
    }
 
    fn consume_channel_statement(
 
        &mut self,
 
        h: &mut Heap,
 
    ) -> Result<ChannelStatementId, ParseError2> {
 
        // Consume channel statement and polymorphic argument if specified
 
        // Consume channel statement and polymorphic argument if specified.
 
        // Needs a tiny bit of special parsing to ensure the right amount of
 
        // whitespace is present.
 
        let position = self.source.pos();
 
        self.consume_keyword(b"channel")?;
 

	
 
        let expect_whitespace = self.source.next() != Some(b'<');
 
        self.consume_whitespace(expect_whitespace)?;
 
        let poly_args = self.consume_polymorphic_args(h, true)?;
 
        let poly_arg_id = match poly_args.len() {
 
            0 => h.alloc_parser_type(|this| ParserType{
 
                this, pos: position.clone(), variant: ParserTypeVariant::Inferred,
 
            }),
 
            1 => poly_args[0],
 
            _ => return Err(ParseError2::new_error(
 
                &self.source, self.source.pos(),
 
                "port construction using 'channel' accepts up to 1 polymorphic argument"
 
            ))
 
        };
 
        self.consume_whitespace(true)?;
 
        self.consume_whitespace(false)?;
 

	
 
        // Consume the output port
 
        let out_parser_type = h.alloc_parser_type(|this| ParserType{
 
            this, pos: position.clone(), variant: ParserTypeVariant::Output(poly_arg_id)
 
        });
 
        let out_identifier = self.consume_identifier()?;
 

	
 
        // Consume the "->" syntax
 
        self.consume_whitespace(false)?;
 
        self.consume_string(b"->")?;
 
        self.consume_whitespace(false)?;
 

	
 
        // Consume the input port
 
        // TODO: Unsure about this, both ports refer to the same ParserType, is this ok?
 
        let in_parser_type = h.alloc_parser_type(|this| ParserType{
 
            this, pos: position.clone(), variant: ParserTypeVariant::Input(poly_arg_id)
 
        });
 
        let in_identifier = self.consume_identifier()?;
 
        self.consume_whitespace(false)?;
 
        self.consume_string(b";")?;
 
        let out_port = h.alloc_local(|this| Local {
 
            this,
 
            position,
 
            parser_type: out_parser_type,
 
            identifier: out_identifier,
 
            relative_pos_in_block: 0
 
        });
 
        let in_port = h.alloc_local(|this| Local {
 
            this,
 
            position,
 
            parser_type: in_parser_type,
 
            identifier: in_identifier,
 
            relative_pos_in_block: 0
 
        });
 
        Ok(h.alloc_channel_statement(|this| ChannelStatement {
 
            this,
 
            position,
 
            from: out_port,
 
            to: in_port,
 
            relative_pos_in_block: 0,
 
            next: None,
 
        }))
 
    }
 
    fn consume_memory_statement(&mut self, h: &mut Heap) -> Result<(MemoryStatementId, ExpressionStatementId), ParseError2> {
 
        let position = self.source.pos();
 
        let parser_type = self.consume_type2(h, true)?;
 
        self.consume_whitespace(true)?;
 
        let identifier = self.consume_identifier()?;
 
        self.consume_whitespace(false)?;
 
        let assignment_position = self.source.pos();
 
        self.consume_string(b"=")?;
 
        self.consume_whitespace(false)?;
 
        let initial = self.consume_expression(h)?;
 
        let variable = h.alloc_local(|this| Local {
 
            this,
 
            position,
 
            parser_type,
 
            identifier: identifier.clone(),
 
            relative_pos_in_block: 0
 
        });
 
        self.consume_whitespace(false)?;
 
        self.consume_string(b";")?;
 

	
 
        // Transform into the variable declaration, followed by an assignment
 
        let memory_stmt_id = h.alloc_memory_statement(|this| MemoryStatement {
 
            this,
 
            position,
 
            variable,
 
            next: None,
 
        });
 
        let variable_expr_id = h.alloc_variable_expression(|this| VariableExpression{
 
            this,
 
            position: identifier.position.clone(),
 
            identifier: NamespacedIdentifier {
 
                position: identifier.position.clone(),
 
                num_namespaces: 1,
 
                value: identifier.value.clone(),
 
            },
 
            declaration: None,
 
            parent: ExpressionParent::None,
 
            concrete_type: Default::default()
 
        });
 
        let assignment_expr_id = h.alloc_assignment_expression(|this| AssignmentExpression{
 
            this,
 
            position: assignment_position,
 
            left: variable_expr_id.upcast(),
 
            operation: AssignmentOperator::Set,
 
            right: initial,
 
            parent: ExpressionParent::None,
 
            concrete_type: Default::default()
 
        });
 
        let assignment_stmt_id = h.alloc_expression_statement(|this| ExpressionStatement{
 
            this,
 
            position,
 
            expression: assignment_expr_id.upcast(),
 
            next: None
 
        });
 
        Ok((memory_stmt_id, assignment_stmt_id))
 
    }
 
    fn consume_labeled_statement(
 
        &mut self,
 
        h: &mut Heap,
 
    ) -> Result<LabeledStatementId, ParseError2> {
 
        let position = self.source.pos();
 
        let label = self.consume_identifier()?;
 
        self.consume_whitespace(false)?;
 
        self.consume_string(b":")?;
 
        self.consume_whitespace(false)?;
 
        let body = self.consume_statement(h, false)?;
 
        Ok(h.alloc_labeled_statement(|this| LabeledStatement {
 
            this,
 
            position,
 
            label,
 
            body,
 
            relative_pos_in_block: 0,
 
            in_sync: None,
 
        }))
 
    }
 
    fn consume_skip_statement(&mut self, h: &mut Heap) -> Result<SkipStatementId, ParseError2> {
 
        let position = self.source.pos();
 
        self.consume_keyword(b"skip")?;
 
        self.consume_whitespace(false)?;
 
        self.consume_string(b";")?;
 
        Ok(h.alloc_skip_statement(|this| SkipStatement { this, position, next: None }))
 
    }
 
    fn consume_if_statement(&mut self, h: &mut Heap) -> Result<IfStatementId, ParseError2> {
 
        let position = self.source.pos();
 
        self.consume_keyword(b"if")?;
 
        self.consume_whitespace(false)?;
 
        let test = self.consume_paren_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        let true_body = self.consume_statement(h, true)?;
 
        self.consume_whitespace(false)?;
 
        let false_body = if self.has_keyword(b"else") {
 
            self.consume_keyword(b"else")?;
 
            self.consume_whitespace(false)?;
 
            self.consume_statement(h, true)?
 
        } else {
 
            h.alloc_skip_statement(|this| SkipStatement { this, position, next: None }).upcast()
 
        };
 
        Ok(h.alloc_if_statement(|this| IfStatement { this, position, test, true_body, false_body, end_if: None }))
 
    }
 
    fn consume_while_statement(&mut self, h: &mut Heap) -> Result<WhileStatementId, ParseError2> {
 
        let position = self.source.pos();
 
        self.consume_keyword(b"while")?;
 
        self.consume_whitespace(false)?;
 
        let test = self.consume_paren_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        let body = self.consume_statement(h, true)?;
 
        Ok(h.alloc_while_statement(|this| WhileStatement {
 
            this,
 
            position,
 
            test,
 
            body,
 
            end_while: None,
 
            in_sync: None,
 
        }))
 
    }
 
    fn consume_break_statement(&mut self, h: &mut Heap) -> Result<BreakStatementId, ParseError2> {
 
        let position = self.source.pos();
 
        self.consume_keyword(b"break")?;
 
        self.consume_whitespace(false)?;
 
        let label;
 
        if self.has_identifier() {
 
            label = Some(self.consume_identifier()?);
 
            self.consume_whitespace(false)?;
 
        } else {
 
            label = None;
 
        }
 
        self.consume_string(b";")?;
 
        Ok(h.alloc_break_statement(|this| BreakStatement { this, position, label, target: None }))
 
    }
 
    fn consume_continue_statement(
 
        &mut self,
 
        h: &mut Heap,
 
    ) -> Result<ContinueStatementId, ParseError2> {
 
        let position = self.source.pos();
 
        self.consume_keyword(b"continue")?;
 
        self.consume_whitespace(false)?;
 
        let label;
 
        if self.has_identifier() {
 
            label = Some(self.consume_identifier()?);
 
            self.consume_whitespace(false)?;
 
        } else {
 
            label = None;
 
        }
 
        self.consume_string(b";")?;
 
        Ok(h.alloc_continue_statement(|this| ContinueStatement {
 
            this,
 
            position,
 
            label,
 
            target: None,
 
        }))
 
    }
 
    fn consume_synchronous_statement(
 
        &mut self,
 
        h: &mut Heap,
 
    ) -> Result<SynchronousStatementId, ParseError2> {
 
        let position = self.source.pos();
 
        self.consume_keyword(b"synchronous")?;
 
        self.consume_whitespace(false)?;
 
        // TODO: What was the purpose of this? Seems superfluous and confusing?
 
        // let mut parameters = Vec::new();
 
        // if self.has_string(b"(") {
 
        //     self.consume_parameters(h, &mut parameters)?;
 
        //     self.consume_whitespace(false)?;
 
        // } else if !self.has_keyword(b"skip") && !self.has_string(b"{") {
 
        //     return Err(self.error_at_pos("Expected block statement"));
 
        // }
 
        let body = self.consume_statement(h, true)?;
 
        Ok(h.alloc_synchronous_statement(|this| SynchronousStatement {
 
            this,
 
            position,
 
            body,
 
            end_sync: None,
 
            parent_scope: None,
 
        }))
 
    }
 
    fn consume_return_statement(&mut self, h: &mut Heap) -> Result<ReturnStatementId, ParseError2> {
 
        let position = self.source.pos();
 
        self.consume_keyword(b"return")?;
 
        self.consume_whitespace(false)?;
 
        let expression = if self.has_string(b"(") {
 
            self.consume_paren_expression(h)
 
        } else {
 
            self.consume_expression(h)
 
        }?;
 
        self.consume_whitespace(false)?;
 
        self.consume_string(b";")?;
 
        Ok(h.alloc_return_statement(|this| ReturnStatement { this, position, expression }))
 
    }
 
    fn consume_assert_statement(&mut self, h: &mut Heap) -> Result<AssertStatementId, ParseError2> {
 
        let position = self.source.pos();
 
        self.consume_keyword(b"assert")?;
 
        self.consume_whitespace(false)?;
 
        let expression = if self.has_string(b"(") {
 
            self.consume_paren_expression(h)
 
        } else {
 
            self.consume_expression(h)
 
        }?;
 
        self.consume_whitespace(false)?;
 
        self.consume_string(b";")?;
 
        Ok(h.alloc_assert_statement(|this| AssertStatement {
 
            this,
 
            position,
 
            expression,
 
            next: None,
 
        }))
 
    }
 
    fn consume_goto_statement(&mut self, h: &mut Heap) -> Result<GotoStatementId, ParseError2> {
 
        let position = self.source.pos();
 
        self.consume_keyword(b"goto")?;
 
        self.consume_whitespace(false)?;
 
        let label = self.consume_identifier()?;
 
        self.consume_whitespace(false)?;
 
        self.consume_string(b";")?;
 
        Ok(h.alloc_goto_statement(|this| GotoStatement { this, position, label, target: None }))
 
    }
 
    fn consume_new_statement(&mut self, h: &mut Heap) -> Result<NewStatementId, ParseError2> {
 
        let position = self.source.pos();
 
        self.consume_keyword(b"new")?;
 
        self.consume_whitespace(false)?;
 
        let expression = self.consume_call_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        self.consume_string(b";")?;
 
        Ok(h.alloc_new_statement(|this| NewStatement { this, position, expression, next: None }))
 
    }
 
    fn consume_expression_statement(
 
        &mut self,
 
        h: &mut Heap,
 
    ) -> Result<ExpressionStatementId, ParseError2> {
 
        let position = self.source.pos();
 
        let expression = self.consume_expression(h)?;
 
        self.consume_whitespace(false)?;
 
        self.consume_string(b";")?;
 
        Ok(h.alloc_expression_statement(|this| ExpressionStatement {
 
            this,
 
            position,
 
            expression,
 
            next: None,
 
        }))
 
    }
 

	
 
    // ====================
 
    // Symbol definitions
 
    // ====================
 

	
 
    fn has_symbol_definition(&self) -> bool {
 
        self.has_keyword(b"composite")
 
            || self.has_keyword(b"primitive")
 
            || self.has_type_keyword()
 
            || self.has_identifier()
 
    }
 
    fn consume_symbol_definition(&mut self, h: &mut Heap) -> Result<DefinitionId, ParseError2> {
 
        if self.has_keyword(b"struct") {
 
            Ok(self.consume_struct_definition(h)?.upcast())
 
        } else if self.has_keyword(b"enum") {
 
            Ok(self.consume_enum_definition(h)?.upcast())
 
        } else if self.has_keyword(b"composite") || self.has_keyword(b"primitive") {
 
            Ok(self.consume_component_definition(h)?.upcast())
 
        } else {
 
            Ok(self.consume_function_definition(h)?.upcast())
 
        }
 
    }
 
    fn consume_struct_definition(&mut self, h: &mut Heap) -> Result<StructId, ParseError2> {
 
        // Parse "struct" keyword, optional polyvars and its identifier
 
        let struct_pos = self.source.pos();
 
        self.consume_keyword(b"struct")?;
 
        self.consume_whitespace(true)?;
 
        let struct_ident = self.consume_identifier()?;
 
        self.consume_whitespace(false)?;
 
        let poly_vars = self.consume_polymorphic_vars()?;
 
        let poly_vars = self.consume_polymorphic_vars(h)?;
 
        self.consume_whitespace(false)?;
 

	
 
        // Parse struct fields
 
        self.consume_string(b"{")?;
 
        let mut next = self.source.next();
 
        let mut fields = Vec::new();
 
        while next.is_some() {
 
            let char = next.unwrap();
 
            if char == b'}' {
 
                break;
 
            }
 

	
 
            // Consume field definition
 
            self.consume_whitespace(false)?;
 
            let field_position = self.source.pos();
 
            let field_parser_type = self.consume_type2(h, false)?;
 
            self.consume_whitespace(true)?;
 
            let field_ident = self.consume_identifier()?;
 
            self.consume_whitespace(false)?;
 

	
 
            fields.push(StructFieldDefinition{
 
                position: field_position,
 
                field: field_ident,
 
                parser_type: field_parser_type,
 
            });
 

	
 
            // If we have a comma, then we may or may not have another field
 
            // definition. Otherwise we expect the struct to be fully defined
 
            // and expect a closing brace
 
            next = self.source.next();
 
            if let Some(b',') = next {
 
                self.source.consume();
 
                self.consume_whitespace(false)?;
 
                next = self.source.next();
 
            } else {
 
                break;
 
            }
 
        }
 

	
 
        // End of struct definition, so we expect a closing brace
 
        self.consume_string(b"}")?;
 
        let fields = match self.consume_comma_separated(
 
            h, b'{', b'}', "Expected the end of the list of struct fields",
 
            |lexer, heap| {
 
                let position = lexer.source.pos();
 
                let parser_type = lexer.consume_type2(heap, false)?;
 
                lexer.consume_whitespace(true)?;
 
                let field = lexer.consume_identifier()?;
 

	
 
                Ok(StructFieldDefinition{ position, field, parser_type })
 
            }
 
        )? {
 
            Some(fields) => fields,
 
            None => return Err(ParseError2::new_error(
 
                self.source, struct_pos,
 
                "An struct definition must be followed by its fields"
 
            )),
 
        };
 

	
 
        // Valid struct definition
 
        Ok(h.alloc_struct_definition(|this| StructDefinition{
 
            this,
 
            position: struct_pos,
 
            identifier: struct_ident,
 
            poly_vars,
 
            fields,
 
        }))
 
    }
 
    fn consume_enum_definition(&mut self, h: &mut Heap) -> Result<EnumId, ParseError2> {
 
        // Parse "enum" keyword, optional polyvars and its identifier
 
        let enum_pos = self.source.pos();
 
        self.consume_keyword(b"enum")?;
 
        self.consume_whitespace(true)?;
 
        let enum_ident = self.consume_identifier()?;
 
        self.consume_whitespace(false)?;
 
        let poly_vars = self.consume_polymorphic_vars()?;
 
        let poly_vars = self.consume_polymorphic_vars(h)?;
 
        self.consume_whitespace(false)?;
 

	
 
        // Parse enum variants
 
        self.consume_string(b"{")?;
 
        let mut next = self.source.next();
 
        let mut variants = Vec::new();
 
        while next.is_some() {
 
            let char = next.unwrap();
 
            if char == b'}' {
 
                break;
 
            }
 

	
 
            // Consume variant identifier
 
            self.consume_whitespace(false)?;
 
            let variant_position = self.source.pos();
 
            let variant_ident = self.consume_identifier()?;
 
            self.consume_whitespace(false)?;
 
        let variants = match self.consume_comma_separated(
 
            h, b'{', b'}', "Expected end of enum variant list",
 
            |lexer, heap| {
 
                // Variant identifier
 
                let position = lexer.source.pos();
 
                let identifier = lexer.consume_identifier()?;
 
                lexer.consume_whitespace(false)?;
 

	
 
            // Consume variant (tag) value: may be nothing, in which case it is
 
            // assigned automatically, may be a constant integer, or an embedded
 
            // type as value, resulting in a tagged union
 
            next = self.source.next();
 
            let variant_value = if let Some(b',') = next {
 
                // Optional variant value/type
 
                let next = lexer.source.next();
 
                let value = match next {
 
                    Some(b',') => {
 
                        // Do not consume, let `consume_comma_separated` handle
 
                        // the next item
 
                        EnumVariantValue::None
 
            } else if let Some(b'=') = next {
 
                self.source.consume();
 
                self.consume_whitespace(false)?;
 
                if !self.has_integer() {
 
                    return Err(self.error_at_pos("expected integer"));
 
                    },
 
                    Some(b'=') => {
 
                        // Integer value
 
                        lexer.source.consume();
 
                        lexer.consume_whitespace(false)?;
 
                        if !lexer.has_integer() {
 
                            return Err(lexer.error_at_pos("expected integer"))
 
                        }
 
                        let value = lexer.consume_integer()?;
 
                        EnumVariantValue::Integer(value)
 
                    },
 
                    Some(b'(') => {
 
                        // Embedded type
 
                        lexer.source.consume();
 
                        lexer.consume_whitespace(false)?;
 
                        let embedded_type = lexer.consume_type2(heap, false)?;
 
                        lexer.consume_whitespace(false)?;
 
                        lexer.consume_string(b")")?;
 
                        EnumVariantValue::Type(embedded_type)
 
                    },
 
                    _ => {
 
                        return Err(lexer.error_at_pos("Expected ',', '=', or '('"));
 
                    }
 
                let variant_int = self.consume_integer()?;
 
                self.consume_whitespace(false)?;
 
                EnumVariantValue::Integer(variant_int)
 
            } else if let Some(b'(') = next {
 
                self.source.consume();
 
                self.consume_whitespace(false)?;
 
                let variant_type = self.consume_type2(h, false)?;
 
                self.consume_whitespace(false)?;
 
                self.consume_string(b")")?;
 
                self.consume_whitespace(false)?;
 
                EnumVariantValue::Type(variant_type)
 
            } else {
 
                return Err(self.error_at_pos("expected ',', '=', or '('"));
 
                };
 

	
 
            variants.push(EnumVariantDefinition{
 
                position: variant_position,
 
                identifier: variant_ident,
 
                value: variant_value
 
            });
 

	
 
            // If we have a comma, then we may or may not have another variant,
 
            // otherwise we expect the enum is fully defined
 
            next = self.source.next();
 
            if let Some(b',') = next {
 
                self.source.consume();
 
                self.consume_whitespace(false)?;
 
                next = self.source.next();
 
            } else {
 
                break;
 
            }
 
        }
 

	
 
        self.consume_string(b"}")?;
 

	
 
        // An enum without variants is somewhat valid, but completely useless
 
        // within the language
 
        if variants.is_empty() {
 
            return Err(ParseError2::new_error(self.source, enum_pos, "enum definition without variants"));
 
                Ok(EnumVariantDefinition{ position, identifier, value })
 
            }
 
        )? {
 
            Some(variants) => variants,
 
            None => return Err(ParseError2::new_error(
 
                self.source, enum_pos,
 
                "An enum definition must be followed by its variants"
 
            )),
 
        };
 

	
 
        Ok(h.alloc_enum_definition(|this| EnumDefinition{
 
            this,
 
            position: enum_pos,
 
            identifier: enum_ident,
 
            poly_vars,
 
            variants,
 
        }))
 
    }
 
    fn consume_component_definition(&mut self, h: &mut Heap) -> Result<ComponentId, ParseError2> {
 
        // TODO: Cleanup
 
        if self.has_keyword(b"composite") {
 
            Ok(self.consume_composite_definition(h)?)
 
        } else {
 
            Ok(self.consume_primitive_definition(h)?)
 
        }
 
    }
 
    fn consume_composite_definition(&mut self, h: &mut Heap) -> Result<ComponentId, ParseError2> {
 
        // Parse keyword, optional polyvars and the identifier
 
        let position = self.source.pos();
 
        self.consume_keyword(b"composite")?;
 
        self.consume_whitespace(true)?;
 
        let identifier = self.consume_identifier()?;
 
        self.consume_whitespace(false)?;
 
        let poly_vars = self.consume_polymorphic_vars()?;
 
        let poly_vars = self.consume_polymorphic_vars(h)?;
 
        self.consume_whitespace(false)?;
 

	
 
        // Consume parameters
 
        let mut parameters = Vec::new();
 
        self.consume_parameters(h, &mut parameters)?;
 
        let parameters = self.consume_parameters(h)?;
 
        self.consume_whitespace(false)?;
 

	
 
        // Parse body
 
        let body = self.consume_block_statement(h)?;
 
        Ok(h.alloc_component(|this| Component { 
 
            this,
 
            variant: ComponentVariant::Composite,
 
            position,
 
            identifier,
 
            poly_vars,
 
            parameters,
 
            body
 
        }))
 
    }
 
    fn consume_primitive_definition(&mut self, h: &mut Heap) -> Result<ComponentId, ParseError2> {
 
        // Consume keyword, optional polyvars and identifier
 
        let position = self.source.pos();
 
        self.consume_keyword(b"primitive")?;
 
        self.consume_whitespace(true)?;
 
        let identifier = self.consume_identifier()?;
 
        self.consume_whitespace(false)?;
 
        let poly_vars = self.consume_polymorphic_vars()?;
 
        let poly_vars = self.consume_polymorphic_vars(h)?;
 
        self.consume_whitespace(false)?;
 

	
 
        // Consume parameters
 
        let mut parameters = Vec::new();
 
        self.consume_parameters(h, &mut parameters)?;
 
        let parameters = self.consume_parameters(h)?;
 
        self.consume_whitespace(false)?;
 

	
 
        // Consume body
 
        let body = self.consume_block_statement(h)?;
 
        Ok(h.alloc_component(|this| Component { 
 
            this,
 
            variant: ComponentVariant::Primitive,
 
            position,
 
            identifier,
 
            poly_vars,
 
            parameters,
 
            body
 
        }))
 
    }
 
    fn consume_function_definition(&mut self, h: &mut Heap) -> Result<FunctionId, ParseError2> {
 
        // Consume return type, optional polyvars and identifier
 
        let position = self.source.pos();
 
        let return_type = self.consume_type2(h, false)?;
 
        self.consume_whitespace(true)?;
 
        let identifier = self.consume_identifier()?;
 
        self.consume_whitespace(false)?;
 
        let poly_vars = self.consume_polymorphic_vars()?;
 
        let poly_vars = self.consume_polymorphic_vars(h)?;
 
        self.consume_whitespace(false)?;
 

	
 
        // Consume parameters
 
        let mut parameters = Vec::new();
 
        self.consume_parameters(h, &mut parameters)?;
 
        let parameters = self.consume_parameters(h)?;
 
        self.consume_whitespace(false)?;
 

	
 
        // Consume body
 
        let body = self.consume_block_statement(h)?;
 
        Ok(h.alloc_function(|this| Function {
 
            this,
 
            position,
 
            return_type,
 
            identifier,
 
            poly_vars,
 
            parameters,
 
            body,
 
        }))
 
    }
 
    fn has_pragma(&self) -> bool {
 
        if let Some(c) = self.source.next() {
 
            c == b'#'
 
        } else {
 
            false
 
        }
 
    }
 
    fn consume_pragma(&mut self, h: &mut Heap) -> Result<PragmaId, ParseError2> {
 
        let position = self.source.pos();
 
        let next = self.source.next();
 
        if next != Some(b'#') {
 
            return Err(self.error_at_pos("Expected pragma"));
 
        }
 
        self.source.consume();
 
        if !is_vchar(self.source.next()) {
 
            return Err(self.error_at_pos("Expected pragma"));
 
        }
 
        if self.has_string(b"version") {
 
            self.consume_string(b"version")?;
 
            self.consume_whitespace(true)?;
 
            if !self.has_integer() {
 
                return Err(self.error_at_pos("Expected integer constant"));
 
            }
 
            let version = self.consume_integer()?;
 
            debug_assert!(version >= 0);
 
            return Ok(h.alloc_pragma(|this| Pragma::Version(PragmaVersion{
 
                this, position, version: version as u64
 
            })))
 
        } else if self.has_string(b"module") {
 
            self.consume_string(b"module")?;
 
            self.consume_whitespace(true)?;
 
            if !self.has_identifier() {
 
                return Err(self.error_at_pos("Expected identifier"));
 
            }
 
            let mut value = Vec::new();
 
            let mut ident = self.consume_ident()?;
 
            value.append(&mut ident);
 
            while self.has_string(b".") {
 
                self.consume_string(b".")?;
 
                value.push(b'.');
 
                ident = self.consume_ident()?;
 
                value.append(&mut ident);
 
            }
 
            return Ok(h.alloc_pragma(|this| Pragma::Module(PragmaModule{
 
                this, position, value
 
            })));
 
        } else {
 
            return Err(self.error_at_pos("Unknown pragma"));
 
        }
 
    }
 

	
 
    fn has_import(&self) -> bool {
 
        self.has_keyword(b"import")
 
    }
 
    fn consume_import(&mut self, h: &mut Heap) -> Result<ImportId, ParseError2> {
 
        // Parse the word "import" and the name of the module
 
        let position = self.source.pos();
 
        self.consume_keyword(b"import")?;
 
        self.consume_whitespace(true)?;
 
        let mut value = Vec::new();
 
        let mut ident = self.consume_ident()?;
 
        value.append(&mut ident);
 
        let mut last_ident_start = 0;
 

	
 
        while self.has_string(b".") {
 
            self.consume_string(b".")?;
 
            value.push(b'.');
 
            ident = self.consume_ident()?;
 
            last_ident_start = value.len();
 
            value.append(&mut ident);
 
        }
 

	
 

	
 
        self.consume_whitespace(false)?;
 

	
 
        // Check for the potential aliasing or specific module imports
 
        let import = if self.has_string(b"as") {
 
            self.consume_string(b"as")?;
 
            self.consume_whitespace(true)?;
 
            let alias = self.consume_ident()?;
 

	
 
            h.alloc_import(|this| Import::Module(ImportModule{
 
                this,
 
                position,
 
                module_name: value,
 
                alias,
 
                module_id: None,
 
            }))
 
        } else if self.has_string(b"::") {
 
            self.consume_string(b"::")?;
 
            self.consume_whitespace(false)?;
 

	
 
            if let Some(b'{') = self.source.next() {
 
                // Import specific symbols, optionally with an alias
 
                self.source.consume();
 
                self.consume_whitespace(false)?;
 

	
 
                let mut symbols = Vec::new();
 
                let mut next = self.source.next();
 

	
 
                while next.is_some() {
 
                    let char = next.unwrap();
 
                    if char == b'}' {
 
                        break;
 
                    }
 

	
 
                    let symbol_position = self.source.pos();
 
                    let symbol_name = self.consume_ident()?;
 
                    self.consume_whitespace(false)?;
 
                    if self.has_string(b"as") {
 
                        // Symbol has an alias
 
                        self.consume_string(b"as")?;
 
                        self.consume_whitespace(true)?;
 
                        let symbol_alias = self.consume_ident()?;
 

	
 
                        symbols.push(AliasedSymbol{
 
                            position: symbol_position,
 
                            name: symbol_name,
 
                            alias: symbol_alias,
 
                            definition_id: None,
 
                        });
 
                    } else {
 
                        // Symbol does not have an alias
 
                        symbols.push(AliasedSymbol{
 
                            position: symbol_position,
 
                            name: symbol_name.clone(),
 
                            alias: symbol_name,
 
                            definition_id: None,
 
                        });
 
                    }
 

	
 
                    // A comma indicates that we may have another symbol coming
 
                    // up (not necessary), but if not present then we expect the
 
                    // end of the symbol list
 
                    self.consume_whitespace(false)?;
 

	
 
                    next = self.source.next();
 
                    if let Some(b',') = next {
 
                        self.source.consume();
 
                        self.consume_whitespace(false)?;
 
                        next = self.source.next();
 
            let next = self.source.next();
 
            if Some(b'{') == next {
 
                let symbols = match self.consume_comma_separated(
 
                    h, b'{', b'}', "Expected end of import list",
 
                    |lexer, heap| {
 
                        // Symbol name
 
                        let position = lexer.source.pos();
 
                        let name = lexer.consume_ident()?;
 
                        lexer.consume_whitespace(false)?;
 

	
 
                        // Symbol alias
 
                        if lexer.has_string(b"as") {
 
                            // With alias
 
                            lexer.consume_string(b"as")?;
 
                            lexer.consume_whitespace(true)?;
 
                            let alias = lexer.consume_ident()?;
 

	
 
                            Ok(AliasedSymbol{
 
                                position,
 
                                name,
 
                                alias,
 
                                definition_id: None
 
                            })
 
                        } else {
 
                        break;
 
                    }
 
                            // Without alias
 
                            Ok(AliasedSymbol{
 
                                position,
 
                                name: name.clone(),
 
                                alias: name,
 
                                definition_id: None
 
                            })
 
                        }
 

	
 
                if let Some(b'}') = next {
 
                    // We are fine, push the imported symbols
 
                    self.source.consume();
 
                    if symbols.is_empty() {
 
                        return Err(ParseError2::new_error(self.source, position, "empty symbol import list"));
 
                    }
 
                )? {
 
                    Some(symbols) => symbols,
 
                    None => unreachable!(), // because we checked for opening '{'
 
                };
 

	
 
                h.alloc_import(|this| Import::Symbols(ImportSymbols{
 
                    this,
 
                    position,
 
                    module_name: value,
 
                    module_id: None,
 
                    symbols,
 
                }))
 
                } else {
 
                    return Err(self.error_at_pos("Expected '}'"));
 
                }
 
            } else if let Some(b'*') = self.source.next() {
 
                // Import all symbols without alias
 
            } else if Some(b'*') == next {
 
                self.source.consume();
 
                h.alloc_import(|this| Import::Symbols(ImportSymbols{
 
                    this,
 
                    position,
 
                    module_name: value,
 
                    module_id: None,
 
                    symbols: Vec::new()
 
                }))
 
            } else {
 
                return Err(self.error_at_pos("Expected '*' or '{'"));
 
            }
 
        } else {
 
            // No explicit alias or subimports, so implicit alias
 
            let alias = Vec::from(&value[last_ident_start..]);
 
            h.alloc_import(|this| Import::Module(ImportModule{
 
                this,
 
                position,
 
                module_name: value,
 
                alias,
 
                module_id: None,
 
            }))
 
        };
 

	
 
        self.consume_whitespace(false)?;
 
        self.consume_string(b";")?;
 
        Ok(import)
 
    }
 
    pub fn consume_protocol_description(&mut self, h: &mut Heap) -> Result<RootId, ParseError2> {
 
        let position = self.source.pos();
 
        let mut pragmas = Vec::new();
 
        let mut imports = Vec::new();
 
        let mut definitions = Vec::new();
 
        self.consume_whitespace(false)?;
 
        while self.has_pragma() {
 
            let pragma = self.consume_pragma(h)?;
 
            pragmas.push(pragma);
 
            self.consume_whitespace(false)?;
 
        }
 
        while self.has_import() {
 
            let import = self.consume_import(h)?;
 
            imports.push(import);
 
            self.consume_whitespace(false)?;
 
        }
 
        while self.has_symbol_definition() {
 
            let def = self.consume_symbol_definition(h)?;
 
            definitions.push(def);
 
            self.consume_whitespace(false)?;
 
        }
 
        // end of file
 
        if !self.source.is_eof() {
 
            return Err(self.error_at_pos("Expected end of file"));
 
        }
 
        Ok(h.alloc_protocol_description(|this| Root {
 
            this,
 
            position,
 
            pragmas,
 
            imports,
 
            definitions,
 
        }))
 
    }
 
}
src/protocol/mod.rs
Show inline comments
 
mod arena;
 
// mod ast;
 
mod eval;
 
pub(crate) mod inputsource;
 
// mod lexer;
 
mod parser;
 
#[cfg(test)] mod tests;
 

	
 
// TODO: Remove when not benchmarking
 
pub(crate) mod ast;
 
pub(crate) mod ast_printer;
 
pub(crate) mod lexer;
 

	
 
lazy_static::lazy_static! {
 
    /// Conveniently-provided protocol description initialized with a zero-length PDL string.
 
    /// Exposed to minimize repeated initializations of this common protocol description.
 
    pub static ref TRIVIAL_PD: std::sync::Arc<ProtocolDescription> = {
 
        std::sync::Arc::new(ProtocolDescription::parse(b"").unwrap())
 
    };
 
}
 

	
 
use crate::common::*;
 
use crate::protocol::ast::*;
 
use crate::protocol::eval::*;
 
use crate::protocol::inputsource::*;
 
use crate::protocol::parser::*;
 

	
 
/// Description of a protocol object, used to configure new connectors.
 
/// (De)serializable.
 
#[derive(serde::Serialize, serde::Deserialize)]
 
#[repr(C)]
 
pub struct ProtocolDescription {
 
    heap: Heap,
 
    source: InputSource,
 
    root: RootId,
 
}
 
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 
pub(crate) struct ComponentState {
 
    prompt: Prompt,
 
}
 
pub(crate) enum EvalContext<'a> {
 
    Nonsync(&'a mut NonsyncProtoContext<'a>),
 
    Sync(&'a mut SyncProtoContext<'a>),
 
    // None,
 
}
 
//////////////////////////////////////////////
 

	
 
impl std::fmt::Debug for ProtocolDescription {
 
    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 
        write!(f, "(An opaque protocol description)")
 
    }
 
}
 
impl ProtocolDescription {
 
    pub fn parse(buffer: &[u8]) -> Result<Self, String> {
 
        // TODO: @fixme, keep code compilable, but needs support for multiple
 
        //  input files.
 
        let source = InputSource::from_buffer(buffer).unwrap();
 
        let mut parser = Parser::new();
 
        parser.feed(source).expect("failed to parse source");
 
        match parser.parse() {
 
            Ok(root) => {
 
                return Ok(ProtocolDescription { heap: parser.heap, source: parser.modules[0].source.clone(), root });
 
            }
 
            Err(err) => {
 
                println!("ERROR:\n{}", err);
 
                Err(format!("{}", err))
 
            }
 
        }
 
    }
 
    pub(crate) fn component_polarities(
 
        &self,
 
        identifier: &[u8],
 
    ) -> Result<Vec<Polarity>, AddComponentError> {
 
        use AddComponentError::*;
 
        let h = &self.heap;
 
        let root = &h[self.root];
 
        let def = root.get_definition_ident(h, identifier);
 
        if def.is_none() {
 
            return Err(NoSuchComponent);
 
        }
 
        let def = &h[def.unwrap()];
 
        if !def.is_component() {
 
            return Err(NoSuchComponent);
 
        }
 
        for &param in def.parameters().iter() {
 
            let param = &h[param];
 
            let parser_type = &h[param.parser_type];
 

	
 
            match parser_type.variant {
 
                ParserTypeVariant::Input(_) | ParserTypeVariant::Output(_) => continue,
 
                _ => {
 
                    return Err(NonPortTypeParameters);
 
                }
 
            }
 
        }
 
        let mut result = Vec::new();
 
        for &param in def.parameters().iter() {
 
            let param = &h[param];
 
            let parser_type = &h[param.parser_type];
 

	
 
            if let ParserTypeVariant::Input(_) = parser_type.variant {
 
                result.push(Polarity::Getter)
 
            } else if let ParserTypeVariant::Output(_) = parser_type.variant {
 
                result.push(Polarity::Putter)
 
            } else {
 
                unreachable!()
 
            }
 
        }
 
        Ok(result)
 
    }
 
    // expects port polarities to be correct
 
    pub(crate) fn new_component(&self, identifier: &[u8], ports: &[PortId]) -> ComponentState {
 
        let mut args = Vec::new();
 
        for (&x, y) in ports.iter().zip(self.component_polarities(identifier).unwrap()) {
 
            match y {
 
                Polarity::Getter => args.push(Value::Input(InputValue(x))),
 
                Polarity::Putter => args.push(Value::Output(OutputValue(x))),
 
            }
 
        }
 
        let h = &self.heap;
 
        let root = &h[self.root];
 
        let def = root.get_definition_ident(h, identifier).unwrap();
 
        ComponentState { prompt: Prompt::new(h, def, &args) }
 
    }
 
}
 
impl ComponentState {
 
    pub(crate) fn nonsync_run<'a: 'b, 'b>(
 
        &'a mut self,
 
        context: &'b mut NonsyncProtoContext<'b>,
 
        pd: &'a ProtocolDescription,
 
    ) -> NonsyncBlocker {
 
        let mut context = EvalContext::Nonsync(context);
 
        loop {
 
            let result = self.prompt.step(&pd.heap, &mut context);
 
            match result {
 
                // In component definitions, there are no return statements
 
                Ok(_) => unreachable!(),
 
                Err(cont) => match cont {
 
                    EvalContinuation::Stepping => continue,
 
                    EvalContinuation::Inconsistent => return NonsyncBlocker::Inconsistent,
 
                    EvalContinuation::Terminal => return NonsyncBlocker::ComponentExit,
 
                    EvalContinuation::SyncBlockStart => return NonsyncBlocker::SyncBlockStart,
 
                    // Not possible to end sync block if never entered one
 
                    EvalContinuation::SyncBlockEnd => unreachable!(),
 
                    EvalContinuation::NewComponent(definition_id, args) => {
 
                        // Look up definition (TODO for now, assume it is a definition)
 
                        let h = &pd.heap;
 
                        let init_state = ComponentState { prompt: Prompt::new(h, definition_id, &args) };
 
                        context.new_component(&args, init_state);
 
                        // Continue stepping
 
                        continue;
 
                    }
 
                    // Outside synchronous blocks, no fires/get/put happens
 
                    EvalContinuation::BlockFires(_) => unreachable!(),
 
                    EvalContinuation::BlockGet(_) => unreachable!(),
 
                    EvalContinuation::Put(_, _) => unreachable!(),
 
                },
 
            }
 
        }
 
    }
 

	
 
    pub(crate) fn sync_run<'a: 'b, 'b>(
 
        &'a mut self,
 
        context: &'b mut SyncProtoContext<'b>,
 
        pd: &'a ProtocolDescription,
 
    ) -> SyncBlocker {
 
        let mut context = EvalContext::Sync(context);
 
        loop {
 
            let result = self.prompt.step(&pd.heap, &mut context);
 
            match result {
 
                // Inside synchronous blocks, there are no return statements
 
                Ok(_) => unreachable!(),
 
                Err(cont) => match cont {
 
                    EvalContinuation::Stepping => continue,
 
                    EvalContinuation::Inconsistent => return SyncBlocker::Inconsistent,
 
                    // First need to exit synchronous block before definition may end
 
                    EvalContinuation::Terminal => unreachable!(),
 
                    // No nested synchronous blocks
 
                    EvalContinuation::SyncBlockStart => unreachable!(),
 
                    EvalContinuation::SyncBlockEnd => return SyncBlocker::SyncBlockEnd,
 
                    // Not possible to create component in sync block
 
                    EvalContinuation::NewComponent(_, _) => unreachable!(),
 
                    EvalContinuation::BlockFires(port) => match port {
 
                        Value::Output(OutputValue(port)) => {
 
                            return SyncBlocker::CouldntCheckFiring(port);
 
                        }
 
                        Value::Input(InputValue(port)) => {
 
                            return SyncBlocker::CouldntCheckFiring(port);
 
                        }
 
                        _ => unreachable!(),
 
                    },
 
                    EvalContinuation::BlockGet(port) => match port {
 
                        Value::Output(OutputValue(port)) => {
 
                            return SyncBlocker::CouldntReadMsg(port);
 
                        }
 
                        Value::Input(InputValue(port)) => {
 
                            return SyncBlocker::CouldntReadMsg(port);
 
                        }
 
                        _ => unreachable!(),
 
                    },
 
                    EvalContinuation::Put(port, message) => {
 
                        let value;
 
                        match port {
 
                            Value::Output(OutputValue(port_value)) => {
 
                                value = port_value;
 
                            }
 
                            Value::Input(InputValue(port_value)) => {
 
                                value = port_value;
 
                            }
 
                            _ => unreachable!(),
 
                        }
 
                        let payload;
 
                        match message {
 
                            Value::Message(MessageValue(None)) => {
 
                                // Putting a null message is inconsistent
 
                                return SyncBlocker::Inconsistent;
 
                            }
 
                            Value::Message(MessageValue(Some(buffer))) => {
 
                                // Create a copy of the payload
 
                                payload = buffer;
 
                            }
 
                            _ => unreachable!(),
 
                        }
 
                        return SyncBlocker::PutMsg(value, payload);
 
                    }
 
                },
 
            }
 
        }
 
    }
 
}
 
impl EvalContext<'_> {
 
    // fn random(&mut self) -> LongValue {
 
    //     match self {
 
    //         // EvalContext::None => unreachable!(),
 
    //         EvalContext::Nonsync(_context) => todo!(),
 
    //         EvalContext::Sync(_) => unreachable!(),
 
    //     }
 
    // }
 
    fn new_component(&mut self, args: &[Value], init_state: ComponentState) -> () {
 
        match self {
 
            // EvalContext::None => unreachable!(),
 
            EvalContext::Nonsync(context) => {
 
                let mut moved_ports = HashSet::new();
 
                for arg in args.iter() {
 
                    match arg {
 
                        Value::Output(OutputValue(port)) => {
 
                            moved_ports.insert(*port);
 
                        }
 
                        Value::Input(InputValue(port)) => {
 
                            moved_ports.insert(*port);
 
                        }
 
                        _ => {}
 
                    }
 
                }
 
                context.new_component(moved_ports, init_state)
 
            }
 
            EvalContext::Sync(_) => unreachable!(),
 
        }
 
    }
 
    fn new_channel(&mut self) -> [Value; 2] {
 
        match self {
 
            // EvalContext::None => unreachable!(),
 
            EvalContext::Nonsync(context) => {
 
                let [from, to] = context.new_port_pair();
 
                let from = Value::Output(OutputValue(from));
 
                let to = Value::Input(InputValue(to));
 
                return [from, to];
 
            }
 
            EvalContext::Sync(_) => unreachable!(),
 
        }
 
    }
 
    fn fires(&mut self, port: Value) -> Option<Value> {
 
        match self {
 
            // EvalContext::None => unreachable!(),
 
            EvalContext::Nonsync(_) => unreachable!(),
 
            EvalContext::Sync(context) => match port {
 
                Value::Output(OutputValue(port)) => context.is_firing(port).map(Value::from),
 
                Value::Input(InputValue(port)) => context.is_firing(port).map(Value::from),
 
                _ => unreachable!(),
 
            },
 
        }
 
    }
 
    fn get(&mut self, port: Value) -> Option<Value> {
 
        match self {
 
            // EvalContext::None => unreachable!(),
 
            EvalContext::Nonsync(_) => unreachable!(),
 
            EvalContext::Sync(context) => match port {
 
                Value::Output(OutputValue(port)) => {
 
                    context.read_msg(port).map(Value::receive_message)
 
                }
 
                Value::Input(InputValue(port)) => {
 
                    context.read_msg(port).map(Value::receive_message)
 
                }
 
                _ => unreachable!(),
 
            },
 
        }
 
    }
 
    fn did_put(&mut self, port: Value) -> bool {
 
        match self {
 
            EvalContext::Nonsync(_) => unreachable!("did_put in nonsync context"),
 
            EvalContext::Sync(context) => match port {
 
                Value::Output(OutputValue(port)) => {
 
                    context.did_put_or_get(port)
 
                },
 
                Value::Input(_) => unreachable!("did_put on input port"),
 
                _ => unreachable!("did_put on non-port value")
 
            }
 
        }
 
    }
 
}
src/protocol/parser/depth_visitor.rs
Show inline comments
 
use crate::protocol::ast::*;
 
use crate::protocol::inputsource::*;
 

	
 
// The following indirection is needed due to a bug in the cbindgen tool.
 
type Unit = ();
 
pub(crate) type VisitorError = (InputPosition, String); // TODO: Revise when multi-file compiling is in place
 
pub(crate) type VisitorResult = Result<Unit, VisitorError>;
 

	
 
pub(crate) trait Visitor: Sized {
 
    fn visit_protocol_description(&mut self, h: &mut Heap, pd: RootId) -> VisitorResult {
 
        recursive_protocol_description(self, h, pd)
 
    }
 
    fn visit_pragma(&mut self, _h: &mut Heap, _pragma: PragmaId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_import(&mut self, _h: &mut Heap, _import: ImportId) -> VisitorResult {
 
        Ok(())
 
    }
 

	
 
    fn visit_symbol_definition(&mut self, h: &mut Heap, def: DefinitionId) -> VisitorResult {
 
        recursive_symbol_definition(self, h, def)
 
    }
 
    fn visit_struct_definition(&mut self, _h: &mut Heap, _def: StructId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_enum_definition(&mut self, _h: &mut Heap, _def: EnumId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_component_definition(&mut self, h: &mut Heap, def: ComponentId) -> VisitorResult {
 
        recursive_component_definition(self, h, def)
 
    }
 
    fn visit_composite_definition(&mut self, h: &mut Heap, def: ComponentId) -> VisitorResult {
 
        recursive_composite_definition(self, h, def)
 
    }
 
    fn visit_primitive_definition(&mut self, h: &mut Heap, def: ComponentId) -> VisitorResult {
 
        recursive_primitive_definition(self, h, def)
 
    }
 
    fn visit_function_definition(&mut self, h: &mut Heap, def: FunctionId) -> VisitorResult {
 
        recursive_function_definition(self, h, def)
 
    }
 

	
 
    fn visit_variable_declaration(&mut self, h: &mut Heap, decl: VariableId) -> VisitorResult {
 
        recursive_variable_declaration(self, h, decl)
 
    }
 
    fn visit_parameter_declaration(&mut self, _h: &mut Heap, _decl: ParameterId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_local_declaration(&mut self, _h: &mut Heap, _decl: LocalId) -> VisitorResult {
 
        Ok(())
 
    }
 

	
 
    fn visit_statement(&mut self, h: &mut Heap, stmt: StatementId) -> VisitorResult {
 
        recursive_statement(self, h, stmt)
 
    }
 
    fn visit_local_statement(&mut self, h: &mut Heap, stmt: LocalStatementId) -> VisitorResult {
 
        recursive_local_statement(self, h, stmt)
 
    }
 
    fn visit_memory_statement(&mut self, h: &mut Heap, stmt: MemoryStatementId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_channel_statement(
 
        &mut self,
 
        _h: &mut Heap,
 
        _stmt: ChannelStatementId,
 
    ) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_block_statement(&mut self, h: &mut Heap, stmt: BlockStatementId) -> VisitorResult {
 
        recursive_block_statement(self, h, stmt)
 
    }
 
    fn visit_labeled_statement(&mut self, h: &mut Heap, stmt: LabeledStatementId) -> VisitorResult {
 
        recursive_labeled_statement(self, h, stmt)
 
    }
 
    fn visit_skip_statement(&mut self, _h: &mut Heap, _stmt: SkipStatementId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_if_statement(&mut self, h: &mut Heap, stmt: IfStatementId) -> VisitorResult {
 
        recursive_if_statement(self, h, stmt)
 
    }
 
    fn visit_end_if_statement(&mut self, _h: &mut Heap, _stmt: EndIfStatementId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_while_statement(&mut self, h: &mut Heap, stmt: WhileStatementId) -> VisitorResult {
 
        recursive_while_statement(self, h, stmt)
 
    }
 
    fn visit_end_while_statement(&mut self, _h: &mut Heap, _stmt: EndWhileStatementId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_break_statement(&mut self, _h: &mut Heap, _stmt: BreakStatementId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_continue_statement(
 
        &mut self,
 
        _h: &mut Heap,
 
        _stmt: ContinueStatementId,
 
    ) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_synchronous_statement(
 
        &mut self,
 
        h: &mut Heap,
 
        stmt: SynchronousStatementId,
 
    ) -> VisitorResult {
 
        recursive_synchronous_statement(self, h, stmt)
 
    }
 
    fn visit_end_synchronous_statement(&mut self, _h: &mut Heap, _stmt: EndSynchronousStatementId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_return_statement(&mut self, h: &mut Heap, stmt: ReturnStatementId) -> VisitorResult {
 
        recursive_return_statement(self, h, stmt)
 
    }
 
    fn visit_assert_statement(&mut self, h: &mut Heap, stmt: AssertStatementId) -> VisitorResult {
 
        recursive_assert_statement(self, h, stmt)
 
    }
 
    fn visit_goto_statement(&mut self, _h: &mut Heap, _stmt: GotoStatementId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_new_statement(&mut self, h: &mut Heap, stmt: NewStatementId) -> VisitorResult {
 
        recursive_new_statement(self, h, stmt)
 
    }
 
    fn visit_expression_statement(
 
        &mut self,
 
        h: &mut Heap,
 
        stmt: ExpressionStatementId,
 
    ) -> VisitorResult {
 
        recursive_expression_statement(self, h, stmt)
 
    }
 

	
 
    fn visit_expression(&mut self, h: &mut Heap, expr: ExpressionId) -> VisitorResult {
 
        recursive_expression(self, h, expr)
 
    }
 
    fn visit_assignment_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: AssignmentExpressionId,
 
    ) -> VisitorResult {
 
        recursive_assignment_expression(self, h, expr)
 
    }
 
    fn visit_conditional_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: ConditionalExpressionId,
 
    ) -> VisitorResult {
 
        recursive_conditional_expression(self, h, expr)
 
    }
 
    fn visit_binary_expression(&mut self, h: &mut Heap, expr: BinaryExpressionId) -> VisitorResult {
 
        recursive_binary_expression(self, h, expr)
 
    }
 
    fn visit_unary_expression(&mut self, h: &mut Heap, expr: UnaryExpressionId) -> VisitorResult {
 
        recursive_unary_expression(self, h, expr)
 
    }
 
    fn visit_indexing_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: IndexingExpressionId,
 
    ) -> VisitorResult {
 
        recursive_indexing_expression(self, h, expr)
 
    }
 
    fn visit_slicing_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: SlicingExpressionId,
 
    ) -> VisitorResult {
 
        recursive_slicing_expression(self, h, expr)
 
    }
 
    fn visit_select_expression(&mut self, h: &mut Heap, expr: SelectExpressionId) -> VisitorResult {
 
        recursive_select_expression(self, h, expr)
 
    }
 
    fn visit_array_expression(&mut self, h: &mut Heap, expr: ArrayExpressionId) -> VisitorResult {
 
        recursive_array_expression(self, h, expr)
 
    }
 
    fn visit_call_expression(&mut self, h: &mut Heap, expr: CallExpressionId) -> VisitorResult {
 
        recursive_call_expression(self, h, expr)
 
    }
 
    fn visit_constant_expression(
 
        &mut self,
 
        _h: &mut Heap,
 
        _expr: ConstantExpressionId,
 
        _expr: LiteralExpressionId,
 
    ) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_variable_expression(
 
        &mut self,
 
        _h: &mut Heap,
 
        _expr: VariableExpressionId,
 
    ) -> VisitorResult {
 
        Ok(())
 
    }
 
}
 

	
 
// Bubble-up helpers
 
fn recursive_parameter_as_variable<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    param: ParameterId,
 
) -> VisitorResult {
 
    this.visit_variable_declaration(h, param.upcast())
 
}
 

	
 
fn recursive_local_as_variable<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    local: LocalId,
 
) -> VisitorResult {
 
    this.visit_variable_declaration(h, local.upcast())
 
}
 

	
 
fn recursive_call_expression_as_expression<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    call: CallExpressionId,
 
) -> VisitorResult {
 
    this.visit_expression(h, call.upcast())
 
}
 

	
 
// Recursive procedures
 
fn recursive_protocol_description<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    pd: RootId,
 
) -> VisitorResult {
 
    for &pragma in h[pd].pragmas.clone().iter() {
 
        this.visit_pragma(h, pragma)?;
 
    }
 
    for &import in h[pd].imports.clone().iter() {
 
        this.visit_import(h, import)?;
 
    }
 
    for &def in h[pd].definitions.clone().iter() {
 
        this.visit_symbol_definition(h, def)?;
 
    }
 
    Ok(())
 
}
 

	
 
fn recursive_symbol_definition<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    def: DefinitionId,
 
) -> VisitorResult {
 
    // We clone the definition in case it is modified
 
    // TODO: Fix me
 
    match h[def].clone() {
 
        Definition::Struct(def) => this.visit_struct_definition(h, def.this),
 
        Definition::Enum(def) => this.visit_enum_definition(h, def.this),
 
        Definition::Component(cdef) => this.visit_component_definition(h, cdef.this),
 
        Definition::Function(fdef) => this.visit_function_definition(h, fdef.this),
 
    }
 
}
 

	
 
fn recursive_component_definition<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    def: ComponentId,
 
) -> VisitorResult {
 
    let component_variant = h[def].variant;
 
    match component_variant {
 
        ComponentVariant::Primitive => this.visit_primitive_definition(h, def),
 
        ComponentVariant::Composite => this.visit_composite_definition(h, def),
 
    }
 
}
 

	
 
fn recursive_composite_definition<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    def: ComponentId,
 
) -> VisitorResult {
 
    for &param in h[def].parameters.clone().iter() {
 
        recursive_parameter_as_variable(this, h, param)?;
 
    }
 
    this.visit_statement(h, h[def].body)
 
}
 

	
 
fn recursive_primitive_definition<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    def: ComponentId,
 
) -> VisitorResult {
 
    for &param in h[def].parameters.clone().iter() {
 
        recursive_parameter_as_variable(this, h, param)?;
 
    }
 
    this.visit_statement(h, h[def].body)
 
}
 

	
 
fn recursive_function_definition<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    def: FunctionId,
 
) -> VisitorResult {
 
    for &param in h[def].parameters.clone().iter() {
 
        recursive_parameter_as_variable(this, h, param)?;
 
    }
 
    this.visit_statement(h, h[def].body)
 
}
 

	
 
fn recursive_variable_declaration<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    decl: VariableId,
 
) -> VisitorResult {
 
    match h[decl].clone() {
 
        Variable::Parameter(decl) => this.visit_parameter_declaration(h, decl.this),
 
        Variable::Local(decl) => this.visit_local_declaration(h, decl.this),
 
    }
 
}
 

	
 
fn recursive_statement<T: Visitor>(this: &mut T, h: &mut Heap, stmt: StatementId) -> VisitorResult {
 
    match h[stmt].clone() {
 
        Statement::Block(stmt) => this.visit_block_statement(h, stmt.this),
 
        Statement::Local(stmt) => this.visit_local_statement(h, stmt.this()),
 
        Statement::Skip(stmt) => this.visit_skip_statement(h, stmt.this),
 
        Statement::Labeled(stmt) => this.visit_labeled_statement(h, stmt.this),
 
        Statement::If(stmt) => this.visit_if_statement(h, stmt.this),
 
        Statement::While(stmt) => this.visit_while_statement(h, stmt.this),
 
        Statement::Break(stmt) => this.visit_break_statement(h, stmt.this),
 
        Statement::Continue(stmt) => this.visit_continue_statement(h, stmt.this),
 
        Statement::Synchronous(stmt) => this.visit_synchronous_statement(h, stmt.this),
 
        Statement::Return(stmt) => this.visit_return_statement(h, stmt.this),
 
        Statement::Assert(stmt) => this.visit_assert_statement(h, stmt.this),
 
        Statement::Goto(stmt) => this.visit_goto_statement(h, stmt.this),
 
        Statement::New(stmt) => this.visit_new_statement(h, stmt.this),
 
        Statement::Expression(stmt) => this.visit_expression_statement(h, stmt.this),
 
        Statement::EndSynchronous(stmt) => this.visit_end_synchronous_statement(h, stmt.this),
 
        Statement::EndWhile(stmt) => this.visit_end_while_statement(h, stmt.this),
 
        Statement::EndIf(stmt) => this.visit_end_if_statement(h, stmt.this),
 
    }
 
}
 

	
 
fn recursive_block_statement<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    block: BlockStatementId,
 
) -> VisitorResult {
 
    for &local in h[block].locals.clone().iter() {
 
        recursive_local_as_variable(this, h, local)?;
 
    }
 
    for &stmt in h[block].statements.clone().iter() {
 
        this.visit_statement(h, stmt)?;
 
    }
 
    Ok(())
 
}
 

	
 
fn recursive_local_statement<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    stmt: LocalStatementId,
 
) -> VisitorResult {
 
    match h[stmt].clone() {
 
        LocalStatement::Channel(stmt) => this.visit_channel_statement(h, stmt.this),
 
        LocalStatement::Memory(stmt) => this.visit_memory_statement(h, stmt.this),
 
    }
 
}
 

	
 
fn recursive_labeled_statement<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    stmt: LabeledStatementId,
 
) -> VisitorResult {
 
    this.visit_statement(h, h[stmt].body)
 
}
 

	
 
fn recursive_if_statement<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    stmt: IfStatementId,
 
) -> VisitorResult {
 
    this.visit_expression(h, h[stmt].test)?;
 
    this.visit_statement(h, h[stmt].true_body)?;
 
    this.visit_statement(h, h[stmt].false_body)
 
}
 

	
 
fn recursive_while_statement<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    stmt: WhileStatementId,
 
) -> VisitorResult {
 
    this.visit_expression(h, h[stmt].test)?;
 
    this.visit_statement(h, h[stmt].body)
 
}
 

	
 
fn recursive_synchronous_statement<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    stmt: SynchronousStatementId,
 
) -> VisitorResult {
 
    // TODO: Check where this was used for
 
    // for &param in h[stmt].parameters.clone().iter() {
 
    //     recursive_parameter_as_variable(this, h, param)?;
 
    // }
 
    this.visit_statement(h, h[stmt].body)
 
}
 

	
 
fn recursive_return_statement<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    stmt: ReturnStatementId,
 
) -> VisitorResult {
 
    this.visit_expression(h, h[stmt].expression)
 
}
 

	
 
fn recursive_assert_statement<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    stmt: AssertStatementId,
 
) -> VisitorResult {
 
    this.visit_expression(h, h[stmt].expression)
 
}
 

	
 
fn recursive_new_statement<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    stmt: NewStatementId,
 
) -> VisitorResult {
 
    recursive_call_expression_as_expression(this, h, h[stmt].expression)
 
}
 

	
 
fn recursive_expression_statement<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    stmt: ExpressionStatementId,
 
) -> VisitorResult {
 
    this.visit_expression(h, h[stmt].expression)
 
}
 

	
 
fn recursive_expression<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    expr: ExpressionId,
 
) -> VisitorResult {
 
    match h[expr].clone() {
 
        Expression::Assignment(expr) => this.visit_assignment_expression(h, expr.this),
 
        Expression::Conditional(expr) => this.visit_conditional_expression(h, expr.this),
 
        Expression::Binary(expr) => this.visit_binary_expression(h, expr.this),
 
        Expression::Unary(expr) => this.visit_unary_expression(h, expr.this),
 
        Expression::Indexing(expr) => this.visit_indexing_expression(h, expr.this),
 
        Expression::Slicing(expr) => this.visit_slicing_expression(h, expr.this),
 
        Expression::Select(expr) => this.visit_select_expression(h, expr.this),
 
        Expression::Array(expr) => this.visit_array_expression(h, expr.this),
 
        Expression::Constant(expr) => this.visit_constant_expression(h, expr.this),
 
        Expression::Literal(expr) => this.visit_constant_expression(h, expr.this),
 
        Expression::Call(expr) => this.visit_call_expression(h, expr.this),
 
        Expression::Variable(expr) => this.visit_variable_expression(h, expr.this),
 
    }
 
}
 

	
 
fn recursive_assignment_expression<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    expr: AssignmentExpressionId,
 
) -> VisitorResult {
 
    this.visit_expression(h, h[expr].left)?;
 
    this.visit_expression(h, h[expr].right)
 
}
 

	
 
fn recursive_conditional_expression<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    expr: ConditionalExpressionId,
 
) -> VisitorResult {
 
    this.visit_expression(h, h[expr].test)?;
 
    this.visit_expression(h, h[expr].true_expression)?;
 
    this.visit_expression(h, h[expr].false_expression)
 
}
 

	
 
fn recursive_binary_expression<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    expr: BinaryExpressionId,
 
) -> VisitorResult {
 
    this.visit_expression(h, h[expr].left)?;
 
    this.visit_expression(h, h[expr].right)
 
}
 

	
 
fn recursive_unary_expression<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    expr: UnaryExpressionId,
 
) -> VisitorResult {
 
    this.visit_expression(h, h[expr].expression)
 
}
 

	
 
fn recursive_indexing_expression<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    expr: IndexingExpressionId,
 
) -> VisitorResult {
 
    this.visit_expression(h, h[expr].subject)?;
 
    this.visit_expression(h, h[expr].index)
 
}
 

	
 
fn recursive_slicing_expression<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    expr: SlicingExpressionId,
 
) -> VisitorResult {
 
    this.visit_expression(h, h[expr].subject)?;
 
    this.visit_expression(h, h[expr].from_index)?;
 
    this.visit_expression(h, h[expr].to_index)
 
}
 

	
 
fn recursive_select_expression<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    expr: SelectExpressionId,
 
) -> VisitorResult {
 
    this.visit_expression(h, h[expr].subject)
 
}
 

	
 
fn recursive_array_expression<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    expr: ArrayExpressionId,
 
) -> VisitorResult {
 
    for &expr in h[expr].elements.clone().iter() {
 
        this.visit_expression(h, expr)?;
 
    }
 
    Ok(())
 
}
 

	
 
fn recursive_call_expression<T: Visitor>(
 
    this: &mut T,
 
    h: &mut Heap,
 
    expr: CallExpressionId,
 
) -> VisitorResult {
 
    for &expr in h[expr].arguments.clone().iter() {
 
        this.visit_expression(h, expr)?;
 
    }
 
    Ok(())
 
}
 

	
 
// ====================
 
// Grammar Rules
 
// ====================
 

	
 
pub(crate) struct NestedSynchronousStatements {
 
    illegal: bool,
 
}
 

	
 
impl NestedSynchronousStatements {
 
    pub(crate) fn new() -> Self {
 
        NestedSynchronousStatements { illegal: false }
 
    }
 
}
 

	
 
impl Visitor for NestedSynchronousStatements {
 
    fn visit_composite_definition(&mut self, h: &mut Heap, def: ComponentId) -> VisitorResult {
 
        assert!(!self.illegal);
 
        self.illegal = true;
 
        recursive_composite_definition(self, h, def)?;
 
        self.illegal = false;
 
        Ok(())
 
    }
 
    fn visit_function_definition(&mut self, h: &mut Heap, def: FunctionId) -> VisitorResult {
 
        assert!(!self.illegal);
 
        self.illegal = true;
 
        recursive_function_definition(self, h, def)?;
 
        self.illegal = false;
 
        Ok(())
 
    }
 
    fn visit_synchronous_statement(
 
        &mut self,
 
        h: &mut Heap,
 
        stmt: SynchronousStatementId,
 
    ) -> VisitorResult {
 
        if self.illegal {
 
            return Err((
 
                h[stmt].position(),
 
                "Illegal nested synchronous statement".to_string(),
 
            ));
 
        }
 
        self.illegal = true;
 
        recursive_synchronous_statement(self, h, stmt)?;
 
        self.illegal = false;
 
        Ok(())
 
    }
 
    fn visit_expression(&mut self, _h: &mut Heap, _expr: ExpressionId) -> VisitorResult {
 
        Ok(())
 
    }
 
}
 

	
 
pub(crate) struct ChannelStatementOccurrences {
 
    illegal: bool,
 
}
 

	
 
impl ChannelStatementOccurrences {
 
    pub(crate) fn new() -> Self {
 
        ChannelStatementOccurrences { illegal: false }
 
    }
 
}
 

	
 
impl Visitor for ChannelStatementOccurrences {
 
    fn visit_primitive_definition(&mut self, h: &mut Heap, def: ComponentId) -> VisitorResult {
 
        assert!(!self.illegal);
 
        self.illegal = true;
 
        recursive_primitive_definition(self, h, def)?;
 
        self.illegal = false;
 
        Ok(())
 
    }
 
    fn visit_function_definition(&mut self, h: &mut Heap, def: FunctionId) -> VisitorResult {
 
        assert!(!self.illegal);
 
        self.illegal = true;
 
        recursive_function_definition(self, h, def)?;
 
        self.illegal = false;
 
        Ok(())
 
    }
 
    fn visit_channel_statement(&mut self, h: &mut Heap, stmt: ChannelStatementId) -> VisitorResult {
 
        if self.illegal {
 
            return Err((h[stmt].position(), "Illegal channel declaration".to_string()));
 
        }
 
        Ok(())
 
    }
 
    fn visit_expression(&mut self, _h: &mut Heap, _expr: ExpressionId) -> VisitorResult {
 
        Ok(())
 
    }
 
}
 

	
 
pub(crate) struct FunctionStatementReturns {}
 

	
 
impl FunctionStatementReturns {
 
    pub(crate) fn new() -> Self {
 
        FunctionStatementReturns {}
 
    }
 
    fn function_error(&self, position: InputPosition) -> VisitorResult {
 
        Err((position, "Function definition must return".to_string()))
 
    }
 
}
 

	
 
impl Visitor for FunctionStatementReturns {
 
    fn visit_component_definition(&mut self, _h: &mut Heap, _def: ComponentId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_variable_declaration(&mut self, _h: &mut Heap, _decl: VariableId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_block_statement(&mut self, h: &mut Heap, block: BlockStatementId) -> VisitorResult {
 
        let len = h[block].statements.len();
 
        assert!(len > 0);
 
        self.visit_statement(h, h[block].statements[len - 1])
 
    }
 
    fn visit_skip_statement(&mut self, h: &mut Heap, stmt: SkipStatementId) -> VisitorResult {
 
        self.function_error(h[stmt].position)
 
    }
 
    fn visit_break_statement(&mut self, h: &mut Heap, stmt: BreakStatementId) -> VisitorResult {
 
        self.function_error(h[stmt].position)
 
    }
 
    fn visit_continue_statement(
 
        &mut self,
 
        h: &mut Heap,
 
        stmt: ContinueStatementId,
 
    ) -> VisitorResult {
 
        self.function_error(h[stmt].position)
 
    }
 
    fn visit_assert_statement(&mut self, h: &mut Heap, stmt: AssertStatementId) -> VisitorResult {
 
        self.function_error(h[stmt].position)
 
    }
 
    fn visit_new_statement(&mut self, h: &mut Heap, stmt: NewStatementId) -> VisitorResult {
 
        self.function_error(h[stmt].position)
 
    }
 
    fn visit_expression_statement(
 
        &mut self,
 
        h: &mut Heap,
 
        stmt: ExpressionStatementId,
 
    ) -> VisitorResult {
 
        self.function_error(h[stmt].position)
 
    }
 
    fn visit_expression(&mut self, _h: &mut Heap, _expr: ExpressionId) -> VisitorResult {
 
        Ok(())
 
    }
 
}
 

	
 
pub(crate) struct ComponentStatementReturnNew {
 
    illegal_new: bool,
 
    illegal_return: bool,
 
}
 

	
 
impl ComponentStatementReturnNew {
 
    pub(crate) fn new() -> Self {
 
        ComponentStatementReturnNew { illegal_new: false, illegal_return: false }
 
    }
 
}
 

	
 
impl Visitor for ComponentStatementReturnNew {
 
    fn visit_component_definition(&mut self, h: &mut Heap, def: ComponentId) -> VisitorResult {
 
        assert!(!(self.illegal_new || self.illegal_return));
 
        self.illegal_return = true;
 
        recursive_component_definition(self, h, def)?;
 
        self.illegal_return = false;
 
        Ok(())
 
    }
 
    fn visit_primitive_definition(&mut self, h: &mut Heap, def: ComponentId) -> VisitorResult {
 
        assert!(!self.illegal_new);
 
        self.illegal_new = true;
 
        recursive_primitive_definition(self, h, def)?;
 
        self.illegal_new = false;
 
        Ok(())
 
    }
 
    fn visit_function_definition(&mut self, h: &mut Heap, def: FunctionId) -> VisitorResult {
 
        assert!(!(self.illegal_new || self.illegal_return));
 
        self.illegal_new = true;
 
        recursive_function_definition(self, h, def)?;
 
        self.illegal_new = false;
 
        Ok(())
 
    }
 
    fn visit_variable_declaration(&mut self, _h: &mut Heap, _decl: VariableId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_return_statement(&mut self, h: &mut Heap, stmt: ReturnStatementId) -> VisitorResult {
 
        if self.illegal_return {
 
            Err((h[stmt].position, "Component definition must not return".to_string()))
 
        } else {
 
            recursive_return_statement(self, h, stmt)
 
        }
 
    }
 
    fn visit_new_statement(&mut self, h: &mut Heap, stmt: NewStatementId) -> VisitorResult {
 
        if self.illegal_new {
 
            Err((
 
                h[stmt].position,
 
                "Symbol definition contains illegal new statement".to_string(),
 
            ))
 
        } else {
 
            recursive_new_statement(self, h, stmt)
 
        }
 
    }
 
    fn visit_expression(&mut self, _h: &mut Heap, _expr: ExpressionId) -> VisitorResult {
 
        Ok(())
 
    }
 
}
 

	
 
pub(crate) struct CheckBuiltinOccurrences {
 
    legal: bool,
 
}
 

	
 
impl CheckBuiltinOccurrences {
 
    pub(crate) fn new() -> Self {
 
        CheckBuiltinOccurrences { legal: false }
 
    }
 
}
 

	
 
impl Visitor for CheckBuiltinOccurrences {
 
    fn visit_synchronous_statement(
 
        &mut self,
 
        h: &mut Heap,
 
        stmt: SynchronousStatementId,
 
    ) -> VisitorResult {
 
        assert!(!self.legal);
 
        self.legal = true;
 
        recursive_synchronous_statement(self, h, stmt)?;
 
        self.legal = false;
 
        Ok(())
 
    }
 
    fn visit_call_expression(&mut self, h: &mut Heap, expr: CallExpressionId) -> VisitorResult {
 
        match h[expr].method {
 
            Method::Get | Method::Fires => {
 
                if !self.legal {
 
                    return Err((h[expr].position, "Illegal built-in occurrence".to_string()));
 
                }
 
            }
 
            _ => {}
 
        }
 
        recursive_call_expression(self, h, expr)
 
    }
 
}
 

	
 
pub(crate) struct BuildScope {
 
    scope: Option<Scope>,
 
}
 

	
 
impl BuildScope {
 
    pub(crate) fn new() -> Self {
 
        BuildScope { scope: None }
 
    }
 
}
 

	
 
impl Visitor for BuildScope {
 
    fn visit_symbol_definition(&mut self, h: &mut Heap, def: DefinitionId) -> VisitorResult {
 
        assert!(self.scope.is_none());
 
        self.scope = Some(Scope::Definition(def));
 
        recursive_symbol_definition(self, h, def)?;
 
        self.scope = None;
 
        Ok(())
 
    }
 
    fn visit_block_statement(&mut self, h: &mut Heap, stmt: BlockStatementId) -> VisitorResult {
 
        assert!(!self.scope.is_none());
 
        let old = self.scope;
 
        // First store the current scope
 
        h[stmt].parent_scope = self.scope;
 
        // Then move scope down to current block
 
        self.scope = Some(Scope::Regular(stmt));
 
        recursive_block_statement(self, h, stmt)?;
 
        // Move scope back up
 
        self.scope = old;
 
        Ok(())
 
    }
 
    fn visit_synchronous_statement(
 
        &mut self,
 
        h: &mut Heap,
 
        stmt: SynchronousStatementId,
 
    ) -> VisitorResult {
 
        assert!(!self.scope.is_none());
 
        let old = self.scope;
 
        // First store the current scope
 
        h[stmt].parent_scope = self.scope;
 
        // Then move scope down to current sync
 
        // TODO: Should be legal-ish, but very wrong
 
        self.scope = Some(Scope::Synchronous((stmt, BlockStatementId(stmt.upcast()))));
 
        recursive_synchronous_statement(self, h, stmt)?;
 
        // Move scope back up
 
        self.scope = old;
 
        Ok(())
 
    }
 
    fn visit_expression(&mut self, _h: &mut Heap, _expr: ExpressionId) -> VisitorResult {
 
        Ok(())
 
    }
 
}
 

	
 
pub(crate) struct UniqueStatementId(StatementId);
 

	
 
pub(crate) struct LinkStatements {
 
    prev: Option<UniqueStatementId>,
 
}
 

	
 
impl LinkStatements {
 
    pub(crate) fn new() -> Self {
 
        LinkStatements { prev: None }
 
@@ -924,620 +924,620 @@ impl Visitor for LinkStatements {
 
        // The body's next statement points to the pseudo element
 
        if let Some(UniqueStatementId(prev)) = self.prev.take() {
 
            h[prev].link_next(end_sync_id.upcast());
 
        }
 
        // Use the pseudo-statement as the statement where the next pointer is updated
 
        // self.prev = Some(UniqueStatementId(end_sync_id.upcast()));
 
        Ok(())
 
    }
 
    fn visit_end_synchronous_statement(&mut self, _h: &mut Heap, stmt: EndSynchronousStatementId) -> VisitorResult {
 
        assert!(self.prev.is_none());
 
        self.prev = Some(UniqueStatementId(stmt.upcast()));
 
        Ok(())
 
    }
 
    fn visit_return_statement(&mut self, _h: &mut Heap, _stmt: ReturnStatementId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_assert_statement(&mut self, _h: &mut Heap, stmt: AssertStatementId) -> VisitorResult {
 
        self.prev = Some(UniqueStatementId(stmt.upcast()));
 
        Ok(())
 
    }
 
    fn visit_goto_statement(&mut self, _h: &mut Heap, _stmt: GotoStatementId) -> VisitorResult {
 
        Ok(())
 
    }
 
    fn visit_new_statement(&mut self, _h: &mut Heap, stmt: NewStatementId) -> VisitorResult {
 
        self.prev = Some(UniqueStatementId(stmt.upcast()));
 
        Ok(())
 
    }
 
    fn visit_expression_statement(
 
        &mut self,
 
        _h: &mut Heap,
 
        stmt: ExpressionStatementId,
 
    ) -> VisitorResult {
 
        self.prev = Some(UniqueStatementId(stmt.upcast()));
 
        Ok(())
 
    }
 
    fn visit_expression(&mut self, _h: &mut Heap, _expr: ExpressionId) -> VisitorResult {
 
        Ok(())
 
    }
 
}
 

	
 
pub(crate) struct BuildLabels {
 
    block: Option<BlockStatementId>,
 
    sync_enclosure: Option<SynchronousStatementId>,
 
}
 

	
 
impl BuildLabels {
 
    pub(crate) fn new() -> Self {
 
        BuildLabels { block: None, sync_enclosure: None }
 
    }
 
}
 

	
 
impl Visitor for BuildLabels {
 
    fn visit_block_statement(&mut self, h: &mut Heap, stmt: BlockStatementId) -> VisitorResult {
 
        assert_eq!(self.block, h[stmt].parent_block(h));
 
        let old = self.block;
 
        self.block = Some(stmt);
 
        recursive_block_statement(self, h, stmt)?;
 
        self.block = old;
 
        Ok(())
 
    }
 
    fn visit_labeled_statement(&mut self, h: &mut Heap, stmt: LabeledStatementId) -> VisitorResult {
 
        assert!(!self.block.is_none());
 
        // Store label in current block (on the fly)
 
        h[self.block.unwrap()].labels.push(stmt);
 
        // Update synchronous scope of label
 
        h[stmt].in_sync = self.sync_enclosure;
 
        recursive_labeled_statement(self, h, stmt)
 
    }
 
    fn visit_while_statement(&mut self, h: &mut Heap, stmt: WhileStatementId) -> VisitorResult {
 
        h[stmt].in_sync = self.sync_enclosure;
 
        recursive_while_statement(self, h, stmt)
 
    }
 
    fn visit_synchronous_statement(
 
        &mut self,
 
        h: &mut Heap,
 
        stmt: SynchronousStatementId,
 
    ) -> VisitorResult {
 
        assert!(self.sync_enclosure.is_none());
 
        self.sync_enclosure = Some(stmt);
 
        recursive_synchronous_statement(self, h, stmt)?;
 
        self.sync_enclosure = None;
 
        Ok(())
 
    }
 
    fn visit_expression(&mut self, _h: &mut Heap, _expr: ExpressionId) -> VisitorResult {
 
        Ok(())
 
    }
 
}
 

	
 
pub(crate) struct ResolveLabels {
 
    block: Option<BlockStatementId>,
 
    while_enclosure: Option<WhileStatementId>,
 
    sync_enclosure: Option<SynchronousStatementId>,
 
}
 

	
 
impl ResolveLabels {
 
    pub(crate) fn new() -> Self {
 
        ResolveLabels { block: None, while_enclosure: None, sync_enclosure: None }
 
    }
 
    fn check_duplicate_impl(
 
        h: &Heap,
 
        block: Option<BlockStatementId>,
 
        stmt: LabeledStatementId,
 
    ) -> VisitorResult {
 
        if let Some(block) = block {
 
            // Checking the parent first is important. Otherwise, labels
 
            // overshadow previously defined labels: and this is illegal!
 
            ResolveLabels::check_duplicate_impl(h, h[block].parent_block(h), stmt)?;
 
            // For the current block, check for a duplicate.
 
            for &other_stmt in h[block].labels.iter() {
 
                if other_stmt == stmt {
 
                    continue;
 
                } else {
 
                    if h[other_stmt].label.value == h[stmt].label.value {
 
                        return Err((h[stmt].position, "Duplicate label".to_string()));
 
                    }
 
                }
 
            }
 
        }
 
        Ok(())
 
    }
 
    fn check_duplicate(&self, h: &Heap, stmt: LabeledStatementId) -> VisitorResult {
 
        ResolveLabels::check_duplicate_impl(h, self.block, stmt)
 
    }
 
    fn get_target(
 
        &self,
 
        h: &Heap,
 
        id: &Identifier,
 
    ) -> Result<LabeledStatementId, VisitorError> {
 
        if let Some(stmt) = ResolveLabels::find_target(h, self.block, id) {
 
            Ok(stmt)
 
        } else {
 
            Err((id.position, "Unresolved label".to_string()))
 
        }
 
    }
 
    fn find_target(
 
        h: &Heap,
 
        block: Option<BlockStatementId>,
 
        id: &Identifier,
 
    ) -> Option<LabeledStatementId> {
 
        if let Some(block) = block {
 
            // It does not matter in what order we find the labels.
 
            // If there are duplicates: that is checked elsewhere.
 
            for &stmt in h[block].labels.iter() {
 
                if h[stmt].label.value == id.value {
 
                    return Some(stmt);
 
                }
 
            }
 
            if let Some(stmt) = ResolveLabels::find_target(h, h[block].parent_block(h), id) {
 
                return Some(stmt);
 
            }
 
        }
 
        None
 
    }
 
}
 

	
 
impl Visitor for ResolveLabels {
 
    fn visit_block_statement(&mut self, h: &mut Heap, stmt: BlockStatementId) -> VisitorResult {
 
        assert_eq!(self.block, h[stmt].parent_block(h));
 
        let old = self.block;
 
        self.block = Some(stmt);
 
        recursive_block_statement(self, h, stmt)?;
 
        self.block = old;
 
        Ok(())
 
    }
 
    fn visit_labeled_statement(&mut self, h: &mut Heap, stmt: LabeledStatementId) -> VisitorResult {
 
        assert!(!self.block.is_none());
 
        self.check_duplicate(h, stmt)?;
 
        recursive_labeled_statement(self, h, stmt)
 
    }
 
    fn visit_while_statement(&mut self, h: &mut Heap, stmt: WhileStatementId) -> VisitorResult {
 
        let old = self.while_enclosure;
 
        self.while_enclosure = Some(stmt);
 
        recursive_while_statement(self, h, stmt)?;
 
        self.while_enclosure = old;
 
        Ok(())
 
    }
 
    fn visit_break_statement(&mut self, h: &mut Heap, stmt: BreakStatementId) -> VisitorResult {
 
        let the_while;
 
        if let Some(label) = &h[stmt].label {
 
            let target = self.get_target(h, label)?;
 
            let target = &h[h[target].body];
 
            if !target.is_while() {
 
                return Err((
 
                    h[stmt].position,
 
                    "Illegal break: target not a while statement".to_string(),
 
                ));
 
            }
 
            the_while = target.as_while();
 
            // TODO: check if break is nested under while
 
        } else {
 
            if self.while_enclosure.is_none() {
 
                return Err((
 
                    h[stmt].position,
 
                    "Illegal break: no surrounding while statement".to_string(),
 
                ));
 
            }
 
            the_while = &h[self.while_enclosure.unwrap()];
 
            // break is always nested under while, by recursive vistor
 
        }
 
        if the_while.in_sync != self.sync_enclosure {
 
            return Err((
 
                h[stmt].position,
 
                "Illegal break: synchronous statement escape".to_string(),
 
            ));
 
        }
 
        h[stmt].target = the_while.end_while;
 
        Ok(())
 
    }
 
    fn visit_continue_statement(
 
        &mut self,
 
        h: &mut Heap,
 
        stmt: ContinueStatementId,
 
    ) -> VisitorResult {
 
        let the_while;
 
        if let Some(label) = &h[stmt].label {
 
            let target = self.get_target(h, label)?;
 
            let target = &h[h[target].body];
 
            if !target.is_while() {
 
                return Err((
 
                    h[stmt].position,
 
                    "Illegal continue: target not a while statement".to_string(),
 
                ));
 
            }
 
            the_while = target.as_while();
 
            // TODO: check if continue is nested under while
 
        } else {
 
            if self.while_enclosure.is_none() {
 
                return Err((
 
                    h[stmt].position,
 
                    "Illegal continue: no surrounding while statement".to_string(),
 
                ));
 
            }
 
            the_while = &h[self.while_enclosure.unwrap()];
 
            // continue is always nested under while, by recursive vistor
 
        }
 
        if the_while.in_sync != self.sync_enclosure {
 
            return Err((
 
                h[stmt].position,
 
                "Illegal continue: synchronous statement escape".to_string(),
 
            ));
 
        }
 
        h[stmt].target = Some(the_while.this);
 
        Ok(())
 
    }
 
    fn visit_synchronous_statement(
 
        &mut self,
 
        h: &mut Heap,
 
        stmt: SynchronousStatementId,
 
    ) -> VisitorResult {
 
        assert!(self.sync_enclosure.is_none());
 
        self.sync_enclosure = Some(stmt);
 
        recursive_synchronous_statement(self, h, stmt)?;
 
        self.sync_enclosure = None;
 
        Ok(())
 
    }
 
    fn visit_goto_statement(&mut self, h: &mut Heap, stmt: GotoStatementId) -> VisitorResult {
 
        let target = self.get_target(h, &h[stmt].label)?;
 
        if h[target].in_sync != self.sync_enclosure {
 
            return Err((
 
                h[stmt].position,
 
                "Illegal goto: synchronous statement escape".to_string(),
 
            ));
 
        }
 
        h[stmt].target = Some(target);
 
        Ok(())
 
    }
 
    fn visit_expression(&mut self, _h: &mut Heap, _expr: ExpressionId) -> VisitorResult {
 
        Ok(())
 
    }
 
}
 

	
 
pub(crate) struct AssignableExpressions {
 
    assignable: bool,
 
}
 

	
 
impl AssignableExpressions {
 
    pub(crate) fn new() -> Self {
 
        AssignableExpressions { assignable: false }
 
    }
 
    fn error(&self, position: InputPosition) -> VisitorResult {
 
        Err((position, "Unassignable expression".to_string()))
 
    }
 
}
 

	
 
impl Visitor for AssignableExpressions {
 
    fn visit_assignment_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: AssignmentExpressionId,
 
    ) -> VisitorResult {
 
        if self.assignable {
 
            self.error(h[expr].position)
 
        } else {
 
            self.assignable = true;
 
            self.visit_expression(h, h[expr].left)?;
 
            self.assignable = false;
 
            self.visit_expression(h, h[expr].right)
 
        }
 
    }
 
    fn visit_conditional_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: ConditionalExpressionId,
 
    ) -> VisitorResult {
 
        if self.assignable {
 
            self.error(h[expr].position)
 
        } else {
 
            recursive_conditional_expression(self, h, expr)
 
        }
 
    }
 
    fn visit_binary_expression(&mut self, h: &mut Heap, expr: BinaryExpressionId) -> VisitorResult {
 
        if self.assignable {
 
            self.error(h[expr].position)
 
        } else {
 
            recursive_binary_expression(self, h, expr)
 
        }
 
    }
 
    fn visit_unary_expression(&mut self, h: &mut Heap, expr: UnaryExpressionId) -> VisitorResult {
 
        if self.assignable {
 
            self.error(h[expr].position)
 
        } else {
 
            match h[expr].operation {
 
                UnaryOperation::PostDecrement
 
                | UnaryOperation::PreDecrement
 
                | UnaryOperation::PostIncrement
 
                | UnaryOperation::PreIncrement => {
 
                    self.assignable = true;
 
                    recursive_unary_expression(self, h, expr)?;
 
                    self.assignable = false;
 
                    Ok(())
 
                }
 
                _ => recursive_unary_expression(self, h, expr),
 
            }
 
        }
 
    }
 
    fn visit_indexing_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: IndexingExpressionId,
 
    ) -> VisitorResult {
 
        let old = self.assignable;
 
        self.assignable = false;
 
        recursive_indexing_expression(self, h, expr)?;
 
        self.assignable = old;
 
        Ok(())
 
    }
 
    fn visit_slicing_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: SlicingExpressionId,
 
    ) -> VisitorResult {
 
        let old = self.assignable;
 
        self.assignable = false;
 
        recursive_slicing_expression(self, h, expr)?;
 
        self.assignable = old;
 
        Ok(())
 
    }
 
    fn visit_select_expression(&mut self, h: &mut Heap, expr: SelectExpressionId) -> VisitorResult {
 
        if h[expr].field.is_length() && self.assignable {
 
            return self.error(h[expr].position);
 
        }
 
        let old = self.assignable;
 
        self.assignable = false;
 
        recursive_select_expression(self, h, expr)?;
 
        self.assignable = old;
 
        Ok(())
 
    }
 
    fn visit_array_expression(&mut self, h: &mut Heap, expr: ArrayExpressionId) -> VisitorResult {
 
        if self.assignable {
 
            self.error(h[expr].position)
 
        } else {
 
            recursive_array_expression(self, h, expr)
 
        }
 
    }
 
    fn visit_call_expression(&mut self, h: &mut Heap, expr: CallExpressionId) -> VisitorResult {
 
        if self.assignable {
 
            self.error(h[expr].position)
 
        } else {
 
            recursive_call_expression(self, h, expr)
 
        }
 
    }
 
    fn visit_constant_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: ConstantExpressionId,
 
        expr: LiteralExpressionId,
 
    ) -> VisitorResult {
 
        if self.assignable {
 
            self.error(h[expr].position)
 
        } else {
 
            Ok(())
 
        }
 
    }
 
    fn visit_variable_expression(
 
        &mut self,
 
        _h: &mut Heap,
 
        _expr: VariableExpressionId,
 
    ) -> VisitorResult {
 
        Ok(())
 
    }
 
}
 

	
 
pub(crate) struct IndexableExpressions {
 
    indexable: bool,
 
}
 

	
 
impl IndexableExpressions {
 
    pub(crate) fn new() -> Self {
 
        IndexableExpressions { indexable: false }
 
    }
 
    fn error(&self, position: InputPosition) -> VisitorResult {
 
        Err((position, "Unindexable expression".to_string()))
 
    }
 
}
 

	
 
impl Visitor for IndexableExpressions {
 
    fn visit_assignment_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: AssignmentExpressionId,
 
    ) -> VisitorResult {
 
        if self.indexable {
 
            self.error(h[expr].position)
 
        } else {
 
            recursive_assignment_expression(self, h, expr)
 
        }
 
    }
 
    fn visit_conditional_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: ConditionalExpressionId,
 
    ) -> VisitorResult {
 
        let old = self.indexable;
 
        self.indexable = false;
 
        self.visit_expression(h, h[expr].test)?;
 
        self.indexable = old;
 
        self.visit_expression(h, h[expr].true_expression)?;
 
        self.visit_expression(h, h[expr].false_expression)
 
    }
 
    fn visit_binary_expression(&mut self, h: &mut Heap, expr: BinaryExpressionId) -> VisitorResult {
 
        if self.indexable && h[expr].operation != BinaryOperator::Concatenate {
 
            self.error(h[expr].position)
 
        } else {
 
            recursive_binary_expression(self, h, expr)
 
        }
 
    }
 
    fn visit_unary_expression(&mut self, h: &mut Heap, expr: UnaryExpressionId) -> VisitorResult {
 
        if self.indexable {
 
            self.error(h[expr].position)
 
        } else {
 
            recursive_unary_expression(self, h, expr)
 
        }
 
    }
 
    fn visit_indexing_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: IndexingExpressionId,
 
    ) -> VisitorResult {
 
        let old = self.indexable;
 
        self.indexable = true;
 
        self.visit_expression(h, h[expr].subject)?;
 
        self.indexable = false;
 
        self.visit_expression(h, h[expr].index)?;
 
        self.indexable = old;
 
        Ok(())
 
    }
 
    fn visit_slicing_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: SlicingExpressionId,
 
    ) -> VisitorResult {
 
        let old = self.indexable;
 
        self.indexable = true;
 
        self.visit_expression(h, h[expr].subject)?;
 
        self.indexable = false;
 
        self.visit_expression(h, h[expr].from_index)?;
 
        self.visit_expression(h, h[expr].to_index)?;
 
        self.indexable = old;
 
        Ok(())
 
    }
 
    fn visit_select_expression(&mut self, h: &mut Heap, expr: SelectExpressionId) -> VisitorResult {
 
        let old = self.indexable;
 
        self.indexable = false;
 
        recursive_select_expression(self, h, expr)?;
 
        self.indexable = old;
 
        Ok(())
 
    }
 
    fn visit_array_expression(&mut self, h: &mut Heap, expr: ArrayExpressionId) -> VisitorResult {
 
        let old = self.indexable;
 
        self.indexable = false;
 
        recursive_array_expression(self, h, expr)?;
 
        self.indexable = old;
 
        Ok(())
 
    }
 
    fn visit_call_expression(&mut self, h: &mut Heap, expr: CallExpressionId) -> VisitorResult {
 
        let old = self.indexable;
 
        self.indexable = false;
 
        recursive_call_expression(self, h, expr)?;
 
        self.indexable = old;
 
        Ok(())
 
    }
 
    fn visit_constant_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: ConstantExpressionId,
 
        expr: LiteralExpressionId,
 
    ) -> VisitorResult {
 
        if self.indexable {
 
            self.error(h[expr].position)
 
        } else {
 
            Ok(())
 
        }
 
    }
 
}
 

	
 
pub(crate) struct SelectableExpressions {
 
    selectable: bool,
 
}
 

	
 
impl SelectableExpressions {
 
    pub(crate) fn new() -> Self {
 
        SelectableExpressions { selectable: false }
 
    }
 
    fn error(&self, position: InputPosition) -> VisitorResult {
 
        Err((position, "Unselectable expression".to_string()))
 
    }
 
}
 

	
 
impl Visitor for SelectableExpressions {
 
    fn visit_assignment_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: AssignmentExpressionId,
 
    ) -> VisitorResult {
 
        // left-hand side of assignment can be skipped
 
        let old = self.selectable;
 
        self.selectable = false;
 
        self.visit_expression(h, h[expr].right)?;
 
        self.selectable = old;
 
        Ok(())
 
    }
 
    fn visit_conditional_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: ConditionalExpressionId,
 
    ) -> VisitorResult {
 
        let old = self.selectable;
 
        self.selectable = false;
 
        self.visit_expression(h, h[expr].test)?;
 
        self.selectable = old;
 
        self.visit_expression(h, h[expr].true_expression)?;
 
        self.visit_expression(h, h[expr].false_expression)
 
    }
 
    fn visit_binary_expression(&mut self, h: &mut Heap, expr: BinaryExpressionId) -> VisitorResult {
 
        if self.selectable && h[expr].operation != BinaryOperator::Concatenate {
 
            self.error(h[expr].position)
 
        } else {
 
            recursive_binary_expression(self, h, expr)
 
        }
 
    }
 
    fn visit_unary_expression(&mut self, h: &mut Heap, expr: UnaryExpressionId) -> VisitorResult {
 
        if self.selectable {
 
            self.error(h[expr].position)
 
        } else {
 
            recursive_unary_expression(self, h, expr)
 
        }
 
    }
 
    fn visit_indexing_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: IndexingExpressionId,
 
    ) -> VisitorResult {
 
        let old = self.selectable;
 
        self.selectable = false;
 
        recursive_indexing_expression(self, h, expr)?;
 
        self.selectable = old;
 
        Ok(())
 
    }
 
    fn visit_slicing_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: SlicingExpressionId,
 
    ) -> VisitorResult {
 
        let old = self.selectable;
 
        self.selectable = false;
 
        recursive_slicing_expression(self, h, expr)?;
 
        self.selectable = old;
 
        Ok(())
 
    }
 
    fn visit_select_expression(&mut self, h: &mut Heap, expr: SelectExpressionId) -> VisitorResult {
 
        let old = self.selectable;
 
        self.selectable = false;
 
        recursive_select_expression(self, h, expr)?;
 
        self.selectable = old;
 
        Ok(())
 
    }
 
    fn visit_array_expression(&mut self, h: &mut Heap, expr: ArrayExpressionId) -> VisitorResult {
 
        let old = self.selectable;
 
        self.selectable = false;
 
        recursive_array_expression(self, h, expr)?;
 
        self.selectable = old;
 
        Ok(())
 
    }
 
    fn visit_call_expression(&mut self, h: &mut Heap, expr: CallExpressionId) -> VisitorResult {
 
        let old = self.selectable;
 
        self.selectable = false;
 
        recursive_call_expression(self, h, expr)?;
 
        self.selectable = old;
 
        Ok(())
 
    }
 
    fn visit_constant_expression(
 
        &mut self,
 
        h: &mut Heap,
 
        expr: ConstantExpressionId,
 
        expr: LiteralExpressionId,
 
    ) -> VisitorResult {
 
        if self.selectable {
 
            self.error(h[expr].position)
 
        } else {
 
            Ok(())
 
        }
 
    }
 
}
src/protocol/parser/type_resolver.rs
Show inline comments
 
@@ -816,1996 +816,1996 @@ pub(crate) type ResolveQueue = Vec<ResolveQueueElement>;
 
/// This particular visitor will recurse depth-first into the AST and ensures
 
/// that all expressions have the appropriate types.
 
pub(crate) struct TypeResolvingVisitor {
 
    // Current definition we're typechecking.
 
    definition_type: DefinitionType,
 
    poly_vars: Vec<ConcreteType>,
 

	
 
    // Buffers for iteration over substatements and subexpressions
 
    stmt_buffer: Vec<StatementId>,
 
    expr_buffer: Vec<ExpressionId>,
 

	
 
    // Mapping from parser type to inferred type. We attempt to continue to
 
    // specify these types until we're stuck or we've fully determined the type.
 
    var_types: HashMap<VariableId, VarData>,      // types of variables
 
    expr_types: HashMap<ExpressionId, InferenceType>,   // types of expressions
 
    extra_data: HashMap<ExpressionId, ExtraData>,       // data for function call inference
 
    // Keeping track of which expressions need to be reinferred because the
 
    // expressions they're linked to made progression on an associated type
 
    expr_queued: HashSet<ExpressionId>,
 
}
 

	
 
// TODO: @rename used for calls and struct literals, maybe union literals?
 
struct ExtraData {
 
    /// Progression of polymorphic variables (if any)
 
    poly_vars: Vec<InferenceType>,
 
    /// Progression of types of call arguments or struct members
 
    embedded: Vec<InferenceType>,
 
    returned: InferenceType,
 
}
 

	
 
struct VarData {
 
    /// Type of the variable
 
    var_type: InferenceType,
 
    /// VariableExpressions that use the variable
 
    used_at: Vec<ExpressionId>,
 
    /// For channel statements we link to the other variable such that when one
 
    /// channel's interior type is resolved, we can also resolve the other one.
 
    linked_var: Option<VariableId>,
 
}
 

	
 
impl VarData {
 
    fn new_channel(var_type: InferenceType, other_port: VariableId) -> Self {
 
        Self{ var_type, used_at: Vec::new(), linked_var: Some(other_port) }
 
    }
 
    fn new_local(var_type: InferenceType) -> Self {
 
        Self{ var_type, used_at: Vec::new(), linked_var: None }
 
    }
 
}
 

	
 
impl TypeResolvingVisitor {
 
    pub(crate) fn new() -> Self {
 
        TypeResolvingVisitor{
 
            definition_type: DefinitionType::None,
 
            poly_vars: Vec::new(),
 
            stmt_buffer: Vec::with_capacity(STMT_BUFFER_INIT_CAPACITY),
 
            expr_buffer: Vec::with_capacity(EXPR_BUFFER_INIT_CAPACITY),
 
            var_types: HashMap::new(),
 
            expr_types: HashMap::new(),
 
            extra_data: HashMap::new(),
 
            expr_queued: HashSet::new(),
 
        }
 
    }
 

	
 
    // TODO: @cleanup Unsure about this, maybe a pattern will arise after
 
    //  a while.
 
    pub(crate) fn queue_module_definitions(ctx: &Ctx, queue: &mut ResolveQueue) {
 
        let root_id = ctx.module.root_id;
 
        let root = &ctx.heap.protocol_descriptions[root_id];
 
        for definition_id in &root.definitions {
 
            let definition = &ctx.heap[*definition_id];
 
            match definition {
 
                Definition::Function(definition) => {
 
                    if definition.poly_vars.is_empty() {
 
                        queue.push(ResolveQueueElement{
 
                            root_id,
 
                            definition_id: *definition_id,
 
                            monomorph_types: Vec::new(),
 
                        })
 
                    }
 
                },
 
                Definition::Component(definition) => {
 
                    if definition.poly_vars.is_empty() {
 
                        queue.push(ResolveQueueElement{
 
                            root_id,
 
                            definition_id: *definition_id,
 
                            monomorph_types: Vec::new(),
 
                        })
 
                    }
 
                },
 
                Definition::Enum(_) | Definition::Struct(_) => {},
 
            }
 
        }
 
    }
 

	
 
    pub(crate) fn handle_module_definition(
 
        &mut self, ctx: &mut Ctx, queue: &mut ResolveQueue, element: ResolveQueueElement
 
    ) -> VisitorResult {
 
        // Visit the definition
 
        debug_assert_eq!(ctx.module.root_id, element.root_id);
 
        self.reset();
 
        self.poly_vars.clear();
 
        self.poly_vars.extend(element.monomorph_types.iter().cloned());
 
        self.visit_definition(ctx, element.definition_id)?;
 

	
 
        // Keep resolving types
 
        self.resolve_types(ctx, queue)?;
 
        Ok(())
 
    }
 

	
 
    fn reset(&mut self) {
 
        self.definition_type = DefinitionType::None;
 
        self.poly_vars.clear();
 
        self.stmt_buffer.clear();
 
        self.expr_buffer.clear();
 
        self.var_types.clear();
 
        self.expr_types.clear();
 
        self.extra_data.clear();
 
        self.expr_queued.clear();
 
    }
 
}
 

	
 
impl Visitor2 for TypeResolvingVisitor {
 
    // Definitions
 

	
 
    fn visit_component_definition(&mut self, ctx: &mut Ctx, id: ComponentId) -> VisitorResult {
 
        self.definition_type = DefinitionType::Component(id);
 

	
 
        let comp_def = &ctx.heap[id];
 
        debug_assert_eq!(comp_def.poly_vars.len(), self.poly_vars.len(), "component polyvars do not match imposed polyvars");
 

	
 
        debug_log!("{}", "-".repeat(50));
 
        debug_log!("Visiting component '{}': {}", &String::from_utf8_lossy(&comp_def.identifier.value), id.0.index);
 
        debug_log!("{}", "-".repeat(50));
 

	
 
        for param_id in comp_def.parameters.clone() {
 
            let param = &ctx.heap[param_id];
 
            let var_type = self.determine_inference_type_from_parser_type(ctx, param.parser_type, true);
 
            debug_assert!(var_type.is_done, "expected component arguments to be concrete types");
 
            self.var_types.insert(param_id.upcast(), VarData::new_local(var_type));
 
        }
 

	
 
        let body_stmt_id = ctx.heap[id].body;
 
        self.visit_stmt(ctx, body_stmt_id)
 
    }
 

	
 
    fn visit_function_definition(&mut self, ctx: &mut Ctx, id: FunctionId) -> VisitorResult {
 
        self.definition_type = DefinitionType::Function(id);
 

	
 
        let func_def = &ctx.heap[id];
 
        debug_assert_eq!(func_def.poly_vars.len(), self.poly_vars.len(), "function polyvars do not match imposed polyvars");
 

	
 
        debug_log!("{}", "-".repeat(50));
 
        debug_log!("Visiting function '{}': {}", &String::from_utf8_lossy(&func_def.identifier.value), id.0.index);
 
        debug_log!("{}", "-".repeat(50));
 

	
 
        for param_id in func_def.parameters.clone() {
 
            let param = &ctx.heap[param_id];
 
            let var_type = self.determine_inference_type_from_parser_type(ctx, param.parser_type, true);
 
            debug_assert!(var_type.is_done, "expected function arguments to be concrete types");
 
            self.var_types.insert(param_id.upcast(), VarData::new_local(var_type));
 
        }
 

	
 
        let body_stmt_id = ctx.heap[id].body;
 
        self.visit_stmt(ctx, body_stmt_id)
 
    }
 

	
 
    // Statements
 

	
 
    fn visit_block_stmt(&mut self, ctx: &mut Ctx, id: BlockStatementId) -> VisitorResult {
 
        // Transfer statements for traversal
 
        let block = &ctx.heap[id];
 

	
 
        for stmt_id in block.statements.clone() {
 
            self.visit_stmt(ctx, stmt_id)?;
 
        }
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_local_memory_stmt(&mut self, ctx: &mut Ctx, id: MemoryStatementId) -> VisitorResult {
 
        let memory_stmt = &ctx.heap[id];
 

	
 
        let local = &ctx.heap[memory_stmt.variable];
 
        let var_type = self.determine_inference_type_from_parser_type(ctx, local.parser_type, true);
 
        self.var_types.insert(memory_stmt.variable.upcast(), VarData::new_local(var_type));
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_local_channel_stmt(&mut self, ctx: &mut Ctx, id: ChannelStatementId) -> VisitorResult {
 
        let channel_stmt = &ctx.heap[id];
 

	
 
        let from_local = &ctx.heap[channel_stmt.from];
 
        let from_var_type = self.determine_inference_type_from_parser_type(ctx, from_local.parser_type, true);
 
        self.var_types.insert(from_local.this.upcast(), VarData::new_channel(from_var_type, channel_stmt.to.upcast()));
 

	
 
        let to_local = &ctx.heap[channel_stmt.to];
 
        let to_var_type = self.determine_inference_type_from_parser_type(ctx, to_local.parser_type, true);
 
        self.var_types.insert(to_local.this.upcast(), VarData::new_channel(to_var_type, channel_stmt.from.upcast()));
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_labeled_stmt(&mut self, ctx: &mut Ctx, id: LabeledStatementId) -> VisitorResult {
 
        let labeled_stmt = &ctx.heap[id];
 
        let substmt_id = labeled_stmt.body;
 
        self.visit_stmt(ctx, substmt_id)
 
    }
 

	
 
    fn visit_if_stmt(&mut self, ctx: &mut Ctx, id: IfStatementId) -> VisitorResult {
 
        let if_stmt = &ctx.heap[id];
 

	
 
        let true_body_id = if_stmt.true_body;
 
        let false_body_id = if_stmt.false_body;
 
        let test_expr_id = if_stmt.test;
 

	
 
        self.visit_expr(ctx, test_expr_id)?;
 
        self.visit_stmt(ctx, true_body_id)?;
 
        self.visit_stmt(ctx, false_body_id)?;
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_while_stmt(&mut self, ctx: &mut Ctx, id: WhileStatementId) -> VisitorResult {
 
        let while_stmt = &ctx.heap[id];
 

	
 
        let body_id = while_stmt.body;
 
        let test_expr_id = while_stmt.test;
 

	
 
        self.visit_expr(ctx, test_expr_id)?;
 
        self.visit_stmt(ctx, body_id)?;
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_synchronous_stmt(&mut self, ctx: &mut Ctx, id: SynchronousStatementId) -> VisitorResult {
 
        let sync_stmt = &ctx.heap[id];
 
        let body_id = sync_stmt.body;
 

	
 
        self.visit_stmt(ctx, body_id)
 
    }
 

	
 
    fn visit_return_stmt(&mut self, ctx: &mut Ctx, id: ReturnStatementId) -> VisitorResult {
 
        let return_stmt = &ctx.heap[id];
 
        let expr_id = return_stmt.expression;
 

	
 
        self.visit_expr(ctx, expr_id)
 
    }
 

	
 
    fn visit_assert_stmt(&mut self, ctx: &mut Ctx, id: AssertStatementId) -> VisitorResult {
 
        let assert_stmt = &ctx.heap[id];
 
        let test_expr_id = assert_stmt.expression;
 

	
 
        self.visit_expr(ctx, test_expr_id)
 
    }
 

	
 
    fn visit_new_stmt(&mut self, ctx: &mut Ctx, id: NewStatementId) -> VisitorResult {
 
        let new_stmt = &ctx.heap[id];
 
        let call_expr_id = new_stmt.expression;
 

	
 
        self.visit_call_expr(ctx, call_expr_id)
 
    }
 

	
 
    fn visit_expr_stmt(&mut self, ctx: &mut Ctx, id: ExpressionStatementId) -> VisitorResult {
 
        let expr_stmt = &ctx.heap[id];
 
        let subexpr_id = expr_stmt.expression;
 

	
 
        self.visit_expr(ctx, subexpr_id)
 
    }
 

	
 
    // Expressions
 

	
 
    fn visit_assignment_expr(&mut self, ctx: &mut Ctx, id: AssignmentExpressionId) -> VisitorResult {
 
        let upcast_id = id.upcast();
 
        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
 

	
 
        let assign_expr = &ctx.heap[id];
 
        let left_expr_id = assign_expr.left;
 
        let right_expr_id = assign_expr.right;
 

	
 
        self.visit_expr(ctx, left_expr_id)?;
 
        self.visit_expr(ctx, right_expr_id)?;
 

	
 
        self.progress_assignment_expr(ctx, id)
 
    }
 

	
 
    fn visit_conditional_expr(&mut self, ctx: &mut Ctx, id: ConditionalExpressionId) -> VisitorResult {
 
        let upcast_id = id.upcast();
 
        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
 

	
 
        let conditional_expr = &ctx.heap[id];
 
        let test_expr_id = conditional_expr.test;
 
        let true_expr_id = conditional_expr.true_expression;
 
        let false_expr_id = conditional_expr.false_expression;
 

	
 
        self.expr_types.insert(test_expr_id, InferenceType::new(false, true, vec![InferenceTypePart::Bool]));
 
        self.visit_expr(ctx, test_expr_id)?;
 
        self.visit_expr(ctx, true_expr_id)?;
 
        self.visit_expr(ctx, false_expr_id)?;
 

	
 
        self.progress_conditional_expr(ctx, id)
 
    }
 

	
 
    fn visit_binary_expr(&mut self, ctx: &mut Ctx, id: BinaryExpressionId) -> VisitorResult {
 
        let upcast_id = id.upcast();
 
        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
 

	
 
        let binary_expr = &ctx.heap[id];
 
        let lhs_expr_id = binary_expr.left;
 
        let rhs_expr_id = binary_expr.right;
 

	
 
        self.visit_expr(ctx, lhs_expr_id)?;
 
        self.visit_expr(ctx, rhs_expr_id)?;
 

	
 
        self.progress_binary_expr(ctx, id)
 
    }
 

	
 
    fn visit_unary_expr(&mut self, ctx: &mut Ctx, id: UnaryExpressionId) -> VisitorResult {
 
        let upcast_id = id.upcast();
 
        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
 

	
 
        let unary_expr = &ctx.heap[id];
 
        let arg_expr_id = unary_expr.expression;
 

	
 
        self.visit_expr(ctx, arg_expr_id)?;
 

	
 
        self.progress_unary_expr(ctx, id)
 
    }
 

	
 
    fn visit_indexing_expr(&mut self, ctx: &mut Ctx, id: IndexingExpressionId) -> VisitorResult {
 
        let upcast_id = id.upcast();
 
        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
 

	
 
        let indexing_expr = &ctx.heap[id];
 
        let subject_expr_id = indexing_expr.subject;
 
        let index_expr_id = indexing_expr.index;
 

	
 
        self.visit_expr(ctx, subject_expr_id)?;
 
        self.visit_expr(ctx, index_expr_id)?;
 

	
 
        self.progress_indexing_expr(ctx, id)
 
    }
 

	
 
    fn visit_slicing_expr(&mut self, ctx: &mut Ctx, id: SlicingExpressionId) -> VisitorResult {
 
        let upcast_id = id.upcast();
 
        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
 

	
 
        let slicing_expr = &ctx.heap[id];
 
        let subject_expr_id = slicing_expr.subject;
 
        let from_expr_id = slicing_expr.from_index;
 
        let to_expr_id = slicing_expr.to_index;
 

	
 
        self.visit_expr(ctx, subject_expr_id)?;
 
        self.visit_expr(ctx, from_expr_id)?;
 
        self.visit_expr(ctx, to_expr_id)?;
 

	
 
        self.progress_slicing_expr(ctx, id)
 
    }
 

	
 
    fn visit_select_expr(&mut self, ctx: &mut Ctx, id: SelectExpressionId) -> VisitorResult {
 
        let upcast_id = id.upcast();
 
        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
 

	
 
        let select_expr = &ctx.heap[id];
 
        let subject_expr_id = select_expr.subject;
 

	
 
        self.visit_expr(ctx, subject_expr_id)?;
 

	
 
        self.progress_select_expr(ctx, id)
 
    }
 

	
 
    fn visit_array_expr(&mut self, ctx: &mut Ctx, id: ArrayExpressionId) -> VisitorResult {
 
        let upcast_id = id.upcast();
 
        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
 

	
 
        let array_expr = &ctx.heap[id];
 
        // TODO: @performance
 
        for element_id in array_expr.elements.clone().into_iter() {
 
            self.visit_expr(ctx, element_id)?;
 
        }
 

	
 
        self.progress_array_expr(ctx, id)
 
    }
 

	
 
    fn visit_constant_expr(&mut self, ctx: &mut Ctx, id: ConstantExpressionId) -> VisitorResult {
 
    fn visit_literal_expr(&mut self, ctx: &mut Ctx, id: LiteralExpressionId) -> VisitorResult {
 
        let upcast_id = id.upcast();
 
        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
 
        self.progress_constant_expr(ctx, id)
 
    }
 

	
 
    fn visit_call_expr(&mut self, ctx: &mut Ctx, id: CallExpressionId) -> VisitorResult {
 
        let upcast_id = id.upcast();
 
        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
 
        self.insert_initial_call_polymorph_data(ctx, id);
 

	
 
        // TODO: @performance
 
        let call_expr = &ctx.heap[id];
 
        for arg_expr_id in call_expr.arguments.clone() {
 
            self.visit_expr(ctx, arg_expr_id)?;
 
        }
 

	
 
        self.progress_call_expr(ctx, id)
 
    }
 

	
 
    fn visit_variable_expr(&mut self, ctx: &mut Ctx, id: VariableExpressionId) -> VisitorResult {
 
        let upcast_id = id.upcast();
 
        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
 

	
 
        let var_expr = &ctx.heap[id];
 
        debug_assert!(var_expr.declaration.is_some());
 
        let var_data = self.var_types.get_mut(var_expr.declaration.as_ref().unwrap()).unwrap();
 
        var_data.used_at.push(upcast_id);
 

	
 
        self.progress_variable_expr(ctx, id)
 
    }
 
}
 

	
 
macro_rules! debug_assert_expr_ids_unique_and_known {
 
    // Base case for a single expression ID
 
    ($resolver:ident, $id:ident) => {
 
        if cfg!(debug_assertions) {
 
            $resolver.expr_types.contains_key(&$id);
 
        }
 
    };
 
    // Base case for two expression IDs
 
    ($resolver:ident, $id1:ident, $id2:ident) => {
 
        debug_assert_ne!($id1, $id2);
 
        debug_assert_expr_ids_unique_and_known!($resolver, $id1);
 
        debug_assert_expr_ids_unique_and_known!($resolver, $id2);
 
    };
 
    // Generic case
 
    ($resolver:ident, $id1:ident, $id2:ident, $($tail:ident),+) => {
 
        debug_assert_ne!($id1, $id2);
 
        debug_assert_expr_ids_unique_and_known!($resolver, $id1);
 
        debug_assert_expr_ids_unique_and_known!($resolver, $id2, $($tail),+);
 
    };
 
}
 

	
 
macro_rules! debug_assert_ptrs_distinct {
 
    // Base case
 
    ($ptr1:ident, $ptr2:ident) => {
 
        debug_assert!(!std::ptr::eq($ptr1, $ptr2));
 
    };
 
    // Generic case
 
    ($ptr1:ident, $ptr2:ident, $($tail:ident),+) => {
 
        debug_assert_ptrs_distinct!($ptr1, $ptr2);
 
        debug_assert_ptrs_distinct!($ptr2, $($tail),+);
 
    };
 
}
 

	
 
impl TypeResolvingVisitor {
 
    fn resolve_types(&mut self, ctx: &mut Ctx, queue: &mut ResolveQueue) -> Result<(), ParseError2> {
 
        // Keep inferring until we can no longer make any progress
 
        while let Some(next_expr_id) = self.expr_queued.iter().next() {
 
            let next_expr_id = *next_expr_id;
 
            self.expr_queued.remove(&next_expr_id);
 
            self.progress_expr(ctx, next_expr_id)?;
 
        }
 

	
 
        // Should have inferred everything. Check for this and optionally
 
        // auto-infer the remaining types
 
        for (expr_id, expr_type) in self.expr_types.iter_mut() {
 
            if !expr_type.is_done {
 
                // Auto-infer numberlike/integerlike types to a regular int
 
                if expr_type.parts.len() == 1 && expr_type.parts[0] == InferenceTypePart::IntegerLike {
 
                    expr_type.parts[0] = InferenceTypePart::Int;
 
                } else {
 
                    let expr = &ctx.heap[*expr_id];
 
                    return Err(ParseError2::new_error(
 
                        &ctx.module.source, expr.position(),
 
                        &format!(
 
                            "Could not fully infer the type of this expression (got '{}')",
 
                            expr_type.display_name(&ctx.heap)
 
                        )
 
                    ))
 
                }
 
            }
 

	
 
            let concrete_type = ctx.heap[*expr_id].get_type_mut();
 
            expr_type.write_concrete_type(concrete_type);
 
        }
 

	
 
        // Check all things we need to monomorphize
 
        // TODO: Struct/enum/union monomorphization
 
        for (call_expr_id, extra_data) in self.extra_data.iter() {
 
            if extra_data.poly_vars.is_empty() { continue; }
 

	
 
            // Retrieve polymorph variable specification
 
            let mut monomorph_types = Vec::with_capacity(extra_data.poly_vars.len());
 
            for (poly_idx, poly_type) in extra_data.poly_vars.iter().enumerate() {
 
                if !poly_type.is_done {
 
                    // TODO: Single clean function for function signatures and polyvars.
 
                    // TODO: Better error message
 
                    let expr = &ctx.heap[*call_expr_id];
 
                    return Err(ParseError2::new_error(
 
                        &ctx.module.source, expr.position(),
 
                        &format!(
 
                            "Could not fully infer the type of polymorphic variable {} of this expression (got '{}')",
 
                            poly_idx, poly_type.display_name(&ctx.heap)
 
                        )
 
                    ))
 
                }
 

	
 
                let mut concrete_type = ConcreteType::default();
 
                poly_type.write_concrete_type(&mut concrete_type);
 
                monomorph_types.insert(poly_idx, concrete_type);
 
            }
 

	
 
            // Resolve to call expression's definition
 
            let call_expr = if let Expression::Call(call_expr) = &ctx.heap[*call_expr_id] {
 
                call_expr
 
            } else {
 
                todo!("implement different kinds of polymorph expressions");
 
            };
 

	
 
            // Add to type table if not yet typechecked
 
            if let Method::Symbolic(symbolic) = &call_expr.method {
 
                let definition_id = symbolic.definition.unwrap();
 
                if !ctx.types.has_monomorph(&definition_id, &monomorph_types) {
 
                    let root_id = ctx.types
 
                        .get_base_definition(&definition_id)
 
                        .unwrap()
 
                        .ast_root;
 

	
 
                    // Pre-emptively add the monomorph to the type table, but
 
                    // we still need to perform typechecking on it
 
                    ctx.types.add_monomorph(&definition_id, monomorph_types.clone());
 
                    queue.push(ResolveQueueElement {
 
                        root_id,
 
                        definition_id,
 
                        monomorph_types,
 
                    })
 
                }
 
            }
 
        }
 

	
 
        Ok(())
 
    }
 

	
 
    fn progress_expr(&mut self, ctx: &mut Ctx, id: ExpressionId) -> Result<(), ParseError2> {
 
        match &ctx.heap[id] {
 
            Expression::Assignment(expr) => {
 
                let id = expr.this;
 
                self.progress_assignment_expr(ctx, id)
 
            },
 
            Expression::Conditional(expr) => {
 
                let id = expr.this;
 
                self.progress_conditional_expr(ctx, id)
 
            },
 
            Expression::Binary(expr) => {
 
                let id = expr.this;
 
                self.progress_binary_expr(ctx, id)
 
            },
 
            Expression::Unary(expr) => {
 
                let id = expr.this;
 
                self.progress_unary_expr(ctx, id)
 
            },
 
            Expression::Indexing(expr) => {
 
                let id = expr.this;
 
                self.progress_indexing_expr(ctx, id)
 
            },
 
            Expression::Slicing(expr) => {
 
                let id = expr.this;
 
                self.progress_slicing_expr(ctx, id)
 
            },
 
            Expression::Select(expr) => {
 
                let id = expr.this;
 
                self.progress_select_expr(ctx, id)
 
            },
 
            Expression::Array(expr) => {
 
                let id = expr.this;
 
                self.progress_array_expr(ctx, id)
 
            },
 
            Expression::Constant(expr) => {
 
            Expression::Literal(expr) => {
 
                let id = expr.this;
 
                self.progress_constant_expr(ctx, id)
 
            },
 
            Expression::Call(expr) => {
 
                let id = expr.this;
 
                self.progress_call_expr(ctx, id)
 
            },
 
            Expression::Variable(expr) => {
 
                let id = expr.this;
 
                self.progress_variable_expr(ctx, id)
 
            }
 
        }
 
    }
 

	
 
    fn progress_assignment_expr(&mut self, ctx: &mut Ctx, id: AssignmentExpressionId) -> Result<(), ParseError2> {
 
        use AssignmentOperator as AO;
 

	
 
        // TODO: Assignable check
 
        let upcast_id = id.upcast();
 
        let expr = &ctx.heap[id];
 
        let arg1_expr_id = expr.left;
 
        let arg2_expr_id = expr.right;
 

	
 
        debug_log!("Assignment expr '{:?}': {}", expr.operation, upcast_id.index);
 
        debug_log!(" * Before:");
 
        debug_log!("   - Arg1 type: {}", self.expr_types.get(&arg1_expr_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Arg2 type: {}", self.expr_types.get(&arg2_expr_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr type: {}", self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        let progress_base = match expr.operation {
 
            AO::Set =>
 
                false,
 
            AO::Multiplied | AO::Divided | AO::Added | AO::Subtracted =>
 
                self.apply_forced_constraint(ctx, upcast_id, &NUMBERLIKE_TEMPLATE)?,
 
            AO::Remained | AO::ShiftedLeft | AO::ShiftedRight |
 
            AO::BitwiseAnded | AO::BitwiseXored | AO::BitwiseOred =>
 
                self.apply_forced_constraint(ctx, upcast_id, &INTEGERLIKE_TEMPLATE)?,
 
        };
 

	
 
        let (progress_expr, progress_arg1, progress_arg2) = self.apply_equal3_constraint(
 
            ctx, upcast_id, arg1_expr_id, arg2_expr_id, 0
 
        )?;
 

	
 
        debug_log!(" * After:");
 
        debug_log!("   - Arg1 type [{}]: {}", progress_arg1, self.expr_types.get(&arg1_expr_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Arg2 type [{}]: {}", progress_arg2, self.expr_types.get(&arg2_expr_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr type [{}]: {}", progress_base || progress_expr, self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 

	
 
        if progress_base || progress_expr { self.queue_expr_parent(ctx, upcast_id); }
 
        if progress_arg1 { self.queue_expr(arg1_expr_id); }
 
        if progress_arg2 { self.queue_expr(arg2_expr_id); }
 

	
 
        Ok(())
 
    }
 

	
 
    fn progress_conditional_expr(&mut self, ctx: &mut Ctx, id: ConditionalExpressionId) -> Result<(), ParseError2> {
 
        // Note: test expression type is already enforced
 
        let upcast_id = id.upcast();
 
        let expr = &ctx.heap[id];
 
        let arg1_expr_id = expr.true_expression;
 
        let arg2_expr_id = expr.false_expression;
 

	
 
        debug_log!("Conditional expr: {}", upcast_id.index);
 
        debug_log!(" * Before:");
 
        debug_log!("   - Arg1 type: {}", self.expr_types.get(&arg1_expr_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Arg2 type: {}", self.expr_types.get(&arg2_expr_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr type: {}", self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        let (progress_expr, progress_arg1, progress_arg2) = self.apply_equal3_constraint(
 
            ctx, upcast_id, arg1_expr_id, arg2_expr_id, 0
 
        )?;
 

	
 
        debug_log!(" * After:");
 
        debug_log!("   - Arg1 type [{}]: {}", progress_arg1, self.expr_types.get(&arg1_expr_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Arg2 type [{}]: {}", progress_arg2, self.expr_types.get(&arg2_expr_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr type [{}]: {}", progress_expr, self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
 
        if progress_arg1 { self.queue_expr(arg1_expr_id); }
 
        if progress_arg2 { self.queue_expr(arg2_expr_id); }
 

	
 
        Ok(())
 
    }
 

	
 
    fn progress_binary_expr(&mut self, ctx: &mut Ctx, id: BinaryExpressionId) -> Result<(), ParseError2> {
 
        // Note: our expression type might be fixed by our parent, but we still
 
        // need to make sure it matches the type associated with our operation.
 
        use BinaryOperator as BO;
 

	
 
        let upcast_id = id.upcast();
 
        let expr = &ctx.heap[id];
 
        let arg1_id = expr.left;
 
        let arg2_id = expr.right;
 

	
 
        debug_log!("Binary expr '{:?}': {}", expr.operation, upcast_id.index);
 
        debug_log!(" * Before:");
 
        debug_log!("   - Arg1 type: {}", self.expr_types.get(&arg1_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Arg2 type: {}", self.expr_types.get(&arg2_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr type: {}", self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        let (progress_expr, progress_arg1, progress_arg2) = match expr.operation {
 
            BO::Concatenate => {
 
                // Arguments may be arrays/slices, output is always an array
 
                let progress_expr = self.apply_forced_constraint(ctx, upcast_id, &ARRAY_TEMPLATE)?;
 
                let progress_arg1 = self.apply_forced_constraint(ctx, arg1_id, &ARRAYLIKE_TEMPLATE)?;
 
                let progress_arg2 = self.apply_forced_constraint(ctx, arg2_id, &ARRAYLIKE_TEMPLATE)?;
 

	
 
                // If they're all arraylike, then we want the subtype to match
 
                let (subtype_expr, subtype_arg1, subtype_arg2) =
 
                    self.apply_equal3_constraint(ctx, upcast_id, arg1_id, arg2_id, 1)?;
 

	
 
                (progress_expr || subtype_expr, progress_arg1 || subtype_arg1, progress_arg2 || subtype_arg2)
 
            },
 
            BO::LogicalOr | BO::LogicalAnd => {
 
                // Forced boolean on all
 
                let progress_expr = self.apply_forced_constraint(ctx, upcast_id, &BOOL_TEMPLATE)?;
 
                let progress_arg1 = self.apply_forced_constraint(ctx, arg1_id, &BOOL_TEMPLATE)?;
 
                let progress_arg2 = self.apply_forced_constraint(ctx, arg2_id, &BOOL_TEMPLATE)?;
 

	
 
                (progress_expr, progress_arg1, progress_arg2)
 
            },
 
            BO::BitwiseOr | BO::BitwiseXor | BO::BitwiseAnd | BO::Remainder | BO::ShiftLeft | BO::ShiftRight => {
 
                // All equal of integer type
 
                let progress_base = self.apply_forced_constraint(ctx, upcast_id, &INTEGERLIKE_TEMPLATE)?;
 
                let (progress_expr, progress_arg1, progress_arg2) =
 
                    self.apply_equal3_constraint(ctx, upcast_id, arg1_id, arg2_id, 0)?;
 

	
 
                (progress_base || progress_expr, progress_base || progress_arg1, progress_base || progress_arg2)
 
            },
 
            BO::Equality | BO::Inequality => {
 
                // Equal2 on args, forced boolean output
 
                let progress_expr = self.apply_forced_constraint(ctx, upcast_id, &BOOL_TEMPLATE)?;
 
                let (progress_arg1, progress_arg2) =
 
                    self.apply_equal2_constraint(ctx, upcast_id, arg1_id, 0, arg2_id, 0)?;
 

	
 
                (progress_expr, progress_arg1, progress_arg2)
 
            },
 
            BO::LessThan | BO::GreaterThan | BO::LessThanEqual | BO::GreaterThanEqual => {
 
                // Equal2 on args with numberlike type, forced boolean output
 
                let progress_expr = self.apply_forced_constraint(ctx, upcast_id, &BOOL_TEMPLATE)?;
 
                let progress_arg_base = self.apply_forced_constraint(ctx, arg1_id, &NUMBERLIKE_TEMPLATE)?;
 
                let (progress_arg1, progress_arg2) =
 
                    self.apply_equal2_constraint(ctx, upcast_id, arg1_id, 0, arg2_id, 0)?;
 

	
 
                (progress_expr, progress_arg_base || progress_arg1, progress_arg_base || progress_arg2)
 
            },
 
            BO::Add | BO::Subtract | BO::Multiply | BO::Divide => {
 
                // All equal of number type
 
                let progress_base = self.apply_forced_constraint(ctx, upcast_id, &NUMBERLIKE_TEMPLATE)?;
 
                let (progress_expr, progress_arg1, progress_arg2) =
 
                    self.apply_equal3_constraint(ctx, upcast_id, arg1_id, arg2_id, 0)?;
 

	
 
                (progress_base || progress_expr, progress_base || progress_arg1, progress_base || progress_arg2)
 
            },
 
        };
 

	
 
        debug_log!(" * After:");
 
        debug_log!("   - Arg1 type [{}]: {}", progress_arg1, self.expr_types.get(&arg1_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Arg2 type [{}]: {}", progress_arg2, self.expr_types.get(&arg2_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr type [{}]: {}", progress_expr, self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
 
        if progress_arg1 { self.queue_expr(arg1_id); }
 
        if progress_arg2 { self.queue_expr(arg2_id); }
 

	
 
        Ok(())
 
    }
 

	
 
    fn progress_unary_expr(&mut self, ctx: &mut Ctx, id: UnaryExpressionId) -> Result<(), ParseError2> {
 
        use UnaryOperation as UO;
 

	
 
        let upcast_id = id.upcast();
 
        let expr = &ctx.heap[id];
 
        let arg_id = expr.expression;
 

	
 
        debug_log!("Unary expr '{:?}': {}", expr.operation, upcast_id.index);
 
        debug_log!(" * Before:");
 
        debug_log!("   - Arg  type: {}", self.expr_types.get(&arg_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr type: {}", self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        let (progress_expr, progress_arg) = match expr.operation {
 
            UO::Positive | UO::Negative => {
 
                // Equal types of numeric class
 
                let progress_base = self.apply_forced_constraint(ctx, upcast_id, &NUMBERLIKE_TEMPLATE)?;
 
                let (progress_expr, progress_arg) =
 
                    self.apply_equal2_constraint(ctx, upcast_id, upcast_id, 0, arg_id, 0)?;
 

	
 
                (progress_base || progress_expr, progress_base || progress_arg)
 
            },
 
            UO::BitwiseNot | UO::PreIncrement | UO::PreDecrement | UO::PostIncrement | UO::PostDecrement => {
 
                // Equal types of integer class
 
                let progress_base = self.apply_forced_constraint(ctx, upcast_id, &INTEGERLIKE_TEMPLATE)?;
 
                let (progress_expr, progress_arg) =
 
                    self.apply_equal2_constraint(ctx, upcast_id, upcast_id, 0, arg_id, 0)?;
 

	
 
                (progress_base || progress_expr, progress_base || progress_arg)
 
            },
 
            UO::LogicalNot => {
 
                // Both booleans
 
                let progress_expr = self.apply_forced_constraint(ctx, upcast_id, &BOOL_TEMPLATE)?;
 
                let progress_arg = self.apply_forced_constraint(ctx, upcast_id, &BOOL_TEMPLATE)?;
 
                (progress_expr, progress_arg)
 
            }
 
        };
 

	
 
        debug_log!(" * After:");
 
        debug_log!("   - Arg  type [{}]: {}", progress_arg, self.expr_types.get(&arg_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr type [{}]: {}", progress_expr, self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
 
        if progress_arg { self.queue_expr(arg_id); }
 

	
 
        Ok(())
 
    }
 

	
 
    fn progress_indexing_expr(&mut self, ctx: &mut Ctx, id: IndexingExpressionId) -> Result<(), ParseError2> {
 
        let upcast_id = id.upcast();
 
        let expr = &ctx.heap[id];
 
        let subject_id = expr.subject;
 
        let index_id = expr.index;
 

	
 
        debug_log!("Indexing expr: {}", upcast_id.index);
 
        debug_log!(" * Before:");
 
        debug_log!("   - Subject type: {}", self.expr_types.get(&subject_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Index   type: {}", self.expr_types.get(&index_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr    type: {}", self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        // Make sure subject is arraylike and index is integerlike
 
        let progress_subject_base = self.apply_forced_constraint(ctx, subject_id, &ARRAYLIKE_TEMPLATE)?;
 
        let progress_index = self.apply_forced_constraint(ctx, index_id, &INTEGERLIKE_TEMPLATE)?;
 

	
 
        // Make sure if output is of T then subject is Array<T>
 
        let (progress_expr, progress_subject) =
 
            self.apply_equal2_constraint(ctx, upcast_id, upcast_id, 0, subject_id, 1)?;
 

	
 
        debug_log!(" * After:");
 
        debug_log!("   - Subject type [{}]: {}", progress_subject_base || progress_subject, self.expr_types.get(&subject_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Index   type [{}]: {}", progress_index, self.expr_types.get(&index_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr    type [{}]: {}", progress_expr, self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
 
        if progress_subject_base || progress_subject { self.queue_expr(subject_id); }
 
        if progress_index { self.queue_expr(index_id); }
 

	
 
        Ok(())
 
    }
 

	
 
    fn progress_slicing_expr(&mut self, ctx: &mut Ctx, id: SlicingExpressionId) -> Result<(), ParseError2> {
 
        let upcast_id = id.upcast();
 
        let expr = &ctx.heap[id];
 
        let subject_id = expr.subject;
 
        let from_id = expr.from_index;
 
        let to_id = expr.to_index;
 

	
 
        debug_log!("Slicing expr: {}", upcast_id.index);
 
        debug_log!(" * Before:");
 
        debug_log!("   - Subject type: {}", self.expr_types.get(&subject_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - FromIdx type: {}", self.expr_types.get(&from_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - ToIdx   type: {}", self.expr_types.get(&to_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr    type: {}", self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        // Make sure subject is arraylike and indices are of equal integerlike
 
        let progress_subject_base = self.apply_forced_constraint(ctx, subject_id, &ARRAYLIKE_TEMPLATE)?;
 
        let progress_idx_base = self.apply_forced_constraint(ctx, from_id, &INTEGERLIKE_TEMPLATE)?;
 
        let (progress_from, progress_to) = self.apply_equal2_constraint(ctx, upcast_id, from_id, 0, to_id, 0)?;
 

	
 
        // Make sure if output is of T then subject is Array<T>
 
        let (progress_expr, progress_subject) =
 
            self.apply_equal2_constraint(ctx, upcast_id, upcast_id, 0, subject_id, 1)?;
 

	
 

	
 
        debug_log!(" * After:");
 
        debug_log!("   - Subject type [{}]: {}", progress_subject_base || progress_subject, self.expr_types.get(&subject_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - FromIdx type [{}]: {}", progress_idx_base || progress_from, self.expr_types.get(&from_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - ToIdx   type [{}]: {}", progress_idx_base || progress_to, self.expr_types.get(&to_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr    type [{}]: {}", progress_expr, self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
 
        if progress_subject_base || progress_subject { self.queue_expr(subject_id); }
 
        if progress_idx_base || progress_from { self.queue_expr(from_id); }
 
        if progress_idx_base || progress_to { self.queue_expr(to_id); }
 

	
 
        Ok(())
 
    }
 

	
 
    fn progress_select_expr(&mut self, ctx: &mut Ctx, id: SelectExpressionId) -> Result<(), ParseError2> {
 
        let upcast_id = id.upcast();
 
        let expr = &ctx.heap[id];
 
        let subject_id = expr.subject;
 

	
 
        debug_log!("Select expr: {}", upcast_id.index);
 
        debug_log!(" * Before:");
 
        debug_log!("   - Subject type: {}", self.expr_types.get(&subject_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr    type: {}", self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        let (progress_subject, progress_expr) = match &expr.field {
 
            Field::Length => {
 
                let progress_subject = self.apply_forced_constraint(ctx, subject_id, &ARRAYLIKE_TEMPLATE)?;
 
                let progress_expr = self.apply_forced_constraint(ctx, upcast_id, &INTEGERLIKE_TEMPLATE)?;
 
                (progress_subject, progress_expr)
 
            },
 
            Field::Symbolic(_field) => {
 
                todo!("implement select expr for symbolic fields");
 
            }
 
        };
 

	
 
        debug_log!(" * After:");
 
        debug_log!("   - Subject type [{}]: {}", progress_subject, self.expr_types.get(&subject_id).unwrap().display_name(&ctx.heap));
 
        debug_log!("   - Expr    type [{}]: {}", progress_expr, self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        if progress_subject { self.queue_expr(subject_id); }
 
        if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
 

	
 
        Ok(())
 
    }
 

	
 
    fn progress_array_expr(&mut self, ctx: &mut Ctx, id: ArrayExpressionId) -> Result<(), ParseError2> {
 
        let upcast_id = id.upcast();
 
        let expr = &ctx.heap[id];
 
        let expr_elements = expr.elements.clone(); // TODO: @performance
 

	
 
        debug_log!("Array expr ({} elements): {}", expr_elements.len(), upcast_id.index);
 
        debug_log!(" * Before:");
 
        debug_log!("   - Expr type: {}", self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        // All elements should have an equal type
 
        let progress = self.apply_equal_n_constraint(ctx, upcast_id, &expr_elements)?;
 
        let mut any_progress = false;
 
        for (progress_arg, arg_id) in progress.iter().zip(expr_elements.iter()) {
 
            if *progress_arg {
 
                any_progress = true;
 
                self.queue_expr(*arg_id);
 
            }
 
        }
 

	
 
        // And the output should be an array of the element types
 
        let mut expr_progress = self.apply_forced_constraint(ctx, upcast_id, &ARRAY_TEMPLATE)?;
 
        if !expr_elements.is_empty() {
 
            let first_arg_id = expr_elements[0];
 
            let (inner_expr_progress, arg_progress) = self.apply_equal2_constraint(
 
                ctx, upcast_id, upcast_id, 1, first_arg_id, 0
 
            )?;
 

	
 
            expr_progress = expr_progress || inner_expr_progress;
 

	
 
            // Note that if the array type progressed the type of the arguments,
 
            // then we should enqueue this progression function again
 
            // TODO: @fix Make apply_equal_n accept a start idx as well
 
            if arg_progress { self.queue_expr(upcast_id); }
 
        }
 

	
 
        debug_log!(" * After:");
 
        debug_log!("   - Expr type [{}]: {}", expr_progress, self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        if expr_progress { self.queue_expr_parent(ctx, upcast_id); }
 

	
 
        Ok(())
 
    }
 

	
 
    fn progress_constant_expr(&mut self, ctx: &mut Ctx, id: ConstantExpressionId) -> Result<(), ParseError2> {
 
    fn progress_constant_expr(&mut self, ctx: &mut Ctx, id: LiteralExpressionId) -> Result<(), ParseError2> {
 
        let upcast_id = id.upcast();
 
        let expr = &ctx.heap[id];
 
        let template = match &expr.value {
 
            Constant::Null => &MESSAGE_TEMPLATE[..],
 
            Constant::Integer(_) => &INTEGERLIKE_TEMPLATE[..],
 
            Constant::True | Constant::False => &BOOL_TEMPLATE[..],
 
            Constant::Character(_) => todo!("character literals")
 
            Literal::Null => &MESSAGE_TEMPLATE[..],
 
            Literal::Integer(_) => &INTEGERLIKE_TEMPLATE[..],
 
            Literal::True | Literal::False => &BOOL_TEMPLATE[..],
 
            Literal::Character(_) => todo!("character literals")
 
        };
 

	
 
        let progress = self.apply_forced_constraint(ctx, upcast_id, template)?;
 
        if progress { self.queue_expr_parent(ctx, upcast_id); }
 

	
 
        Ok(())
 
    }
 

	
 
    // TODO: @cleanup, see how this can be cleaned up once I implement
 
    //  polymorphic struct/enum/union literals. These likely follow the same
 
    //  pattern as here.
 
    fn progress_call_expr(&mut self, ctx: &mut Ctx, id: CallExpressionId) -> Result<(), ParseError2> {
 
        let upcast_id = id.upcast();
 
        let expr = &ctx.heap[id];
 
        let extra = self.extra_data.get_mut(&upcast_id).unwrap();
 

	
 
        debug_log!("Call expr '{}': {}", match &expr.method {
 
            Method::Create => String::from("create"),
 
            Method::Fires => String::from("fires"),
 
            Method::Get => String::from("get"),
 
            Method::Put => String::from("put"),
 
            Method::Symbolic(method) => String::from_utf8_lossy(&method.identifier.value).to_string()
 
        },upcast_id.index);
 
        debug_log!(" * Before:");
 
        debug_log!("   - Expr type: {}", self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 
        debug_log!(" * During (inferring types from arguments and return type):");
 

	
 
        // Check if we can make progress using the arguments and/or return types
 
        // while keeping track of the polyvars we've extended
 
        let mut poly_progress = HashSet::new();
 
        debug_assert_eq!(extra.embedded.len(), expr.arguments.len());
 
        let mut poly_infer_error = false;
 

	
 
        for (arg_idx, arg_id) in expr.arguments.clone().into_iter().enumerate() {
 
            let signature_type = &mut extra.embedded[arg_idx];
 
            let argument_type: *mut _ = self.expr_types.get_mut(&arg_id).unwrap();
 
            let (progress_sig, progress_arg) = Self::apply_equal2_signature_constraint(
 
                ctx, upcast_id, Some(arg_id), signature_type, 0, argument_type, 0
 
            )?;
 

	
 
            debug_log!("   - Arg {} type | sig: {}, arg: {}", arg_idx, signature_type.display_name(&ctx.heap), unsafe{&*argument_type}.display_name(&ctx.heap));
 

	
 
            if progress_sig {
 
                // Progressed signature, so also apply inference to the 
 
                // polymorph types using the markers 
 
                debug_assert!(signature_type.has_body_marker, "progress on signature argument type without markers");
 
                for (poly_idx, poly_section) in signature_type.body_marker_iter() {
 
                    let polymorph_type = &mut extra.poly_vars[poly_idx];
 
                    match Self::apply_forced_constraint_types(
 
                        polymorph_type, 0, poly_section, 0
 
                    ) {
 
                        Ok(true) => { poly_progress.insert(poly_idx); },
 
                        Ok(false) => {},
 
                        Err(()) => { poly_infer_error = true; }
 
                    }
 

	
 
                    debug_log!("   - Poly {} type | sig: {}, arg: {}", poly_idx, polymorph_type.display_name(&ctx.heap), InferenceType::partial_display_name(&ctx.heap, poly_section));
 
                }
 
            }
 
            if progress_arg {
 
                // Progressed argument expression
 
                self.expr_queued.insert(arg_id);
 
            }
 
        }
 

	
 
        // Do the same for the return type
 
        let signature_type = &mut extra.returned;
 
        let expr_type: *mut _ = self.expr_types.get_mut(&upcast_id).unwrap();
 
        let (progress_sig, progress_expr) = Self::apply_equal2_signature_constraint(
 
            ctx, upcast_id, None, signature_type, 0, expr_type, 0
 
        )?;
 

	
 
        debug_log!("   - Ret type | sig: {}, arg: {}", signature_type.display_name(&ctx.heap), unsafe{&*expr_type}.display_name(&ctx.heap));
 

	
 
        if progress_sig {
 
            // As above: apply inference to polyargs as well
 
            debug_assert!(signature_type.has_body_marker, "progress on signature return type without markers");
 
            for (poly_idx, poly_section) in signature_type.body_marker_iter() {
 
                let polymorph_type = &mut extra.poly_vars[poly_idx];
 
                match Self::apply_forced_constraint_types(
 
                    polymorph_type, 0, poly_section, 0
 
                ) {
 
                    Ok(true) => { poly_progress.insert(poly_idx); },
 
                    Ok(false) => {},
 
                    Err(()) => { poly_infer_error = true; }
 
                }
 
                debug_log!("   - Poly {} type | sig: {}, arg: {}", poly_idx, polymorph_type.display_name(&ctx.heap), InferenceType::partial_display_name(&ctx.heap, poly_section));
 
            }
 
        }
 
        if progress_expr {
 
            if let Some(parent_id) = ctx.heap[upcast_id].parent_expr_id() {
 
                self.expr_queued.insert(parent_id);
 
            }
 
        }
 

	
 
        // If we had an error in the polymorphic variable's inference, then we
 
        // need to provide a human readable error: find a pair of inference
 
        // types in the arguments/return type that do not agree on the
 
        // polymorphic variable's type
 
        if poly_infer_error { return Err(self.construct_poly_arg_error(ctx, id)) }
 

	
 
        // If we did not have an error in the polymorph inference above, then
 
        // reapplying the polymorph type to each argument type and the return
 
        // type should always succeed.
 
        debug_log!(" * During (reinferring from progress polyvars):");
 
        // TODO: @performance If the algorithm is changed to be more "on demand
 
        //  argument re-evaluation", instead of "all-argument re-evaluation",
 
        //  then this is no longer true
 
        for poly_idx in poly_progress.into_iter() {
 
            // For each polymorphic argument: first extend the signature type,
 
            // then reapply the equal2 constraint to the expressions
 
            let poly_type = &extra.poly_vars[poly_idx];
 
            for (arg_idx, sig_type) in extra.embedded.iter_mut().enumerate() {
 
                let mut seek_idx = 0;
 
                let mut modified_sig = false;
 
                while let Some((start_idx, end_idx)) = sig_type.find_subtree_idx_for_part(
 
                    InferenceTypePart::MarkerBody(poly_idx), seek_idx
 
                ) {
 
                    let modified_at_marker = Self::apply_forced_constraint_types(
 
                        sig_type, start_idx, &poly_type.parts, 0
 
                    ).unwrap();
 
                    modified_sig = modified_sig || modified_at_marker;
 
                    seek_idx = end_idx;
 
                }
 

	
 
                if !modified_sig {
 
                    debug_log!("   - Poly {} | Arg {} type | signature has not changed", poly_idx, arg_idx);
 
                    continue;
 
                }
 

	
 
                // Part of signature was modified, so update expression used as
 
                // argument as well
 
                let arg_expr_id = expr.arguments[arg_idx];
 
                let arg_type: *mut _ = self.expr_types.get_mut(&arg_expr_id).unwrap();
 
                let (_, progress_arg) = Self::apply_equal2_signature_constraint(
 
                    ctx, arg_expr_id, Some(arg_expr_id), sig_type, 0, arg_type, 0
 
                ).expect("no inference error at argument type");
 
                if progress_arg { self.expr_queued.insert(arg_expr_id); }
 
                debug_log!("   - Poly {} | Arg {} type | sig: {}, arg: {}", poly_idx, arg_idx, sig_type.display_name(&ctx.heap), unsafe{&*arg_type}.display_name(&ctx.heap));
 
            }
 

	
 
            // Again: do the same for the return type
 
            let sig_type = &mut extra.returned;
 
            let mut seek_idx = 0;
 
            let mut modified_sig = false;
 
            while let Some((start_idx, end_idx)) = sig_type.find_subtree_idx_for_part(
 
                InferenceTypePart::MarkerBody(poly_idx), seek_idx
 
            ) {
 
                let modified_at_marker = Self::apply_forced_constraint_types(
 
                    sig_type, start_idx, &poly_type.parts, 0
 
                ).unwrap();
 
                modified_sig = modified_sig || modified_at_marker;
 
                seek_idx = end_idx;
 
            }
 

	
 
            if modified_sig {
 
                let ret_type = self.expr_types.get_mut(&upcast_id).unwrap();
 
                let (_, progress_ret) = Self::apply_equal2_signature_constraint(
 
                    ctx, upcast_id, None, sig_type, 0, ret_type, 0
 
                ).expect("no inference error at return type");
 
                if progress_ret {
 
                    if let Some(parent_id) = ctx.heap[upcast_id].parent_expr_id() {
 
                        self.expr_queued.insert(parent_id);
 
                    }
 
                }
 
                debug_log!("   - Poly {} | Ret type | sig: {}, arg: {}", poly_idx, sig_type.display_name(&ctx.heap), ret_type.display_name(&ctx.heap));
 
            } else {
 
                debug_log!("   - Poly {} | Ret type | signature has not changed", poly_idx);
 
            }
 
        }
 

	
 
        debug_log!(" * After:");
 
        debug_log!("   - Expr type: {}", self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        Ok(())
 
    }
 

	
 
    fn progress_variable_expr(&mut self, ctx: &mut Ctx, id: VariableExpressionId) -> Result<(), ParseError2> {
 
        let upcast_id = id.upcast();
 
        let var_expr = &ctx.heap[id];
 
        let var_id = var_expr.declaration.unwrap();
 

	
 
        debug_log!("Variable expr '{}': {}", &String::from_utf8_lossy(&ctx.heap[var_id].identifier().value), upcast_id.index);
 
        debug_log!(" * Before:");
 
        debug_log!("   - Var  type: {}", self.var_types.get(&var_id).unwrap().var_type.display_name(&ctx.heap));
 
        debug_log!("   - Expr type: {}", self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 
        // Retrieve shared variable type and expression type and apply inference
 
        let var_data = self.var_types.get_mut(&var_id).unwrap();
 
        let expr_type = self.expr_types.get_mut(&upcast_id).unwrap();
 

	
 
        let infer_res = unsafe{ InferenceType::infer_subtrees_for_both_types(
 
            &mut var_data.var_type as *mut _, 0, expr_type, 0
 
        ) };
 
        if infer_res == DualInferenceResult::Incompatible {
 
            let var_decl = &ctx.heap[var_id];
 
            return Err(ParseError2::new_error(
 
                &ctx.module.source, var_decl.position(),
 
                &format!(
 
                    "Conflicting types for this variable, previously assigned the type '{}'",
 
                    var_data.var_type.display_name(&ctx.heap)
 
                )
 
            ).with_postfixed_info(
 
                &ctx.module.source, var_expr.position,
 
                &format!(
 
                    "But inferred to have incompatible type '{}' here",
 
                    expr_type.display_name(&ctx.heap)
 
                )
 
            ))
 
        }
 

	
 
        let progress_var = infer_res.modified_lhs();
 
        let progress_expr = infer_res.modified_rhs();
 

	
 
        if progress_var {
 
            // Let other variable expressions using this type progress as well
 
            for other_expr in var_data.used_at.iter() {
 
                if *other_expr != upcast_id {
 
                    self.expr_queued.insert(*other_expr);
 
                }
 
            }
 

	
 
            // Let a linked port know that our type has updated
 
            if let Some(linked_id) = var_data.linked_var {
 
                // Only perform one-way inference to prevent updating our type, this
 
                // would lead to an inconsistency
 
                let var_type: *mut _ = &mut var_data.var_type;
 
                let mut link_data = self.var_types.get_mut(&linked_id).unwrap();
 

	
 
                debug_assert!(
 
                    unsafe{&*var_type}.parts[0] == InferenceTypePart::Input ||
 
                    unsafe{&*var_type}.parts[0] == InferenceTypePart::Output
 
                );
 
                debug_assert!(
 
                    link_data.var_type.parts[0] == InferenceTypePart::Input ||
 
                    link_data.var_type.parts[0] == InferenceTypePart::Output
 
                );
 
                match InferenceType::infer_subtree_for_single_type(&mut link_data.var_type, 1, &unsafe{&*var_type}.parts, 1) {
 
                    SingleInferenceResult::Modified => {
 
                        for other_expr in &link_data.used_at {
 
                            self.expr_queued.insert(*other_expr);
 
                        }
 
                    },
 
                    SingleInferenceResult::Unmodified => {},
 
                    SingleInferenceResult::Incompatible => {
 
                        let var_data = self.var_types.get(&var_id).unwrap();
 
                        let link_data = self.var_types.get(&linked_id).unwrap();
 
                        let var_decl = &ctx.heap[var_id];
 
                        let link_decl = &ctx.heap[linked_id];
 

	
 
                        return Err(ParseError2::new_error(
 
                            &ctx.module.source, var_decl.position(),
 
                            &format!(
 
                                "Conflicting types for this variable, assigned the type '{}'",
 
                                var_data.var_type.display_name(&ctx.heap)
 
                            )
 
                        ).with_postfixed_info(
 
                            &ctx.module.source, link_decl.position(),
 
                            &format!(
 
                                "Because it is incompatible with this variable, assigned the type '{}'",
 
                                link_data.var_type.display_name(&ctx.heap)
 
                            )
 
                        ));
 
                    }
 
                }
 
            }
 
        }
 
        if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
 

	
 
        debug_log!(" * After:");
 
        debug_log!("   - Var  type [{}]: {}", progress_var, self.var_types.get(&var_id).unwrap().var_type.display_name(&ctx.heap));
 
        debug_log!("   - Expr type [{}]: {}", progress_expr, self.expr_types.get(&upcast_id).unwrap().display_name(&ctx.heap));
 

	
 

	
 
        Ok(())
 
    }
 

	
 
    fn queue_expr_parent(&mut self, ctx: &Ctx, expr_id: ExpressionId) {
 
        if let ExpressionParent::Expression(parent_expr_id, _) = &ctx.heap[expr_id].parent() {
 
            self.expr_queued.insert(*parent_expr_id);
 
        }
 
    }
 

	
 
    fn queue_expr(&mut self, expr_id: ExpressionId) {
 
        self.expr_queued.insert(expr_id);
 
    }
 

	
 
    /// Applies a forced type constraint: the type associated with the supplied
 
    /// expression will be molded into the provided "template". The template may
 
    /// be fully specified (e.g. a bool) or contain "inference" variables (e.g.
 
    /// an array of T)
 
    fn apply_forced_constraint(
 
        &mut self, ctx: &mut Ctx, expr_id: ExpressionId, template: &[InferenceTypePart]
 
    ) -> Result<bool, ParseError2> {
 
        debug_assert_expr_ids_unique_and_known!(self, expr_id);
 
        let expr_type = self.expr_types.get_mut(&expr_id).unwrap();
 
        match InferenceType::infer_subtree_for_single_type(expr_type, 0, template, 0) {
 
            SingleInferenceResult::Modified => Ok(true),
 
            SingleInferenceResult::Unmodified => Ok(false),
 
            SingleInferenceResult::Incompatible => Err(
 
                self.construct_template_type_error(ctx, expr_id, template)
 
            )
 
        }
 
    }
 

	
 
    fn apply_forced_constraint_types(
 
        to_infer: *mut InferenceType, to_infer_start_idx: usize,
 
        template: &[InferenceTypePart], template_start_idx: usize
 
    ) -> Result<bool, ()> {
 
        match InferenceType::infer_subtree_for_single_type(
 
            unsafe{ &mut *to_infer }, to_infer_start_idx,
 
            template, template_start_idx
 
        ) {
 
            SingleInferenceResult::Modified => Ok(true),
 
            SingleInferenceResult::Unmodified => Ok(false),
 
            SingleInferenceResult::Incompatible => Err(()),
 
        }
 
    }
 

	
 
    /// Applies a type constraint that expects the two provided types to be
 
    /// equal. We attempt to make progress in inferring the types. If the call
 
    /// is successful then the composition of all types are made equal.
 
    /// The "parent" `expr_id` is provided to construct errors.
 
    fn apply_equal2_constraint(
 
        &mut self, ctx: &Ctx, expr_id: ExpressionId,
 
        arg1_id: ExpressionId, arg1_start_idx: usize,
 
        arg2_id: ExpressionId, arg2_start_idx: usize
 
    ) -> Result<(bool, bool), ParseError2> {
 
        debug_assert_expr_ids_unique_and_known!(self, arg1_id, arg2_id);
 
        let arg1_type: *mut _ = self.expr_types.get_mut(&arg1_id).unwrap();
 
        let arg2_type: *mut _ = self.expr_types.get_mut(&arg2_id).unwrap();
 

	
 
        let infer_res = unsafe{ InferenceType::infer_subtrees_for_both_types(
 
            arg1_type, arg1_start_idx,
 
            arg2_type, arg2_start_idx
 
        ) };
 
        if infer_res == DualInferenceResult::Incompatible {
 
            return Err(self.construct_arg_type_error(ctx, expr_id, arg1_id, arg2_id));
 
        }
 

	
 
        Ok((infer_res.modified_lhs(), infer_res.modified_rhs()))
 
    }
 

	
 
    fn apply_equal2_signature_constraint(
 
        ctx: &Ctx, outer_expr_id: ExpressionId, expr_id: Option<ExpressionId>,
 
        signature_type: *mut InferenceType, signature_start_idx: usize,
 
        expression_type: *mut InferenceType, expression_start_idx: usize
 
    ) -> Result<(bool, bool), ParseError2> {
 
        debug_assert_ptrs_distinct!(signature_type, expression_type);
 
        let infer_res = unsafe { 
 
            InferenceType::infer_subtrees_for_both_types(
 
                signature_type, signature_start_idx,
 
                expression_type, expression_start_idx
 
            ) 
 
        };
 

	
 
        if infer_res == DualInferenceResult::Incompatible {
 
            // TODO: Check if I still need to use this
 
            let outer_position = ctx.heap[outer_expr_id].position();
 
            let (position_name, position) = match expr_id {
 
                Some(expr_id) => ("argument's", ctx.heap[expr_id].position()),
 
                None => ("return type's", outer_position)
 
            };
 
            let (signature_display_type, expression_display_type) = unsafe { (
 
                (&*signature_type).display_name(&ctx.heap),
 
                (&*expression_type).display_name(&ctx.heap)
 
            ) };
 

	
 
            return Err(ParseError2::new_error(
 
                &ctx.module.source, outer_position,
 
                "Failed to fully resolve the types of this expression"
 
            ).with_postfixed_info(
 
                &ctx.module.source, position,
 
                &format!(
 
                    "Because the {} signature has been resolved to '{}', but the expression has been resolved to '{}'",
 
                    position_name, signature_display_type, expression_display_type
 
                )
 
            ));
 
        }
 

	
 
        Ok((infer_res.modified_lhs(), infer_res.modified_rhs()))
 
    }
 

	
 
    /// Applies a type constraint that expects all three provided types to be
 
    /// equal. In case we can make progress in inferring the types then we
 
    /// attempt to do so. If the call is successful then the composition of all
 
    /// types is made equal.
 
    fn apply_equal3_constraint(
 
        &mut self, ctx: &Ctx, expr_id: ExpressionId,
 
        arg1_id: ExpressionId, arg2_id: ExpressionId,
 
        start_idx: usize
 
    ) -> Result<(bool, bool, bool), ParseError2> {
 
        // Safety: all expression IDs are always distinct, and we do not modify
 
        //  the container
 
        debug_assert_expr_ids_unique_and_known!(self, expr_id, arg1_id, arg2_id);
 
        let expr_type: *mut _ = self.expr_types.get_mut(&expr_id).unwrap();
 
        let arg1_type: *mut _ = self.expr_types.get_mut(&arg1_id).unwrap();
 
        let arg2_type: *mut _ = self.expr_types.get_mut(&arg2_id).unwrap();
 

	
 
        let expr_res = unsafe{
 
            InferenceType::infer_subtrees_for_both_types(expr_type, start_idx, arg1_type, start_idx)
 
        };
 
        if expr_res == DualInferenceResult::Incompatible {
 
            return Err(self.construct_expr_type_error(ctx, expr_id, arg1_id));
 
        }
 

	
 
        let args_res = unsafe{
 
            InferenceType::infer_subtrees_for_both_types(arg1_type, start_idx, arg2_type, start_idx) };
 
        if args_res == DualInferenceResult::Incompatible {
 
            return Err(self.construct_arg_type_error(ctx, expr_id, arg1_id, arg2_id));
 
        }
 

	
 
        // If all types are compatible, but the second call caused the arg1_type
 
        // to be expanded, then we must also assign this to expr_type.
 
        let mut progress_expr = expr_res.modified_lhs();
 
        let mut progress_arg1 = expr_res.modified_rhs();
 
        let progress_arg2 = args_res.modified_rhs();
 

	
 
        if args_res.modified_lhs() { 
 
            unsafe {
 
                let end_idx = InferenceType::find_subtree_end_idx(&(*arg2_type).parts, start_idx);
 
                let subtree = &((*arg2_type).parts[start_idx..end_idx]);
 
                (*expr_type).replace_subtree(start_idx, subtree);
 
            }
 
            progress_expr = true;
 
            progress_arg1 = true;
 
        }
 

	
 
        Ok((progress_expr, progress_arg1, progress_arg2))
 
    }
 

	
 
    // TODO: @optimize Since we only deal with a single type this might be done
 
    //  a lot more efficiently, methinks (disregarding the allocations here)
 
    fn apply_equal_n_constraint(
 
        &mut self, ctx: &Ctx, expr_id: ExpressionId, args: &[ExpressionId],
 
    ) -> Result<Vec<bool>, ParseError2> {
 
        // Early exit
 
        match args.len() {
 
            0 => return Ok(vec!()),         // nothing to progress
 
            1 => return Ok(vec![false]),    // only one type, so nothing to infer
 
            _ => {}
 
        }
 

	
 
        let mut progress = Vec::new();
 
        progress.resize(args.len(), false);
 

	
 
        // Do pairwise inference, keep track of the last entry we made progress
 
        // on. Once done we need to update everything to the most-inferred type.
 
        let mut arg_iter = args.iter();
 
        let mut last_arg_id = *arg_iter.next().unwrap();
 
        let mut last_lhs_progressed = 0;
 
        let mut lhs_arg_idx = 0;
 

	
 
        while let Some(next_arg_id) = arg_iter.next() {
 
            let arg1_type: *mut _ = self.expr_types.get_mut(&last_arg_id).unwrap();
 
            let arg2_type: *mut _ = self.expr_types.get_mut(next_arg_id).unwrap();
 

	
 
            let res = unsafe {
 
                InferenceType::infer_subtrees_for_both_types(arg1_type, 0, arg2_type, 0)
 
            };
 

	
 
            if res == DualInferenceResult::Incompatible {
 
                return Err(self.construct_arg_type_error(ctx, expr_id, last_arg_id, *next_arg_id));
 
            }
 

	
 
            if res.modified_lhs() {
 
                // We re-inferred something on the left hand side, so everything
 
                // up until now should be re-inferred.
 
                progress[lhs_arg_idx] = true;
 
                last_lhs_progressed = lhs_arg_idx;
 
            }
 
            progress[lhs_arg_idx + 1] = res.modified_rhs();
 

	
 
            last_arg_id = *next_arg_id;
 
            lhs_arg_idx += 1;
 
        }
 

	
 
        // Re-infer everything. Note that we do not need to re-infer the type
 
        // exactly at `last_lhs_progressed`, but only everything up to it.
 
        let last_type: *mut _ = self.expr_types.get_mut(args.last().unwrap()).unwrap();
 
        for arg_idx in 0..last_lhs_progressed {
 
            let arg_type: *mut _ = self.expr_types.get_mut(&args[arg_idx]).unwrap();
 
            unsafe{
 
                (*arg_type).replace_subtree(0, &(*last_type).parts);
 
            }
 
            progress[arg_idx] = true;
 
        }
 

	
 
        Ok(progress)
 
    }
 

	
 
    /// Determines the `InferenceType` for the expression based on the
 
    /// expression parent. Note that if the parent is another expression, we do
 
    /// not take special action, instead we let parent expressions fix the type
 
    /// of subexpressions before they have a chance to call this function.
 
    /// Hence: if the expression type is already set, this function doesn't do
 
    /// anything.
 
    fn insert_initial_expr_inference_type(
 
        &mut self, ctx: &mut Ctx, expr_id: ExpressionId
 
    ) -> Result<(), ParseError2> {
 
        use ExpressionParent as EP;
 
        use InferenceTypePart as ITP;
 

	
 
        let expr = &ctx.heap[expr_id];
 
        let inference_type = match expr.parent() {
 
            EP::None =>
 
                // Should have been set by linker
 
                unreachable!(),
 
            EP::ExpressionStmt(_) | EP::Expression(_, _) =>
 
                // Determined during type inference
 
                InferenceType::new(false, false, vec![ITP::Unknown]),
 
            EP::If(_) | EP::While(_) | EP::Assert(_) =>
 
                // Must be a boolean
 
                InferenceType::new(false, true, vec![ITP::Bool]),
 
            EP::Return(_) =>
 
                // Must match the return type of the function
 
                if let DefinitionType::Function(func_id) = self.definition_type {
 
                    let return_parser_type_id = ctx.heap[func_id].return_type;
 
                    self.determine_inference_type_from_parser_type(ctx, return_parser_type_id, true)
 
                } else {
 
                    // Cannot happen: definition always set upon body traversal
 
                    // and "return" calls in components are illegal.
 
                    unreachable!();
 
                },
 
            EP::New(_) =>
 
                // Must be a component call, which we assign a "Void" return
 
                // type
 
                InferenceType::new(false, true, vec![ITP::Void]),
 
        };
 

	
 
        match self.expr_types.entry(expr_id) {
 
            Entry::Vacant(vacant) => {
 
                vacant.insert(inference_type);
 
            },
 
            Entry::Occupied(mut preexisting) => {
 
                // We already have an entry, this happens if our parent fixed
 
                // our type (e.g. we're used in a conditional expression's test)
 
                // but we have a different type.
 
                // TODO: Is this ever called? Seems like it can't
 
                debug_assert!(false, "I am actually called, my ID is {}", expr_id.index);
 
                let old_type = preexisting.get_mut();
 
                if let SingleInferenceResult::Incompatible = InferenceType::infer_subtree_for_single_type(
 
                    old_type, 0, &inference_type.parts, 0
 
                ) {
 
                    return Err(self.construct_expr_type_error(ctx, expr_id, expr_id))
 
                }
 
            }
 
        }
 

	
 
        Ok(())
 
    }
 

	
 
    fn insert_initial_call_polymorph_data(
 
        &mut self, ctx: &mut Ctx, call_id: CallExpressionId
 
    ) {
 
        use InferenceTypePart as ITP;
 

	
 
        // Note: the polymorph variables may be partially specified and may
 
        // contain references to the wrapping definition's (i.e. the proctype
 
        // we are currently visiting) polymorphic arguments.
 
        //
 
        // The arguments of the call may refer to polymorphic variables in the
 
        // definition of the function we're calling, not of the wrapping
 
        // definition. We insert markers in these inferred types to be able to
 
        // map them back and forth to the polymorphic arguments of the function
 
        // we are calling.
 
        let call = &ctx.heap[call_id];
 

	
 
        // Handle the polymorphic variables themselves
 
        let mut poly_vars = Vec::with_capacity(call.poly_args.len());
 
        for poly_arg_type_id in call.poly_args.clone() { // TODO: @performance
 
            poly_vars.push(self.determine_inference_type_from_parser_type(ctx, poly_arg_type_id, true));
 
        }
 

	
 
        // Handle the arguments
 
        // TODO: @cleanup: Maybe factor this out for reuse in the validator/linker, should also
 
        //  make the code slightly more robust.
 
        let (embedded_types, return_type) = match &call.method {
 
            Method::Create => {
 
                // Not polymorphic
 
                (
 
                    vec![InferenceType::new(false, true, vec![ITP::Int])],
 
                    InferenceType::new(false, true, vec![ITP::Message, ITP::Byte])
 
                )
 
            },
 
            Method::Fires => {
 
                // bool fires<T>(PortLike<T> arg)
 
                (
 
                    vec![InferenceType::new(true, false, vec![ITP::PortLike, ITP::MarkerBody(0), ITP::Unknown])],
 
                    InferenceType::new(false, true, vec![ITP::Bool])
 
                )
 
            },
 
            Method::Get => {
 
                // T get<T>(input<T> arg)
 
                (
 
                    vec![InferenceType::new(true, false, vec![ITP::Input, ITP::MarkerBody(0), ITP::Unknown])],
 
                    InferenceType::new(true, false, vec![ITP::MarkerBody(0), ITP::Unknown])
 
                )
 
            },
 
            Method::Put => {
 
                // void Put<T>(output<T> port, T msg)
 
                (
 
                    vec![
 
                        InferenceType::new(true, false, vec![ITP::Output, ITP::MarkerBody(0), ITP::Unknown]),
 
                        InferenceType::new(true, false, vec![ITP::MarkerBody(0), ITP::Unknown])
 
                    ],
 
                    InferenceType::new(false, true, vec![ITP::Void])
 
                )
 
            }
 
            Method::Symbolic(symbolic) => {
 
                let definition = &ctx.heap[symbolic.definition.unwrap()];
 

	
 
                match definition {
 
                    Definition::Component(definition) => {
 
                        let mut parameter_types = Vec::with_capacity(definition.parameters.len());
 
                        for param_id in definition.parameters.clone() {
 
                            let param = &ctx.heap[param_id];
 
                            let param_parser_type_id = param.parser_type;
 
                            parameter_types.push(self.determine_inference_type_from_parser_type(ctx, param_parser_type_id, false));
 
                        }
 

	
 
                        (parameter_types, InferenceType::new(false, true, vec![InferenceTypePart::Void]))
 
                    },
 
                    Definition::Function(definition) => {
 
                        let mut parameter_types = Vec::with_capacity(definition.parameters.len());
 
                        for param_id in definition.parameters.clone() {
 
                            let param = &ctx.heap[param_id];
 
                            let param_parser_type_id = param.parser_type;
 
                            parameter_types.push(self.determine_inference_type_from_parser_type(ctx, param_parser_type_id, false));
 
                        }
 

	
 
                        let return_type = self.determine_inference_type_from_parser_type(ctx, definition.return_type, false);
 
                        (parameter_types, return_type)
 
                    },
 
                    Definition::Struct(_) | Definition::Enum(_) => {
 
                        unreachable!("insert initial polymorph data for struct/enum");
 
                    }
 
                }
 
            }
 
        };
 

	
 
        self.extra_data.insert(call_id.upcast(), ExtraData {
 
            poly_vars,
 
            embedded: embedded_types,
 
            returned: return_type
 
        });
 
    }
 

	
 
    /// Determines the initial InferenceType from the provided ParserType. This
 
    /// may be called with two kinds of intentions:
 
    /// 1. To resolve a ParserType within the body of a function, or on
 
    ///     polymorphic arguments to calls/instantiations within that body. This
 
    ///     means that the polymorphic variables are known and can be replaced
 
    ///     with the monomorph we're instantiating.
 
    /// 2. To resolve a ParserType on a called function's definition or on
 
    ///     an instantiated datatype's members. This means that the polymorphic
 
    ///     arguments inside those ParserTypes refer to the polymorphic
 
    ///     variables in the called/instantiated type's definition.
 
    /// In the second case we place InferenceTypePart::Marker instances such
 
    /// that we can perform type inference on the polymorphic variables.
 
    fn determine_inference_type_from_parser_type(
 
        &mut self, ctx: &Ctx, parser_type_id: ParserTypeId,
 
        parser_type_in_body: bool
 
    ) -> InferenceType {
 
        use ParserTypeVariant as PTV;
 
        use InferenceTypePart as ITP;
 

	
 
        let mut to_consider = VecDeque::with_capacity(16);
 
        to_consider.push_back(parser_type_id);
 

	
 
        let mut infer_type = Vec::new();
 
        let mut has_inferred = false;
 
        let mut has_markers = false;
 

	
 
        while !to_consider.is_empty() {
 
            let parser_type_id = to_consider.pop_front().unwrap();
 
            let parser_type = &ctx.heap[parser_type_id];
 
            match &parser_type.variant {
 
                PTV::Message => {
 
                    /// TODO: @types Remove the Message -> Byte hack at some point...
 
                    // TODO: @types Remove the Message -> Byte hack at some point...
 
                    infer_type.push(ITP::Message);
 
                    infer_type.push(ITP::Byte);
 
                },
 
                PTV::Bool => { infer_type.push(ITP::Bool); },
 
                PTV::Byte => { infer_type.push(ITP::Byte); },
 
                PTV::Short => { infer_type.push(ITP::Short); },
 
                PTV::Int => { infer_type.push(ITP::Int); },
 
                PTV::Long => { infer_type.push(ITP::Long); },
 
                PTV::String => { infer_type.push(ITP::String); },
 
                PTV::IntegerLiteral => { unreachable!("integer literal type on variable type"); },
 
                PTV::Inferred => {
 
                    infer_type.push(ITP::Unknown);
 
                    has_inferred = true;
 
                },
 
                PTV::Array(subtype_id) => {
 
                    infer_type.push(ITP::Array);
 
                    to_consider.push_front(*subtype_id);
 
                },
 
                PTV::Input(subtype_id) => {
 
                    infer_type.push(ITP::Input);
 
                    to_consider.push_front(*subtype_id);
 
                },
 
                PTV::Output(subtype_id) => {
 
                    infer_type.push(ITP::Output);
 
                    to_consider.push_front(*subtype_id);
 
                },
 
                PTV::Symbolic(symbolic) => {
 
                    debug_assert!(symbolic.variant.is_some(), "symbolic variant not yet determined");
 
                    match symbolic.variant.as_ref().unwrap() {
 
                        SymbolicParserTypeVariant::PolyArg(_, arg_idx) => {
 
                            let arg_idx = *arg_idx;
 
                            debug_assert!(symbolic.poly_args.is_empty()); // TODO: @hkt
 

	
 
                            if parser_type_in_body {
 
                                // Polymorphic argument refers to definition's
 
                                // polymorphic variables
 
                                debug_assert!(arg_idx < self.poly_vars.len());
 
                                debug_assert!(!self.poly_vars[arg_idx].has_marker());
 
                                infer_type.push(ITP::MarkerDefinition(arg_idx));
 
                                for concrete_part in &self.poly_vars[arg_idx].parts {
 
                                    infer_type.push(ITP::from(*concrete_part));
 
                                }
 
                            } else {
 
                                // Polymorphic argument has to be inferred
 
                                has_markers = true;
 
                                has_inferred = true;
 
                                infer_type.push(ITP::MarkerBody(arg_idx));
 
                                infer_type.push(ITP::Unknown);
 
                            }
 
                        },
 
                        SymbolicParserTypeVariant::Definition(definition_id) => {
 
                            // TODO: @cleanup
 
                            if cfg!(debug_assertions) {
 
                                let definition = &ctx.heap[*definition_id];
 
                                debug_assert!(definition.is_struct() || definition.is_enum()); // TODO: @function_ptrs
 
                                let num_poly = match definition {
 
                                    Definition::Struct(v) => v.poly_vars.len(),
 
                                    Definition::Enum(v) => v.poly_vars.len(),
 
                                    _ => unreachable!(),
 
                                };
 
                                debug_assert_eq!(symbolic.poly_args.len(), num_poly);
 
                            }
 

	
 
                            infer_type.push(ITP::Instance(*definition_id, symbolic.poly_args.len()));
 
                            let mut poly_arg_idx = symbolic.poly_args.len();
 
                            while poly_arg_idx > 0 {
 
                                poly_arg_idx -= 1;
 
                                to_consider.push_front(symbolic.poly_args[poly_arg_idx]);
 
                            }
 
                        }
 
                    }
 
                }
 
            }
 
        }
 

	
 
        InferenceType::new(has_markers, !has_inferred, infer_type)
 
    }
 

	
 
    /// Construct an error when an expression's type does not match. This
 
    /// happens if we infer the expression type from its arguments (e.g. the
 
    /// expression type of an addition operator is the type of the arguments)
 
    /// But the expression type was already set due to our parent (e.g. an
 
    /// "if statement" or a "logical not" always expecting a boolean)
 
    fn construct_expr_type_error(
 
        &self, ctx: &Ctx, expr_id: ExpressionId, arg_id: ExpressionId
 
    ) -> ParseError2 {
 
        // TODO: Expand and provide more meaningful information for humans
 
        let expr = &ctx.heap[expr_id];
 
        let arg_expr = &ctx.heap[arg_id];
 
        let expr_type = self.expr_types.get(&expr_id).unwrap();
 
        let arg_type = self.expr_types.get(&arg_id).unwrap();
 

	
 
        return ParseError2::new_error(
 
            &ctx.module.source, expr.position(),
 
            &format!(
 
                "Incompatible types: this expression expected a '{}'", 
 
                expr_type.display_name(&ctx.heap)
 
            )
 
        ).with_postfixed_info(
 
            &ctx.module.source, arg_expr.position(),
 
            &format!(
 
                "But this expression yields a '{}'",
 
                arg_type.display_name(&ctx.heap)
 
            )
 
        )
 
    }
 

	
 
    fn construct_arg_type_error(
 
        &self, ctx: &Ctx, expr_id: ExpressionId,
 
        arg1_id: ExpressionId, arg2_id: ExpressionId
 
    ) -> ParseError2 {
 
        let expr = &ctx.heap[expr_id];
 
        let arg1 = &ctx.heap[arg1_id];
 
        let arg2 = &ctx.heap[arg2_id];
 

	
 
        let arg1_type = self.expr_types.get(&arg1_id).unwrap();
 
        let arg2_type = self.expr_types.get(&arg2_id).unwrap();
 

	
 
        return ParseError2::new_error(
 
            &ctx.module.source, expr.position(),
 
            "Incompatible types: cannot apply this expression"
 
        ).with_postfixed_info(
 
            &ctx.module.source, arg1.position(),
 
            &format!(
 
                "Because this expression has type '{}'",
 
                arg1_type.display_name(&ctx.heap)
 
            )
 
        ).with_postfixed_info(
 
            &ctx.module.source, arg2.position(),
 
            &format!(
 
                "But this expression has type '{}'",
 
                arg2_type.display_name(&ctx.heap)
 
            )
 
        )
 
    }
 

	
 
    fn construct_template_type_error(
 
        &self, ctx: &Ctx, expr_id: ExpressionId, template: &[InferenceTypePart]
 
    ) -> ParseError2 {
 
        let expr = &ctx.heap[expr_id];
 
        let expr_type = self.expr_types.get(&expr_id).unwrap();
 

	
 
        return ParseError2::new_error(
 
            &ctx.module.source, expr.position(),
 
            &format!(
 
                "Incompatible types: got a '{}' but expected a '{}'",
 
                expr_type.display_name(&ctx.heap), 
 
                InferenceType::partial_display_name(&ctx.heap, template)
 
            )
 
        )
 
    }
 

	
 
    /// Constructs a human interpretable error in the case that type inference
 
    /// on a polymorphic variable to a function call failed. This may only be
 
    /// caused by a pair of inference types (which may come from arguments or
 
    /// the return type) having two different inferred values for that
 
    /// polymorphic variable.
 
    ///
 
    /// So we find this pair (which may be a argument type or return type
 
    /// conflicting with itself) and construct the error using it.
 
    fn construct_poly_arg_error(
 
        &self, ctx: &Ctx, call_id: CallExpressionId
 
    ) -> ParseError2 {
 
        // Helper function to check for polymorph mismatch between two inference
 
        // types.
 
        fn has_poly_mismatch<'a>(type_a: &'a InferenceType, type_b: &'a InferenceType) -> Option<(usize, &'a [InferenceTypePart], &'a [InferenceTypePart])> {
 
            if !type_a.has_body_marker || !type_b.has_body_marker {
 
                return None
 
            }
 

	
 
            for (marker_a, section_a) in type_a.body_marker_iter() {
 
                for (marker_b, section_b) in type_b.body_marker_iter() {
 
                    if marker_a != marker_b {
 
                        // Not the same polymorphic variable
 
                        continue;
 
                    }
 

	
 
                    if !InferenceType::check_subtrees(section_a, 0, section_b, 0) {
 
                        // Not compatible
 
                        return Some((marker_a, section_a, section_b))
 
                    }
 
                }
 
            }
 

	
 
            None
 
        }
 

	
 
        // Helpers function to retrieve polyvar name and function name
 
        fn get_poly_var_and_func_name(ctx: &Ctx, poly_var_idx: usize, expr: &CallExpression) -> (String, String) {
 
            match &expr.method {
 
                Method::Create => unreachable!(),
 
                Method::Fires => (String::from('T'), String::from("fires")),
 
                Method::Get => (String::from('T'), String::from("get")),
 
                Method::Put => (String::from('T'), String::from("put")),
 
                Method::Symbolic(symbolic) => {
 
                    let definition = &ctx.heap[symbolic.definition.unwrap()];
 
                    let poly_var = match definition {
 
                        Definition::Struct(_) | Definition::Enum(_) => unreachable!(),
 
                        Definition::Function(definition) => {
 
                            String::from_utf8_lossy(&definition.poly_vars[poly_var_idx].value).to_string()
 
                        },
 
                        Definition::Component(definition) => {
 
                            String::from_utf8_lossy(&definition.poly_vars[poly_var_idx].value).to_string()
 
                        }
 
                    };
 
                    let func_name = String::from_utf8_lossy(&symbolic.identifier.value).to_string();
 
                    (poly_var, func_name)
 
                }
 
            }
 
        }
 

	
 
        // Helper function to construct initial error
 
        fn construct_main_error(ctx: &Ctx, poly_var_idx: usize, expr: &CallExpression) -> ParseError2 {
 
            let (poly_var, func_name) = get_poly_var_and_func_name(ctx, poly_var_idx, expr);
 
            return ParseError2::new_error(
 
                &ctx.module.source, expr.position(),
 
                &format!(
 
                    "Conflicting type for polymorphic variable '{}' of '{}'",
 
                    poly_var, func_name
 
                )
 
            )
 
        }
 

	
 
        // Actual checking
 
        let extra = self.extra_data.get(&call_id.upcast()).unwrap();
 
        let expr = &ctx.heap[call_id];
 

	
 
        // - check return type with itself
 
        if let Some((poly_idx, section_a, section_b)) = has_poly_mismatch(&extra.returned, &extra.returned) {
 
            return construct_main_error(ctx, poly_idx, expr)
 
                .with_postfixed_info(
 
                    &ctx.module.source, expr.position(),
 
                    &format!(
 
                        "The return type inferred the conflicting types '{}' and '{}'",
 
                        InferenceType::partial_display_name(&ctx.heap, section_a),
 
                        InferenceType::partial_display_name(&ctx.heap, section_b)
 
                    )
 
                )
 
        }
 

	
 
        // - check arguments with each other argument and with return type
 
        for (arg_a_idx, arg_a) in extra.embedded.iter().enumerate() {
 
            for (arg_b_idx, arg_b) in extra.embedded.iter().enumerate() {
 
                if arg_b_idx > arg_a_idx {
 
                    break;
 
                }
 

	
 
                if let Some((poly_idx, section_a, section_b)) = has_poly_mismatch(&arg_a, &arg_b) {
 
                    let error = construct_main_error(ctx, poly_idx, expr);
 
                    if arg_a_idx == arg_b_idx {
 
                        // Same argument
 
                        let arg = &ctx.heap[expr.arguments[arg_a_idx]];
 
                        return error.with_postfixed_info(
 
                            &ctx.module.source, arg.position(),
 
                            &format!(
 
                                "This argument inferred the conflicting types '{}' and '{}'",
 
                                InferenceType::partial_display_name(&ctx.heap, section_a),
 
                                InferenceType::partial_display_name(&ctx.heap, section_b)
 
                            )
 
                        )
 
                    } else {
 
                        let arg_a = &ctx.heap[expr.arguments[arg_a_idx]];
 
                        let arg_b = &ctx.heap[expr.arguments[arg_b_idx]];
 
                        return error.with_postfixed_info(
 
                            &ctx.module.source, arg_a.position(),
 
                            &format!(
 
                                "This argument inferred it to '{}'",
 
                                InferenceType::partial_display_name(&ctx.heap, section_a)
 
                            )
 
                        ).with_postfixed_info(
 
                            &ctx.module.source, arg_b.position(),
 
                            &format!(
 
                                "While this argument inferred it to '{}'",
 
                                InferenceType::partial_display_name(&ctx.heap, section_b)
 
                            )
 
                        )
 
                    }
 
                }
 
            }
 

	
 
            // Check with return type
 
            if let Some((poly_idx, section_arg, section_ret)) = has_poly_mismatch(arg_a, &extra.returned) {
 
                let arg = &ctx.heap[expr.arguments[arg_a_idx]];
 
                return construct_main_error(ctx, poly_idx, expr)
 
                    .with_postfixed_info(
 
                        &ctx.module.source, arg.position(),
 
                        &format!(
 
                            "This argument inferred it to '{}'",
 
                            InferenceType::partial_display_name(&ctx.heap, section_arg)
 
                        )
 
                    )
 
                    .with_postfixed_info(
 
                        &ctx.module.source, expr.position,
 
                        &format!(
 
                            "While the return type inferred it to '{}'",
 
                            InferenceType::partial_display_name(&ctx.heap, section_ret)
 
                        )
 
                    )
 
            }
 
        }
 

	
 
        unreachable!("construct_poly_arg_error without actual error found?")
 
    }
 
}
 

	
 
#[cfg(test)]
 
mod tests {
 
    use super::*;
 
    use crate::protocol::arena::Id;
 
    use InferenceTypePart as ITP;
 
    use InferenceType as IT;
 

	
 
    #[test]
 
    fn test_single_part_inference() {
 
        // lhs argument inferred from rhs
 
        let pairs = [
 
            (ITP::NumberLike, ITP::Byte),
 
            (ITP::IntegerLike, ITP::Int),
 
            (ITP::Unknown, ITP::Long),
 
            (ITP::Unknown, ITP::String)
 
        ];
 
        for (lhs, rhs) in pairs.iter() {
 
            // Using infer-both
 
            let mut lhs_type = IT::new(false, false, vec![lhs.clone()]);
 
            let mut rhs_type = IT::new(false, true, vec![rhs.clone()]);
 
            let result = unsafe{ IT::infer_subtrees_for_both_types(
 
                &mut lhs_type, 0, &mut rhs_type, 0
 
            ) };
 
            assert_eq!(DualInferenceResult::First, result);
 
            assert_eq!(lhs_type.parts, rhs_type.parts);
 

	
 
            // Using infer-single
 
            let mut lhs_type = IT::new(false, false, vec![lhs.clone()]);
 
            let rhs_type = IT::new(false, true, vec![rhs.clone()]);
 
            let result = IT::infer_subtree_for_single_type(
 
                &mut lhs_type, 0, &rhs_type.parts, 0
 
            );
 
            assert_eq!(SingleInferenceResult::Modified, result);
 
            assert_eq!(lhs_type.parts, rhs_type.parts);
 
        }
 
    }
 

	
 
    #[test]
 
    fn test_multi_part_inference() {
 
        let pairs = [
 
            (vec![ITP::ArrayLike, ITP::NumberLike], vec![ITP::Slice, ITP::Byte]),
 
            (vec![ITP::Unknown], vec![ITP::Input, ITP::Array, ITP::String]),
 
            (vec![ITP::PortLike, ITP::Int], vec![ITP::Input, ITP::Int]),
 
            (vec![ITP::Unknown], vec![ITP::Output, ITP::Int]),
 
            (
 
                vec![ITP::Instance(Id::new(0), 2), ITP::Input, ITP::Unknown, ITP::Output, ITP::Unknown],
 
                vec![ITP::Instance(Id::new(0), 2), ITP::Input, ITP::Array, ITP::Int, ITP::Output, ITP::Int]
 
            )
 
        ];
 

	
 
        for (lhs, rhs) in pairs.iter() {
 
            let mut lhs_type = IT::new(false, false, lhs.clone());
 
            let mut rhs_type = IT::new(false, false, rhs.clone());
 
            let result = unsafe{ IT::infer_subtrees_for_both_types(
 
                &mut lhs_type, 0, &mut rhs_type, 0
 
            ) };
 
            assert_eq!(DualInferenceResult::First, result);
 
            assert_eq!(lhs_type.parts, rhs_type.parts);
 

	
 
            let mut lhs_type = IT::new(false, false, lhs.clone());
 
            let rhs_type = IT::new(false, false, rhs.clone());
 
            let result = IT::infer_subtree_for_single_type(
 
                &mut lhs_type, 0, &rhs_type.parts, 0
 
            );
 
            assert_eq!(SingleInferenceResult::Modified, result);
 
            assert_eq!(lhs_type.parts, rhs_type.parts)
 
        }
 
    }
 
}
 
\ No newline at end of file
src/protocol/parser/visitor.rs
Show inline comments
 
use crate::protocol::ast::*;
 
use crate::protocol::inputsource::*;
 
use crate::protocol::parser::{symbol_table::*, type_table::*, LexedModule};
 

	
 
type Unit = ();
 
pub(crate) type VisitorResult = Result<Unit, ParseError2>;
 

	
 
/// Globally configured vector capacity for statement buffers in visitor 
 
/// implementations
 
pub(crate) const STMT_BUFFER_INIT_CAPACITY: usize = 256;
 
/// Globally configured vector capacity for expression buffers in visitor
 
/// implementations
 
pub(crate) const EXPR_BUFFER_INIT_CAPACITY: usize = 256;
 
/// Globally configured vector capacity for parser type buffers in visitor
 
/// implementations
 
pub(crate) const TYPE_BUFFER_INIT_CAPACITY: usize = 128;
 

	
 
/// General context structure that is used while traversing the AST.
 
pub(crate) struct Ctx<'p> {
 
    pub heap: &'p mut Heap,
 
    pub module: &'p LexedModule,
 
    pub symbols: &'p mut SymbolTable,
 
    pub types: &'p mut TypeTable,
 
}
 

	
 
/// Visitor is a generic trait that will fully walk the AST. The default
 
/// implementation of the visitors is to not recurse. The exception is the
 
/// top-level `visit_definition`, `visit_stmt` and `visit_expr` methods, which
 
/// call the appropriate visitor function.
 
pub(crate) trait Visitor2 {
 
    // Entry point
 
    fn visit_module(&mut self, ctx: &mut Ctx) -> VisitorResult {
 
        let mut def_index = 0;
 
        loop {
 
            let definition_id = {
 
                let root = &ctx.heap[ctx.module.root_id];
 
                if def_index >= root.definitions.len() {
 
                    return Ok(())
 
                }
 

	
 
                root.definitions[def_index]
 
            };
 

	
 
            self.visit_definition(ctx, definition_id)?;
 
            def_index += 1;
 
        }
 
    }
 

	
 
    // Definitions
 
    // --- enum matching
 
    fn visit_definition(&mut self, ctx: &mut Ctx, id: DefinitionId) -> VisitorResult {
 
        match &ctx.heap[id] {
 
            Definition::Enum(def) => {
 
                let def = def.this;
 
                self.visit_enum_definition(ctx, def)
 
            },
 
            Definition::Struct(def) => {
 
                let def = def.this;
 
                self.visit_struct_definition(ctx, def)
 
            },
 
            Definition::Component(def) => {
 
                let def = def.this;
 
                self.visit_component_definition(ctx, def)
 
            },
 
            Definition::Function(def) => {
 
                let def = def.this;
 
                self.visit_function_definition(ctx, def)
 
            }
 
        }
 
    }
 

	
 
    // --- enum variant handling
 
    fn visit_enum_definition(&mut self, _ctx: &mut Ctx, _id: EnumId) -> VisitorResult { Ok(()) }
 
    fn visit_struct_definition(&mut self, _ctx: &mut Ctx, _id: StructId) -> VisitorResult { Ok(()) }
 
    fn visit_component_definition(&mut self, _ctx: &mut Ctx, _id: ComponentId) -> VisitorResult { Ok(()) }
 
    fn visit_function_definition(&mut self, _ctx: &mut Ctx, _id: FunctionId) -> VisitorResult { Ok(()) }
 

	
 
    // Statements
 
    // --- enum matching
 
    fn visit_stmt(&mut self, ctx: &mut Ctx, id: StatementId) -> VisitorResult {
 
        match &ctx.heap[id] {
 
            Statement::Block(stmt) => {
 
                let this = stmt.this;
 
                self.visit_block_stmt(ctx, this)
 
            },
 
            Statement::Local(stmt) => {
 
                let this = stmt.this();
 
                self.visit_local_stmt(ctx, this)
 
            },
 
            Statement::Skip(stmt) => {
 
                let this = stmt.this;
 
                self.visit_skip_stmt(ctx, this)
 
            },
 
            Statement::Labeled(stmt) => {
 
                let this = stmt.this;
 
                self.visit_labeled_stmt(ctx, this)
 
            },
 
            Statement::If(stmt) => {
 
                let this = stmt.this;
 
                self.visit_if_stmt(ctx, this)
 
            },
 
            Statement::EndIf(_stmt) => Ok(()),
 
            Statement::While(stmt) => {
 
                let this = stmt.this;
 
                self.visit_while_stmt(ctx, this)
 
            },
 
            Statement::EndWhile(_stmt) => Ok(()),
 
            Statement::Break(stmt) => {
 
                let this = stmt.this;
 
                self.visit_break_stmt(ctx, this)
 
            },
 
            Statement::Continue(stmt) => {
 
                let this = stmt.this;
 
                self.visit_continue_stmt(ctx, this)
 
            },
 
            Statement::Synchronous(stmt) => {
 
                let this = stmt.this;
 
                self.visit_synchronous_stmt(ctx, this)
 
            },
 
            Statement::EndSynchronous(_stmt) => Ok(()),
 
            Statement::Return(stmt) => {
 
                let this = stmt.this;
 
                self.visit_return_stmt(ctx, this)
 
            },
 
            Statement::Assert(stmt) => {
 
                let this = stmt.this;
 
                self.visit_assert_stmt(ctx, this)
 
            },
 
            Statement::Goto(stmt) => {
 
                let this = stmt.this;
 
                self.visit_goto_stmt(ctx, this)
 
            },
 
            Statement::New(stmt) => {
 
                let this = stmt.this;
 
                self.visit_new_stmt(ctx, this)
 
            },
 
            Statement::Expression(stmt) => {
 
                let this = stmt.this;
 
                self.visit_expr_stmt(ctx, this)
 
            }
 
        }
 
    }
 

	
 
    fn visit_local_stmt(&mut self, ctx: &mut Ctx, id: LocalStatementId) -> VisitorResult {
 
        match &ctx.heap[id] {
 
            LocalStatement::Channel(stmt) => {
 
                let this = stmt.this;
 
                self.visit_local_channel_stmt(ctx, this)
 
            },
 
            LocalStatement::Memory(stmt) => {
 
                let this = stmt.this;
 
                self.visit_local_memory_stmt(ctx, this)
 
            },
 
        }
 
    }
 

	
 
    // --- enum variant handling
 
    fn visit_block_stmt(&mut self, _ctx: &mut Ctx, _id: BlockStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_local_memory_stmt(&mut self, _ctx: &mut Ctx, _id: MemoryStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_local_channel_stmt(&mut self, _ctx: &mut Ctx, _id: ChannelStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_skip_stmt(&mut self, _ctx: &mut Ctx, _id: SkipStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_labeled_stmt(&mut self, _ctx: &mut Ctx, _id: LabeledStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_if_stmt(&mut self, _ctx: &mut Ctx, _id: IfStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_while_stmt(&mut self, _ctx: &mut Ctx, _id: WhileStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_break_stmt(&mut self, _ctx: &mut Ctx, _id: BreakStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_continue_stmt(&mut self, _ctx: &mut Ctx, _id: ContinueStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_synchronous_stmt(&mut self, _ctx: &mut Ctx, _id: SynchronousStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_return_stmt(&mut self, _ctx: &mut Ctx, _id: ReturnStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_assert_stmt(&mut self, _ctx: &mut Ctx, _id: AssertStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_goto_stmt(&mut self, _ctx: &mut Ctx, _id: GotoStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_new_stmt(&mut self, _ctx: &mut Ctx, _id: NewStatementId) -> VisitorResult { Ok(()) }
 
    fn visit_expr_stmt(&mut self, _ctx: &mut Ctx, _id: ExpressionStatementId) -> VisitorResult { Ok(()) }
 

	
 
    // Expressions
 
    // --- enum matching
 
    fn visit_expr(&mut self, ctx: &mut Ctx, id: ExpressionId) -> VisitorResult {
 
        match &ctx.heap[id] {
 
            Expression::Assignment(expr) => {
 
                let this = expr.this;
 
                self.visit_assignment_expr(ctx, this)
 
            },
 
            Expression::Conditional(expr) => {
 
                let this = expr.this;
 
                self.visit_conditional_expr(ctx, this)
 
            }
 
            Expression::Binary(expr) => {
 
                let this = expr.this;
 
                self.visit_binary_expr(ctx, this)
 
            }
 
            Expression::Unary(expr) => {
 
                let this = expr.this;
 
                self.visit_unary_expr(ctx, this)
 
            }
 
            Expression::Indexing(expr) => {
 
                let this = expr.this;
 
                self.visit_indexing_expr(ctx, this)
 
            }
 
            Expression::Slicing(expr) => {
 
                let this = expr.this;
 
                self.visit_slicing_expr(ctx, this)
 
            }
 
            Expression::Select(expr) => {
 
                let this = expr.this;
 
                self.visit_select_expr(ctx, this)
 
            }
 
            Expression::Array(expr) => {
 
                let this = expr.this;
 
                self.visit_array_expr(ctx, this)
 
            }
 
            Expression::Constant(expr) => {
 
            Expression::Literal(expr) => {
 
                let this = expr.this;
 
                self.visit_constant_expr(ctx, this)
 
                self.visit_literal_expr(ctx, this)
 
            }
 
            Expression::Call(expr) => {
 
                let this = expr.this;
 
                self.visit_call_expr(ctx, this)
 
            }
 
            Expression::Variable(expr) => {
 
                let this = expr.this;
 
                self.visit_variable_expr(ctx, this)
 
            }
 
        }
 
    }
 

	
 
    fn visit_assignment_expr(&mut self, _ctx: &mut Ctx, _id: AssignmentExpressionId) -> VisitorResult { Ok(()) }
 
    fn visit_conditional_expr(&mut self, _ctx: &mut Ctx, _id: ConditionalExpressionId) -> VisitorResult { Ok(()) }
 
    fn visit_binary_expr(&mut self, _ctx: &mut Ctx, _id: BinaryExpressionId) -> VisitorResult { Ok(()) }
 
    fn visit_unary_expr(&mut self, _ctx: &mut Ctx, _id: UnaryExpressionId) -> VisitorResult { Ok(()) }
 
    fn visit_indexing_expr(&mut self, _ctx: &mut Ctx, _id: IndexingExpressionId) -> VisitorResult { Ok(()) }
 
    fn visit_slicing_expr(&mut self, _ctx: &mut Ctx, _id: SlicingExpressionId) -> VisitorResult { Ok(()) }
 
    fn visit_select_expr(&mut self, _ctx: &mut Ctx, _id: SelectExpressionId) -> VisitorResult { Ok(()) }
 
    fn visit_array_expr(&mut self, _ctx: &mut Ctx, _id: ArrayExpressionId) -> VisitorResult { Ok(()) }
 
    fn visit_constant_expr(&mut self, _ctx: &mut Ctx, _id: ConstantExpressionId) -> VisitorResult { Ok(()) }
 
    fn visit_literal_expr(&mut self, _ctx: &mut Ctx, _id: LiteralExpressionId) -> VisitorResult { Ok(()) }
 
    fn visit_call_expr(&mut self, _ctx: &mut Ctx, _id: CallExpressionId) -> VisitorResult { Ok(()) }
 
    fn visit_variable_expr(&mut self, _ctx: &mut Ctx, _id: VariableExpressionId) -> VisitorResult { Ok(()) }
 

	
 
    // Types
 
    fn visit_parser_type(&mut self, _ctx: &mut Ctx, _id: ParserTypeId) -> VisitorResult { Ok(()) }
 
}
 
\ No newline at end of file
src/protocol/parser/visitor_linker.rs
Show inline comments
 
@@ -314,773 +314,793 @@ impl Visitor2 for ValidityAndLinkerVisitor {
 
            let (test_id, body_id) = {
 
                let stmt = &ctx.heap[id];
 
                (stmt.test, stmt.body)
 
            };
 
            let old_while = self.in_while.replace(id);
 
            debug_assert_eq!(self.expr_parent, ExpressionParent::None);
 
            self.expr_parent = ExpressionParent::While(id);
 
            self.visit_expr(ctx, test_id)?;
 
            self.expr_parent = ExpressionParent::None;
 

	
 
            self.visit_stmt(ctx, body_id)?;
 
            self.in_while = old_while;
 
        }
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_break_stmt(&mut self, ctx: &mut Ctx, id: BreakStatementId) -> VisitorResult {
 
        if self.performing_breadth_pass {
 
            // Should be able to resolve break statements with a label in the
 
            // breadth pass, no need to do after resolving all labels
 
            let target_end_while = {
 
                let stmt = &ctx.heap[id];
 
                let target_while_id = self.resolve_break_or_continue_target(ctx, stmt.position, &stmt.label)?;
 
                let target_while = &ctx.heap[target_while_id];
 
                debug_assert!(target_while.end_while.is_some());
 
                target_while.end_while.unwrap()
 
            };
 

	
 
            let stmt = &mut ctx.heap[id];
 
            stmt.target = Some(target_end_while);
 
        }
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_continue_stmt(&mut self, ctx: &mut Ctx, id: ContinueStatementId) -> VisitorResult {
 
        if self.performing_breadth_pass {
 
            let target_while_id = {
 
                let stmt = &ctx.heap[id];
 
                self.resolve_break_or_continue_target(ctx, stmt.position, &stmt.label)?
 
            };
 

	
 
            let stmt = &mut ctx.heap[id];
 
            stmt.target = Some(target_while_id)
 
        }
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_synchronous_stmt(&mut self, ctx: &mut Ctx, id: SynchronousStatementId) -> VisitorResult {
 
        if self.performing_breadth_pass {
 
            // Check for validity of synchronous statement
 
            let cur_sync_position = ctx.heap[id].position;
 
            if self.in_sync.is_some() {
 
                // Nested synchronous statement
 
                let old_sync = &ctx.heap[self.in_sync.unwrap()];
 
                return Err(
 
                    ParseError2::new_error(&ctx.module.source, cur_sync_position, "Illegal nested synchronous statement")
 
                        .with_postfixed_info(&ctx.module.source, old_sync.position, "It is nested in this synchronous statement")
 
                );
 
            }
 

	
 
            if !self.def_type.is_primitive() {
 
                return Err(ParseError2::new_error(
 
                    &ctx.module.source, cur_sync_position,
 
                    "Synchronous statements may only be used in primitive components"
 
                ));
 
            }
 

	
 
            // Append SynchronousEnd pseudo-statement
 
            let sync_end_id = ctx.heap.alloc_end_synchronous_statement(|this| EndSynchronousStatement{
 
                this,
 
                position: cur_sync_position,
 
                start_sync: id,
 
                next: None,
 
            });
 
            let sync_start = &mut ctx.heap[id];
 
            sync_start.end_sync = Some(sync_end_id);
 
            self.insert_buffer.push((self.relative_pos_in_block + 1, sync_end_id.upcast()));
 
        } else {
 
            let sync_body = ctx.heap[id].body;
 
            let old = self.in_sync.replace(id);
 
            self.visit_stmt_with_hint(ctx, sync_body, Some(id))?;
 
            self.in_sync = old;
 
        }
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_return_stmt(&mut self, ctx: &mut Ctx, id: ReturnStatementId) -> VisitorResult {
 
        if self.performing_breadth_pass {
 
            let stmt = &ctx.heap[id];
 
            if !self.def_type.is_function() {
 
                return Err(
 
                    ParseError2::new_error(&ctx.module.source, stmt.position, "Return statements may only appear in function bodies")
 
                );
 
            }
 
        } else {
 
            // If here then we are within a function
 
            debug_assert_eq!(self.expr_parent, ExpressionParent::None);
 
            self.expr_parent = ExpressionParent::Return(id);
 
            self.visit_expr(ctx, ctx.heap[id].expression)?;
 
            self.expr_parent = ExpressionParent::None;
 
        }
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_assert_stmt(&mut self, ctx: &mut Ctx, id: AssertStatementId) -> VisitorResult {
 
        let stmt = &ctx.heap[id];
 
        if self.performing_breadth_pass {
 
            if self.def_type.is_function() {
 
                // TODO: We probably want to allow this. Mark the function as
 
                //  using asserts, and then only allow calls to these functions
 
                //  within components. Such a marker will cascade through any
 
                //  functions that then call an asserting function
 
                return Err(
 
                    ParseError2::new_error(&ctx.module.source, stmt.position, "Illegal assert statement in a function")
 
                );
 
            }
 

	
 
            // We are in a component of some sort, but we also need to be within a
 
            // synchronous statement
 
            if self.in_sync.is_none() {
 
                return Err(
 
                    ParseError2::new_error(&ctx.module.source, stmt.position, "Illegal assert statement outside of a synchronous block")
 
                );
 
            }
 
        } else {
 
            debug_assert_eq!(self.expr_parent, ExpressionParent::None);
 
            let expr_id = stmt.expression;
 

	
 
            self.expr_parent = ExpressionParent::Assert(id);
 
            self.visit_expr(ctx, expr_id)?;
 
            self.expr_parent = ExpressionParent::None;
 
        }
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_goto_stmt(&mut self, ctx: &mut Ctx, id: GotoStatementId) -> VisitorResult {
 
        if !self.performing_breadth_pass {
 
            // Must perform goto label resolving after the breadth pass, this
 
            // way we are able to find all the labels in current and outer
 
            // scopes.
 
            let target_id = self.find_label(ctx, &ctx.heap[id].label)?;
 
            ctx.heap[id].target = Some(target_id);
 

	
 
            let target = &ctx.heap[target_id];
 
            if self.in_sync != target.in_sync {
 
                // We can only goto the current scope or outer scopes. Because
 
                // nested sync statements are not allowed so if the value does
 
                // not match, then we must be inside a sync scope
 
                debug_assert!(self.in_sync.is_some());
 
                let goto_stmt = &ctx.heap[id];
 
                let sync_stmt = &ctx.heap[self.in_sync.unwrap()];
 
                return Err(
 
                    ParseError2::new_error(&ctx.module.source, goto_stmt.position, "Goto may not escape the surrounding synchronous block")
 
                        .with_postfixed_info(&ctx.module.source, target.position, "This is the target of the goto statement")
 
                        .with_postfixed_info(&ctx.module.source, sync_stmt.position, "Which will jump past this statement")
 
                );
 
            }
 
        }
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_new_stmt(&mut self, ctx: &mut Ctx, id: NewStatementId) -> VisitorResult {
 
        // Link the call expression following the new statement
 
        if self.performing_breadth_pass {
 
            // TODO: Cleanup error messages, can be done cleaner
 
            // Make sure new statement occurs within a composite component
 
            let call_expr_id = ctx.heap[id].expression;
 
            if !self.def_type.is_composite() {
 
                let new_stmt = &ctx.heap[id];
 
                return Err(
 
                    ParseError2::new_error(&ctx.module.source, new_stmt.position, "Instantiating components may only be done in composite components")
 
                );
 
            }
 

	
 
            // We make sure that we point to a symbolic method. Checking that it
 
            // points to a component is done in the depth pass.
 
            let call_expr = &ctx.heap[call_expr_id];
 
            if let Method::Symbolic(_) = &call_expr.method {
 
                // We're fine
 
            } else {
 
                return Err(
 
                    ParseError2::new_error(&ctx.module.source, call_expr.position, "Must instantiate a component")
 
                );
 
            }
 
        } else {
 
            // Just call `visit_call_expr`. We do some extra work we don't have
 
            // to, but this prevents silly mistakes.
 
            let call_expr_id = ctx.heap[id].expression;
 

	
 
            debug_assert_eq!(self.expr_parent, ExpressionParent::None);
 
            self.expr_parent = ExpressionParent::New(id);
 
            self.visit_call_expr(ctx, call_expr_id)?;
 
            self.expr_parent = ExpressionParent::None;
 
        }
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_expr_stmt(&mut self, ctx: &mut Ctx, id: ExpressionStatementId) -> VisitorResult {
 
        if !self.performing_breadth_pass {
 
            let expr_id = ctx.heap[id].expression;
 

	
 
            debug_assert_eq!(self.expr_parent, ExpressionParent::None);
 
            self.expr_parent = ExpressionParent::ExpressionStmt(id);
 
            self.visit_expr(ctx, expr_id)?;
 
            self.expr_parent = ExpressionParent::None;
 
        }
 

	
 
        Ok(())
 
    }
 

	
 

	
 
    //--------------------------------------------------------------------------
 
    // Expression visitors
 
    //--------------------------------------------------------------------------
 

	
 
    fn visit_assignment_expr(&mut self, ctx: &mut Ctx, id: AssignmentExpressionId) -> VisitorResult {
 
        debug_assert!(!self.performing_breadth_pass);
 

	
 
        let upcast_id = id.upcast();
 
        let assignment_expr = &mut ctx.heap[id];
 

	
 
        let left_expr_id = assignment_expr.left;
 
        let right_expr_id = assignment_expr.right;
 
        let old_expr_parent = self.expr_parent;
 
        assignment_expr.parent = old_expr_parent;
 

	
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
 
        self.visit_expr(ctx, left_expr_id)?;
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
 
        self.visit_expr(ctx, right_expr_id)?;
 
        self.expr_parent = old_expr_parent;
 
        Ok(())
 
    }
 

	
 
    fn visit_conditional_expr(&mut self, ctx: &mut Ctx, id: ConditionalExpressionId) -> VisitorResult {
 
        debug_assert!(!self.performing_breadth_pass);
 
        let upcast_id = id.upcast();
 
        let conditional_expr = &mut ctx.heap[id];
 

	
 
        let test_expr_id = conditional_expr.test;
 
        let true_expr_id = conditional_expr.true_expression;
 
        let false_expr_id = conditional_expr.false_expression;
 

	
 
        let old_expr_parent = self.expr_parent;
 
        conditional_expr.parent = old_expr_parent;
 

	
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
 
        self.visit_expr(ctx, test_expr_id)?;
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
 
        self.visit_expr(ctx, true_expr_id)?;
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 2);
 
        self.visit_expr(ctx, false_expr_id)?;
 
        self.expr_parent = old_expr_parent;
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_binary_expr(&mut self, ctx: &mut Ctx, id: BinaryExpressionId) -> VisitorResult {
 
        debug_assert!(!self.performing_breadth_pass);
 
        let upcast_id = id.upcast();
 
        let binary_expr = &mut ctx.heap[id];
 
        let left_expr_id = binary_expr.left;
 
        let right_expr_id = binary_expr.right;
 

	
 
        let old_expr_parent = self.expr_parent;
 
        binary_expr.parent = old_expr_parent;
 

	
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
 
        self.visit_expr(ctx, left_expr_id)?;
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
 
        self.visit_expr(ctx, right_expr_id)?;
 
        self.expr_parent = old_expr_parent;
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_unary_expr(&mut self, ctx: &mut Ctx, id: UnaryExpressionId) -> VisitorResult {
 
        debug_assert!(!self.performing_breadth_pass);
 

	
 
        let unary_expr = &mut ctx.heap[id];
 
        let expr_id = unary_expr.expression;
 

	
 
        let old_expr_parent = self.expr_parent;
 
        unary_expr.parent = old_expr_parent;
 

	
 
        self.expr_parent = ExpressionParent::Expression(id.upcast(), 0);
 
        self.visit_expr(ctx, expr_id)?;
 
        self.expr_parent = old_expr_parent;
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_indexing_expr(&mut self, ctx: &mut Ctx, id: IndexingExpressionId) -> VisitorResult {
 
        debug_assert!(!self.performing_breadth_pass);
 
        let upcast_id = id.upcast();
 
        let indexing_expr = &mut ctx.heap[id];
 

	
 
        let subject_expr_id = indexing_expr.subject;
 
        let index_expr_id = indexing_expr.index;
 

	
 
        let old_expr_parent = self.expr_parent;
 
        indexing_expr.parent = old_expr_parent;
 

	
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
 
        self.visit_expr(ctx, subject_expr_id)?;
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
 
        self.visit_expr(ctx, index_expr_id)?;
 
        self.expr_parent = old_expr_parent;
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_slicing_expr(&mut self, ctx: &mut Ctx, id: SlicingExpressionId) -> VisitorResult {
 
        debug_assert!(!self.performing_breadth_pass);
 
        let upcast_id = id.upcast();
 
        let slicing_expr = &mut ctx.heap[id];
 

	
 
        let subject_expr_id = slicing_expr.subject;
 
        let from_expr_id = slicing_expr.from_index;
 
        let to_expr_id = slicing_expr.to_index;
 

	
 
        let old_expr_parent = self.expr_parent;
 
        slicing_expr.parent = old_expr_parent;
 

	
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
 
        self.visit_expr(ctx, subject_expr_id)?;
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
 
        self.visit_expr(ctx, from_expr_id)?;
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 2);
 
        self.visit_expr(ctx, to_expr_id)?;
 
        self.expr_parent = old_expr_parent;
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_select_expr(&mut self, ctx: &mut Ctx, id: SelectExpressionId) -> VisitorResult {
 
        debug_assert!(!self.performing_breadth_pass);
 

	
 
        let select_expr = &mut ctx.heap[id];
 
        let expr_id = select_expr.subject;
 

	
 
        let old_expr_parent = self.expr_parent;
 
        select_expr.parent = old_expr_parent;
 

	
 
        self.expr_parent = ExpressionParent::Expression(id.upcast(), 0);
 
        self.visit_expr(ctx, expr_id)?;
 
        self.expr_parent = old_expr_parent;
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_array_expr(&mut self, ctx: &mut Ctx, id: ArrayExpressionId) -> VisitorResult {
 
        debug_assert!(!self.performing_breadth_pass);
 

	
 
        let upcast_id = id.upcast();
 
        let array_expr = &mut ctx.heap[id];
 

	
 
        let old_num_exprs = self.expression_buffer.len();
 
        self.expression_buffer.extend(&array_expr.elements);
 
        let new_num_exprs = self.expression_buffer.len();
 

	
 
        let old_expr_parent = self.expr_parent;
 
        array_expr.parent = old_expr_parent;
 

	
 
        for field_expr_idx in old_num_exprs..new_num_exprs {
 
            let field_expr_id = self.expression_buffer[field_expr_idx];
 
            self.expr_parent = ExpressionParent::Expression(upcast_id, field_expr_idx as u32);
 
            self.visit_expr(ctx, field_expr_id)?;
 
        }
 

	
 
        self.expression_buffer.truncate(old_num_exprs);
 
        self.expr_parent = old_expr_parent;
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_constant_expr(&mut self, ctx: &mut Ctx, id: ConstantExpressionId) -> VisitorResult {
 
    fn visit_literal_expr(&mut self, ctx: &mut Ctx, id: LiteralExpressionId) -> VisitorResult {
 
        debug_assert!(!self.performing_breadth_pass);
 

	
 
        let constant_expr = &mut ctx.heap[id];
 
        constant_expr.parent = self.expr_parent;
 
        let old_expr_parent = self.expr_parent;
 
        constant_expr.parent = old_expr_parent;
 

	
 
        match &mut constant_expr.value {
 
            Literal::Null | Literal::True | Literal::False |
 
            Literal::Character(_) | Literal::Integer(_) => {
 
                // Just the parent has to be set, done above
 
            },
 
            Literal::Struct(literal) => {
 
                // Retrieve and set the literals definition
 
                let definition =
 
                // Need to traverse fields expressions in struct
 
                let old_num_exprs = self.expression_buffer.len();
 
                self.expression_buffer.extend(literal.fields.iter().map(|v| v.value));
 
                let new_num_exprs = self.expression_buffer.len();
 

	
 
                self.expression_buffer.truncate(old_num_exprs);
 
            }
 
        }
 

	
 
        self.expr_parent = old_expr_parent;
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_call_expr(&mut self, ctx: &mut Ctx, id: CallExpressionId) -> VisitorResult {
 
        debug_assert!(!self.performing_breadth_pass);
 

	
 
        let call_expr = &mut ctx.heap[id];
 
        let num_expr_args = call_expr.arguments.len();
 

	
 
        // Resolve the method to the appropriate definition and check the
 
        // legality of the particular method call.
 
        // TODO: @cleanup Unify in some kind of signature call, see similar
 
        //  cleanup comments with this `match` format.
 
        let num_definition_args;
 
        match &mut call_expr.method {
 
            Method::Create => {
 
                num_definition_args = 1;
 
            },
 
            Method::Fires => {
 
                if !self.def_type.is_primitive() {
 
                    return Err(ParseError2::new_error(
 
                        &ctx.module.source, call_expr.position,
 
                        "A call to 'fires' may only occur in primitive component definitions"
 
                    ));
 
                }
 
                if self.in_sync.is_none() {
 
                    return Err(ParseError2::new_error(
 
                        &ctx.module.source, call_expr.position,
 
                        "A call to 'fires' may only occur inside synchronous blocks"
 
                    ));
 
                }
 
                num_definition_args = 1;
 
            },
 
            Method::Get => {
 
                if !self.def_type.is_primitive() {
 
                    return Err(ParseError2::new_error(
 
                        &ctx.module.source, call_expr.position,
 
                        "A call to 'get' may only occur in primitive component definitions"
 
                    ));
 
                }
 
                if self.in_sync.is_none() {
 
                    return Err(ParseError2::new_error(
 
                        &ctx.module.source, call_expr.position,
 
                        "A call to 'get' may only occur inside synchronous blocks"
 
                    ));
 
                }
 
                num_definition_args = 1;
 
            },
 
            Method::Put => {
 
                if !self.def_type.is_primitive() {
 
                    return Err(ParseError2::new_error(
 
                        &ctx.module.source, call_expr.position,
 
                        "A call to 'put' may only occur in primitive component definitions"
 
                    ));
 
                }
 
                if self.in_sync.is_none() {
 
                    return Err(ParseError2::new_error(
 
                        &ctx.module.source, call_expr.position,
 
                        "A call to 'put' may only occur inside synchronous blocks"
 
                    ));
 
                }
 
                num_definition_args = 2;
 
            }
 
            Method::Symbolic(symbolic) => {
 
                // Find symbolic method
 
                let (verb, expected_type) = if let ExpressionParent::New(_) = self.expr_parent {
 
                    // Expect to find a component
 
                    ("instantiated", TypeClass::Component)
 
                } else {
 
                    // Expect to find a function
 
                    ("called", TypeClass::Function)
 
                };
 

	
 
                let found_symbol = self.find_symbol_of_type(
 
                    ctx.module.root_id, &ctx.symbols, &ctx.types,
 
                    &symbolic.identifier, expected_type
 
                );
 
                let definition_id = match found_symbol {
 
                    FindOfTypeResult::Found(definition_id) => definition_id,
 
                    FindOfTypeResult::TypeMismatch(got_type_class) => {
 
                        return Err(ParseError2::new_error(
 
                            &ctx.module.source, symbolic.identifier.position,
 
                            &format!(
 
                                "Only {}s can be {}, this identifier points to a {}",
 
                                expected_type, verb, got_type_class
 
                            )
 
                        ))
 
                    },
 
                    FindOfTypeResult::NotFound => {
 
                        return Err(ParseError2::new_error(
 
                            &ctx.module.source, symbolic.identifier.position,
 
                            &format!("Could not find a {} with this name", expected_type)
 
                        ))
 
                    }
 
                };
 

	
 
                symbolic.definition = Some(definition_id);
 
                match &ctx.types.get_base_definition(&definition_id).unwrap().definition {
 
                    DefinedTypeVariant::Function(definition) => {
 
                        num_definition_args = definition.arguments.len();
 
                    },
 
                    DefinedTypeVariant::Component(definition) => {
 
                        num_definition_args = definition.arguments.len();
 
                    }
 
                    _ => unreachable!(),
 
                }
 
            }
 
        }
 

	
 
        // Check the poly args and the number of variables in the call
 
        // expression
 
        self.visit_call_poly_args(ctx, id)?;
 
        let call_expr = &mut ctx.heap[id];
 
        if num_expr_args != num_definition_args {
 
            return Err(ParseError2::new_error(
 
                &ctx.module.source, call_expr.position,
 
                &format!(
 
                    "This call expects {} arguments, but {} were provided",
 
                    num_definition_args, num_expr_args
 
                )
 
            ));
 
        }
 

	
 
        // Recurse into all of the arguments and set the expression's parent
 
        let upcast_id = id.upcast();
 

	
 
        let old_num_exprs = self.expression_buffer.len();
 
        self.expression_buffer.extend(&call_expr.arguments);
 
        let new_num_exprs = self.expression_buffer.len();
 

	
 
        let old_expr_parent = self.expr_parent;
 
        call_expr.parent = old_expr_parent;
 

	
 
        for arg_expr_idx in old_num_exprs..new_num_exprs {
 
            let arg_expr_id = self.expression_buffer[arg_expr_idx];
 
            self.expr_parent = ExpressionParent::Expression(upcast_id, arg_expr_idx as u32);
 
            self.visit_expr(ctx, arg_expr_id)?;
 
        }
 

	
 
        self.expression_buffer.truncate(old_num_exprs);
 
        self.expr_parent = old_expr_parent;
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_variable_expr(&mut self, ctx: &mut Ctx, id: VariableExpressionId) -> VisitorResult {
 
        debug_assert!(!self.performing_breadth_pass);
 

	
 
        let var_expr = &ctx.heap[id];
 
        let variable_id = self.find_variable(ctx, self.relative_pos_in_block, &var_expr.identifier)?;
 
        let var_expr = &mut ctx.heap[id];
 
        var_expr.declaration = Some(variable_id);
 
        var_expr.parent = self.expr_parent;
 

	
 
        Ok(())
 
    }
 

	
 
    //--------------------------------------------------------------------------
 
    // ParserType visitors
 
    //--------------------------------------------------------------------------
 

	
 
    fn visit_parser_type(&mut self, ctx: &mut Ctx, id: ParserTypeId) -> VisitorResult {
 
        let old_num_types = self.parser_type_buffer.len();
 
        match self.visit_parser_type_without_buffer_cleanup(ctx, id) {
 
            Ok(_) => {
 
                debug_assert_eq!(self.parser_type_buffer.len(), old_num_types);
 
                Ok(())
 
            },
 
            Err(err) => {
 
                self.parser_type_buffer.truncate(old_num_types);
 
                Err(err)
 
            }
 
        }
 
    }
 
}
 

	
 
enum FindOfTypeResult {
 
    // Identifier was exactly matched, type matched as well
 
    Found(DefinitionId),
 
    // Identifier was matched, but the type differs from the expected one
 
    TypeMismatch(&'static str),
 
    // Identifier could not be found
 
    NotFound,
 
}
 

	
 
impl ValidityAndLinkerVisitor {
 
    //--------------------------------------------------------------------------
 
    // Special traversal
 
    //--------------------------------------------------------------------------
 

	
 
    /// Will visit a statement with a hint about its wrapping statement. This is
 
    /// used to distinguish block statements with a wrapping synchronous
 
    /// statement from normal block statements.
 
    fn visit_stmt_with_hint(&mut self, ctx: &mut Ctx, id: StatementId, hint: Option<SynchronousStatementId>) -> VisitorResult {
 
        if let Statement::Block(block_stmt) = &ctx.heap[id] {
 
            let block_id = block_stmt.this;
 
            self.visit_block_stmt_with_hint(ctx, block_id, hint)
 
        } else {
 
            self.visit_stmt(ctx, id)
 
        }
 
    }
 

	
 
    fn visit_block_stmt_with_hint(&mut self, ctx: &mut Ctx, id: BlockStatementId, hint: Option<SynchronousStatementId>) -> VisitorResult {
 
        if self.performing_breadth_pass {
 
            // Performing a breadth pass, so don't traverse into the statements
 
            // of the block.
 
            return Ok(())
 
        }
 

	
 
        // Set parent scope and relative position in the parent scope. Remember
 
        // these values to set them back to the old values when we're done with
 
        // the traversal of the block's statements.
 
        let body = &mut ctx.heap[id];
 
        body.parent_scope = self.cur_scope.clone();
 
        body.relative_pos_in_parent = self.relative_pos_in_block;
 

	
 
        let old_scope = self.cur_scope.replace(match hint {
 
            Some(sync_id) => Scope::Synchronous((sync_id, id)),
 
            None => Scope::Regular(id),
 
        });
 
        let old_relative_pos = self.relative_pos_in_block;
 

	
 
        // Copy statement IDs into buffer
 
        let old_num_stmts = self.statement_buffer.len();
 
        {
 
            let body = &ctx.heap[id];
 
            self.statement_buffer.extend_from_slice(&body.statements);
 
        }
 
        let new_num_stmts = self.statement_buffer.len();
 

	
 
        // Perform the breadth-first pass. Its main purpose is to find labeled
 
        // statements such that we can find the `goto`-targets immediately when
 
        // performing the depth pass
 
        self.performing_breadth_pass = true;
 
        for stmt_idx in old_num_stmts..new_num_stmts {
 
            self.relative_pos_in_block = (stmt_idx - old_num_stmts) as u32;
 
            self.visit_stmt(ctx, self.statement_buffer[stmt_idx])?;
 
        }
 

	
 
        if !self.insert_buffer.is_empty() {
 
            let body = &mut ctx.heap[id];
 
            for (insert_idx, (pos, stmt)) in self.insert_buffer.drain(..).enumerate() {
 
                body.statements.insert(pos as usize + insert_idx, stmt);
 
            }
 
        }
 

	
 
        // And the depth pass. Because we're not actually visiting any inserted
 
        // nodes because we're using the statement buffer, we may safely use the
 
        // relative_pos_in_block counter.
 
        self.performing_breadth_pass = false;
 
        for stmt_idx in old_num_stmts..new_num_stmts {
 
            self.relative_pos_in_block = (stmt_idx - old_num_stmts) as u32;
 
            self.visit_stmt(ctx, self.statement_buffer[stmt_idx])?;
 
        }
 

	
 
        self.cur_scope = old_scope;
 
        self.relative_pos_in_block = old_relative_pos;
 

	
 
        // Pop statement buffer
 
        debug_assert!(self.insert_buffer.is_empty(), "insert buffer not empty after depth pass");
 
        self.statement_buffer.truncate(old_num_stmts);
 

	
 
        Ok(())
 
    }
 

	
 
    /// Visits a particular ParserType in the AST and resolves temporary and
 
    /// implicitly inferred types into the appropriate tree. Note that a
 
    /// ParserType node is a tree. Only call this function on the root node of
 
    /// that tree to prevent doing work more than once.
 
    fn visit_parser_type_without_buffer_cleanup(&mut self, ctx: &mut Ctx, id: ParserTypeId) -> VisitorResult {
 
        use ParserTypeVariant as PTV;
 
        debug_assert!(!self.performing_breadth_pass);
 

	
 
        let init_num_types = self.parser_type_buffer.len();
 
        self.parser_type_buffer.push(id);
 

	
 
        'resolve_loop: while self.parser_type_buffer.len() > init_num_types {
 
            let parser_type_id = self.parser_type_buffer.pop().unwrap();
 
            let parser_type = &ctx.heap[parser_type_id];
 

	
 
            let (symbolic_pos, symbolic_variant, num_inferred_to_allocate) = match &parser_type.variant {
 
                PTV::Message | PTV::Bool |
 
                PTV::Byte | PTV::Short | PTV::Int | PTV::Long |
 
                PTV::String |
 
                PTV::IntegerLiteral | PTV::Inferred => {
 
                    // Builtin types or types that do not require recursion
 
                    continue 'resolve_loop;
 
                },
 
                PTV::Array(subtype_id) |
 
                PTV::Input(subtype_id) |
 
                PTV::Output(subtype_id) => {
 
                    // Requires recursing
 
                    self.parser_type_buffer.push(*subtype_id);
 
                    continue 'resolve_loop;
 
                },
 
                PTV::Symbolic(symbolic) => {
 
                    // Retrieve poly_vars from function/component definition to
 
                    // match against.
 
                    let (definition_id, poly_vars) = match self.def_type {
 
                        DefinitionType::None => unreachable!(),
 
                        DefinitionType::Primitive(id) => (id.upcast(), &ctx.heap[id].poly_vars),
 
                        DefinitionType::Composite(id) => (id.upcast(), &ctx.heap[id].poly_vars),
 
                        DefinitionType::Function(id) => (id.upcast(), &ctx.heap[id].poly_vars),
 
                    };
 

	
 
                    let mut symbolic_variant = None;
 
                    for (poly_var_idx, poly_var) in poly_vars.iter().enumerate() {
 
                        if symbolic.identifier.value == poly_var.value {
 
                            // Type refers to a polymorphic variable.
 
                            // TODO: @hkt Maybe allow higher-kinded types?
 
                            if !symbolic.poly_args.is_empty() {
 
                                return Err(ParseError2::new_error(
 
                                    &ctx.module.source, symbolic.identifier.position,
 
                                    "Polymorphic arguments to a polymorphic variable (higher-kinded types) are not allowed (yet)"
 
                                ));
 
                            }
 
                            symbolic_variant = Some(SymbolicParserTypeVariant::PolyArg(definition_id, poly_var_idx));
 
                        }
 
                    }
 

	
 
                    if let Some(symbolic_variant) = symbolic_variant {
 
                        // Identifier points to a symbolic type
 
                        (symbolic.identifier.position, symbolic_variant, 0)
 
                    } else {
 
                        // Must be a user-defined type, otherwise an error
 
                        let found_type = find_type_definition(
 
                            &ctx.symbols, &ctx.types, ctx.module.root_id, &symbolic.identifier
 
                        ).as_parse_error(&ctx.module.source)?;
 
                        symbolic_variant = Some(SymbolicParserTypeVariant::Definition(found_type.ast_definition));
 

	
 
                        // TODO: @function_ptrs: Allow function pointers at some
 
                        //  point in the future
 
                        if found_type.definition.type_class().is_proc_type() {
 
                            return Err(ParseError2::new_error(
 
                                &ctx.module.source, symbolic.identifier.position,
 
                                &format!(
 
                                    "This identifier points to a {} type, expected a datatype",
 
                                    found_type.definition.type_class()
 
                                )
 
                            ));
 
                        }
 

	
 
                        // If the type is polymorphic then we have two cases: if
 
                        // the programmer did not specify the polyargs then we
 
                        // assume we're going to infer all of them. Otherwise we
 
                        // make sure that they match in count.
 
                        if !found_type.poly_args.is_empty() && symbolic.poly_args.is_empty() {
 
                            // All inferred
 
                            (
 
                                symbolic.identifier.position,
 
                                SymbolicParserTypeVariant::Definition(found_type.ast_definition),
 
                                found_type.poly_args.len()
 
                            )
 
                        } else if symbolic.poly_args.len() != found_type.poly_args.len() {
 
                            return Err(ParseError2::new_error(
 
                                &ctx.module.source, symbolic.identifier.position,
 
                                &format!(
 
                                    "Expected {} polymorphic arguments (or none, to infer them), but {} were specified",
 
                                    found_type.poly_args.len(), symbolic.poly_args.len()
 
                                )
 
                            ))
 
                        } else {
 
                            // If here then the type is not polymorphic, or all
 
                            // types are properly specified by the user.
 
                            for specified_poly_arg in &symbolic.poly_args {
 
                                self.parser_type_buffer.push(*specified_poly_arg);
 
                            }
 

	
 
                            (
 
                                symbolic.identifier.position,
 
                                SymbolicParserTypeVariant::Definition(found_type.ast_definition),
 
                                0
 
                            )
 
                        }
 
                    }
 
                }
 
            };
 

	
 
            // If here then type is symbolic, perform a mutable borrow to set
 
            // the target of the symbolic type.
 
            for _ in 0..num_inferred_to_allocate {
 
                // TODO: @hack, not very user friendly to manually allocate
 
                //  `inferred` ParserTypes with the InputPosition of the
src/protocol/tests/lexer.rs
Show inline comments
 
new file 100644
 
/// lexer.rs
 
///
 
/// Simple tests for the lexer. Only tests the lexing of the input source and
 
/// the resulting AST without relying on the validation/typing pass
 

	
 
use super::*;
 

	
 
#[test]
 
fn test_disallowed_inference() {
 
    Tester::new_single_source_expect_err(
 
        "argument auto inference",
 
            "int func(auto arg) { return 0; }"
 
    ).error(|e| { e
 
        .assert_msg_has(0, "inference is not allowed")
 
        .assert_occurs_at(0, "auto arg");
 
    });
 

	
 
    Tester::new_single_source_expect_err(
 
        "return type auto inference",
 
        "auto func(int arg) { return 0; }"
 
    ).error(|e| { e
 
        .assert_msg_has(0, "inference is not allowed")
 
        .assert_occurs_at(0, "auto func");
 
    });
 

	
 
    Tester::new_single_source_expect_err(
 
        "implicit polymorph argument auto inference",
 
        "int func(in port) { return port; }"
 
    ).error(|e| { e
 
        .assert_msg_has(0, "inference is not allowed")
 
        .assert_occurs_at(0, "in port");
 
    });
 

	
 
    Tester::new_single_source_expect_err(
 
        "explicit polymorph argument auto inference",
 
        "int func(in<auto> port) { return port; }"
 
    ).error(|e| { e
 
        .assert_msg_has(0, "inference is not allowed")
 
        .assert_occurs_at(0, "auto> port");
 
    });
 

	
 
    Tester::new_single_source_expect_err(
 
        "implicit polymorph return type auto inference",
 
        "in func(in<msg> a, in<msg> b) { return a; }"
 
    ).error(|e| { e
 
        .assert_msg_has(0, "inference is not allowed")
 
        .assert_occurs_at(0, "in func");
 
    });
 

	
 
    Tester::new_single_source_expect_err(
 
        "explicit polymorph return type auto inference",
 
        "in<auto> func(in<msg> a) { return a; }"
 
    ).error(|e| { e
 
        .assert_msg_has(0, "inference is not allowed")
 
        .assert_occurs_at(0, "auto> func");
 
    });
 
}
 

	
 
#[test]
 
fn test_simple_struct_definition() {
 
    Tester::new_single_source_expect_ok(
 
        "empty struct",
 
        "struct Foo{}"
 
    ).for_struct("Foo", |t| { t.assert_num_fields(0); });
 

	
 
    Tester::new_single_source_expect_ok(
 
        "single field, no comma",
 
        "struct Foo{ int field }"
 
    ).for_struct("Foo", |t| { t
 
        .assert_num_fields(1)
 
        .for_field("field", |f| {
 
            f.assert_parser_type("int");
 
        });
 
    });
 

	
 
    Tester::new_single_source_expect_ok(
 
        "single field, with comma",
 
        "struct Foo{ int field, }"
 
    ).for_struct("Foo", |t| { t
 
        .assert_num_fields(1)
 
        .for_field("field", |f| { f
 
            .assert_parser_type("int");
 
        });
 
    });
 

	
 
    Tester::new_single_source_expect_ok(
 
        "multiple fields, no comma",
 
        "struct Foo{ byte a, short b, int c }"
 
    ).for_struct("Foo", |t| { t
 
        .assert_num_fields(3)
 
        .for_field("a", |f| { f.assert_parser_type("byte"); })
 
        .for_field("b", |f| { f.assert_parser_type("short"); })
 
        .for_field("c", |f| { f.assert_parser_type("int"); });
 
    });
 

	
 
    Tester::new_single_source_expect_ok(
 
        "multiple fields, with comma",
 
        "struct Foo{
 
            byte a,
 
            short b,
 
            int c,
 
        }"
 
    ).for_struct("Foo", |t| { t
 
        .assert_num_fields(3)
 
        .for_field("a", |f| { f.assert_parser_type("byte"); })
 
        .for_field("b", |f| { f.assert_parser_type("short"); })
 
        .for_field("c", |f| { f.assert_parser_type("int"); });
 
    });
 
}
 
\ No newline at end of file
src/protocol/tests/mod.rs
Show inline comments
 
new file 100644
 
mod utils;
 
mod lexer;
 

	
 
pub(crate) use utils::{Tester};
 
\ No newline at end of file
src/protocol/tests/utils.rs
Show inline comments
 
new file 100644
 
use crate::protocol::ast::*;
 
use crate::protocol::inputsource::*;
 
use crate::protocol::parser::*;
 

	
 
//------------------------------------------------------------------------------
 
// Interface for parsing and compiling
 
//------------------------------------------------------------------------------
 

	
 
pub(crate) struct Tester {
 
    test_name: String,
 
    sources: Vec<String>
 
}
 

	
 
impl Tester {
 
    /// Constructs a new tester, allows adding multiple sources before compiling
 
    pub(crate) fn new<S: ToString>(test_name: S) -> Self {
 
        Self{
 
            test_name: test_name.to_string(),
 
            sources: Vec::new()
 
        }
 
    }
 

	
 
    /// Utility for quick tests that use a single source file and expect the
 
    /// compilation to succeed.
 
    pub(crate) fn new_single_source_expect_ok<T: ToString, S: ToString>(test_name: T, source: S) -> AstOkTester {
 
        Self::new(test_name)
 
            .with_source(source)
 
            .compile()
 
            .expect_ok()
 
    }
 

	
 
    /// Utility for quick tests that use a single source file and expect the
 
    /// compilation to fail.
 
    pub(crate) fn new_single_source_expect_err<T: ToString, S: ToString>(test_name: T, source: S) -> AstErrTester {
 
        Self::new(test_name)
 
            .with_source(source)
 
            .compile()
 
            .expect_err()
 
    }
 

	
 
    pub(crate) fn with_source<S: ToString>(mut self, source: S) -> Self {
 
        self.sources.push(source.to_string());
 
        self
 
    }
 

	
 
    pub(crate) fn compile(self) -> AstTesterResult {
 
        let mut parser = Parser::new();
 
        for (source_idx, source) in self.sources.into_iter().enumerate() {
 
            let mut cursor = std::io::Cursor::new(source);
 
            let input_source = InputSource::new("", &mut cursor)
 
                .expect(&format!("parsing source {}", source_idx + 1));
 

	
 
            if let Err(err) = parser.feed(input_source) {
 
                return AstTesterResult::Err(AstErrTester::new(self.test_name, err))
 
            }
 
        }
 

	
 
        parser.compile();
 
        if let Err(err) = parser.parse() {
 
            return AstTesterResult::Err(AstErrTester::new(self.test_name, err))
 
        }
 

	
 
        AstTesterResult::Ok(AstOkTester::new(self.test_name, parser))
 
    }
 
}
 

	
 
pub(crate) enum AstTesterResult {
 
    Ok(AstOkTester),
 
    Err(AstErrTester)
 
}
 

	
 
impl AstTesterResult {
 
    pub(crate) fn expect_ok(self) -> AstOkTester {
 
        match self {
 
            AstTesterResult::Ok(v) => v,
 
            AstTesterResult::Err(err) => {
 
                let wrapped = ErrorTester{ test_name: &err.test_name, error: &err.error };
 
                assert!(
 
                    false,
 
                    "[{}] Expected compilation to succeed, but it failed with {}",
 
                    err.test_name, wrapped.assert_postfix()
 
                );
 
                unreachable!();
 
            }
 
        }
 
    }
 

	
 
    pub(crate) fn expect_err(self) -> AstErrTester {
 
        match self {
 
            AstTesterResult::Ok(ok) => {
 
                assert!(false, "[{}] Expected compilation to fail, but it succeeded", ok.test_name);
 
                unreachable!();
 
            },
 
            AstTesterResult::Err(err) => err,
 
        }
 
    }
 
}
 

	
 
//------------------------------------------------------------------------------
 
// Interface for successful compilation
 
//------------------------------------------------------------------------------
 

	
 
pub(crate) struct AstOkTester {
 
    test_name: String,
 
    modules: Vec<LexedModule>,
 
    heap: Heap,
 
}
 

	
 
impl AstOkTester {
 
    fn new(test_name: String, parser: Parser) -> Self {
 
        Self {
 
            test_name,
 
            modules: parser.modules,
 
            heap: parser.heap
 
        }
 
    }
 

	
 
    pub(crate) fn for_struct<F: Fn(StructTester)>(self, name: &str, f: F) -> Self {
 
        let mut found = false;
 
        for definition in self.heap.definitions.iter() {
 
            if let Definition::Struct(definition) = definition {
 
                if String::from_utf8_lossy(&definition.identifier.value) != name {
 
                    continue;
 
                }
 

	
 
                // Found struct with the same name
 
                let tester = StructTester::new(&self.test_name, definition, &self.heap);
 
                f(tester);
 
                found = true;
 
                break
 
            }
 
        }
 

	
 
        if found { return self }
 

	
 
        assert!(
 
            false, "[{}] Failed to find definition for struct '{}'",
 
            self.test_name, name
 
        );
 
        unreachable!()
 
    }
 
}
 

	
 
//------------------------------------------------------------------------------
 
// Utilities for successful compilation
 
//------------------------------------------------------------------------------
 

	
 
pub(crate) struct StructTester<'a> {
 
    test_name: &'a str,
 
    def: &'a StructDefinition,
 
    heap: &'a Heap,
 
}
 

	
 
impl<'a> StructTester<'a> {
 
    fn new(test_name: &'a str, def: &'a StructDefinition, heap: &'a Heap) -> Self {
 
        Self{ test_name, def, heap }
 
    }
 

	
 
    pub(crate) fn assert_num_fields(self, num: usize) -> Self {
 
        debug_assert_eq!(
 
            num, self.def.fields.len(),
 
            "[{}] Expected {} struct fields, but found {} for {}",
 
            self.test_name, num, self.def.fields.len(), self.assert_postfix()
 
        );
 
        self
 
    }
 

	
 
    pub(crate) fn for_field<F: Fn(StructFieldTester)>(self, name: &str, f: F) -> Self {
 
        // Find field with specified name
 
        for field in &self.def.fields {
 
            if String::from_utf8_lossy(&field.field.value) == name {
 
                let tester = StructFieldTester::new(self.test_name, field, self.heap);
 
                f(tester);
 
                return self;
 
            }
 
        }
 

	
 
        assert!(
 
            false, "[{}] Could not find struct field '{}' for {}",
 
            self.test_name, name, self.assert_postfix()
 
        );
 
        unreachable!();
 
    }
 

	
 
    fn assert_postfix(&self) -> String {
 
        let mut v = String::new();
 
        v.push_str("Struct{ name: ");
 
        v.push_str(&String::from_utf8_lossy(&self.def.identifier.value));
 
        v.push_str(", fields: [");
 
        for (field_idx, field) in self.def.fields.iter().enumerate() {
 
            if field_idx != 0 { v.push_str(", "); }
 
            v.push_str(&String::from_utf8_lossy(&field.field.value));
 
        }
 
        v.push_str("] }");
 
        v
 
    }
 
}
 

	
 
pub(crate) struct StructFieldTester<'a> {
 
    test_name: &'a str,
 
    def: &'a StructFieldDefinition,
 
    heap: &'a Heap,
 
}
 

	
 
impl<'a> StructFieldTester<'a> {
 
    fn new(test_name: &'a str, def: &'a StructFieldDefinition, heap: &'a Heap) -> Self {
 
        Self{ test_name, def, heap }
 
    }
 

	
 
    pub(crate) fn assert_parser_type(self, expected: &str) -> Self {
 
        let mut serialized_type = String::new();
 
        serialize_parser_type(&mut serialized_type, &self.heap, self.def.parser_type);
 
        debug_assert_eq!(
 
            expected, &serialized_type,
 
            "[{}] Expected type '{}', but got '{}' for {}",
 
            self.test_name, expected, &serialized_type, self.assert_postfix()
 
        );
 
        self
 
    }
 

	
 
    fn assert_postfix(&self) -> String {
 
        let mut serialized_type = String::new();
 
        serialize_parser_type(&mut serialized_type, &self.heap, self.def.parser_type);
 
        format!(
 
            "StructField{{ name: {}, parser_type: {} }}",
 
            String::from_utf8_lossy(&self.def.field.value), serialized_type
 
        )
 
    }
 
}
 

	
 
//------------------------------------------------------------------------------
 
// Interface for failed compilation
 
//------------------------------------------------------------------------------
 

	
 
pub(crate) struct AstErrTester {
 
    test_name: String,
 
    error: ParseError2,
 
}
 

	
 
impl AstErrTester {
 
    fn new(test_name: String, error: ParseError2) -> Self {
 
        Self{ test_name, error }
 
    }
 

	
 
    pub(crate) fn error<F: Fn(ErrorTester)>(&self, f: F) {
 
        // Maybe multiple errors will be supported in the future
 
        let tester = ErrorTester{ test_name: &self.test_name, error: &self.error };
 
        f(tester)
 
    }
 
}
 

	
 
//------------------------------------------------------------------------------
 
// Utilities for failed compilation
 
//------------------------------------------------------------------------------
 

	
 
pub(crate) struct ErrorTester<'a> {
 
    test_name: &'a str,
 
    error: &'a ParseError2,
 
}
 

	
 
impl<'a> ErrorTester<'a> {
 
    pub(crate) fn assert_num(self, num: usize) -> Self {
 
        assert_eq!(
 
            num, self.error.statements.len(),
 
            "[{}] expected error to consist of '{}' parts, but encountered '{}' for {}",
 
            self.test_name, num, self.error.statements.len(), self.assert_postfix()
 
        );
 

	
 
        self
 
    }
 

	
 
    pub(crate) fn assert_ctx_has(self, idx: usize, msg: &str) -> Self {
 
        assert!(
 
            self.error.statements[idx].context.contains(msg),
 
            "[{}] expected error statement {}'s context to contain '{}' for {}",
 
            self.test_name, idx, msg, self.assert_postfix()
 
        );
 

	
 
        self
 
    }
 

	
 
    pub(crate) fn assert_msg_has(self, idx: usize, msg: &str) -> Self {
 
        assert!(
 
            self.error.statements[idx].message.contains(msg),
 
            "[{}] expected error statement {}'s message to contain '{}' for {}",
 
            self.test_name, idx, msg, self.assert_postfix()
 
        );
 

	
 
        self
 
    }
 

	
 
    /// Seeks the index of the pattern in the context message, then checks if
 
    /// the input position corresponds to that index.
 
    pub (crate) fn assert_occurs_at(self, idx: usize, pattern: &str) -> Self {
 
        let pos = self.error.statements[idx].context.find(pattern);
 
        assert!(
 
            pos.is_some(),
 
            "[{}] incorrect occurs_at: '{}' could not be found in the context for {}",
 
            self.test_name, pattern, self.assert_postfix()
 
        );
 
        let pos = pos.unwrap();
 
        let col = self.error.statements[idx].position.col();
 
        assert_eq!(
 
            pos + 1, col,
 
            "[{}] Expected error to occur at column {}, but found it at {} for {}",
 
            self.test_name, pos + 1, col, self.assert_postfix()
 
        );
 

	
 
        self
 
    }
 

	
 
    fn assert_postfix(&self) -> String {
 
        let mut v = String::new();
 
        v.push_str("error: [");
 
        for (idx, stmt) in self.error.statements.iter().enumerate() {
 
            if idx != 0 {
 
                v.push_str(", ");
 
            }
 

	
 
            v.push_str(&format!("{{ context: {}, message: {} }}", &stmt.context, stmt.message));
 
        }
 
        v.push(']');
 
        v
 
    }
 
}
 

	
 
//------------------------------------------------------------------------------
 
// Generic utilities
 
//------------------------------------------------------------------------------
 

	
 
fn serialize_parser_type(buffer: &mut String, heap: &Heap, id: ParserTypeId) {
 
    use ParserTypeVariant as PTV;
 

	
 
    let p = &heap[id];
 
    match &p.variant {
 
        PTV::Message => buffer.push_str("msg"),
 
        PTV::Bool => buffer.push_str("bool"),
 
        PTV::Byte => buffer.push_str("byte"),
 
        PTV::Short => buffer.push_str("short"),
 
        PTV::Int => buffer.push_str("int"),
 
        PTV::Long => buffer.push_str("long"),
 
        PTV::String => buffer.push_str("string"),
 
        PTV::IntegerLiteral => buffer.push_str("intlit"),
 
        PTV::Inferred => buffer.push_str("auto"),
 
        PTV::Array(sub_id) => {
 
            serialize_parser_type(buffer, heap, *sub_id);
 
            buffer.push_str("[]");
 
        },
 
        PTV::Input(sub_id) => {
 
            buffer.push_str("in<");
 
            serialize_parser_type(buffer, heap, *sub_id);
 
            buffer.push('>');
 
        },
 
        PTV::Output(sub_id) => {
 
            buffer.push_str("out<");
 
            serialize_parser_type(buffer, heap, *sub_id);
 
            buffer.push('>');
 
        },
 
        PTV::Symbolic(symbolic) => {
 
            buffer.push_str(&String::from_utf8_lossy(&symbolic.identifier.value));
 
            if symbolic.poly_args.len() > 0 {
 
                buffer.push('<');
 
                for (poly_idx, poly_arg) in symbolic.poly_args.iter().enumerate() {
 
                    if poly_idx != 0 { buffer.push(','); }
 
                    serialize_parser_type(buffer, heap, *poly_arg);
 
                }
 
                buffer.push('>');
 
            }
 
        }
 
    }
 
}
 
\ No newline at end of file
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