Changeset - c2e3074a729b
[Not reviewed]
0 20 0
mh - 3 years ago 2022-04-13 13:35:29
contact@maxhenger.nl
Implement byte string, TCP socket, HTTP request test. Fix escape character parsing. Refactor component code
8 files changed:
0 comments (0 inline, 0 general)
src/collections/scoped_buffer.rs
Show inline comments
 
/// scoped_buffer.rs
 
///
 
/// Solves the common pattern where we are performing some kind of recursive
 
/// pattern while using a temporary buffer. At the start, or during the
 
/// procedure, we push stuff into the buffer. At the end we take out what we
 
/// have put in.
 
///
 
/// It is unsafe because we're using pointers to circumvent borrowing rules in
 
/// the name of code cleanliness. The correctness of use is checked in debug
 
/// mode at runtime.
 

	
 
use std::iter::FromIterator;
 

	
 
macro_rules! hide {
 
    ($v:block) => {
 
        #[cfg(debug_assertions)] $v
 
    };
 
    ($v:expr) => {
 
        #[cfg(debug_assertions)] $v
 
    };
 
}
 

	
 
pub(crate) struct ScopedBuffer<T: Sized> {
 
    pub inner: Vec<T>,
 
}
 

	
 
impl<T: Sized> ScopedBuffer<T> {
 
    pub(crate) fn with_capacity(capacity: usize) -> Self {
 
        Self {
 
            inner: Vec::with_capacity(capacity),
 
        }
 
    }
 

	
 
    pub(crate) fn start_section(&mut self) -> ScopedSection<T> {
 
        let start_size = self.inner.len() as u32;
 
        ScopedSection {
 
            inner: &mut self.inner,
 
            start_size,
 
            #[cfg(debug_assertions)] cur_size: start_size,
 
        }
 
    }
 
}
 

	
 
impl<T: Clone> ScopedBuffer<T> {
 
    pub(crate) fn start_section_initialized(&mut self, initialize_with: &[T]) -> ScopedSection<T> {
 
        let start_size = self.inner.len() as u32;
 
        let _data_size = initialize_with.len() as u32;
 
        self.inner.extend_from_slice(initialize_with);
 
        ScopedSection{
 
            inner: &mut self.inner,
 
            start_size,
 
            #[cfg(debug_assertions)] cur_size: start_size + _data_size,
 
        }
 
    }
 
}
 

	
 
#[cfg(debug_assertions)]
 
impl<T: Sized> Drop for ScopedBuffer<T> {
 
    fn drop(&mut self) {
 
        // Make sure that everyone cleaned up the buffer neatly
 
        debug_assert!(self.inner.is_empty(), "dropped non-empty scoped buffer");
 
    }
 
}
 

	
 
/// A section of the buffer. Keeps track of where we started the section. When
 
/// done with the section one must call `into_vec` or `forget` to remove the
 
/// section from the underlying buffer. This will also be done upon dropping the
 
/// ScopedSection in case errors are being handled.
 
pub(crate) struct ScopedSection<T: Sized> {
 
    inner: *mut Vec<T>,
 
    start_size: u32,
 
    #[cfg(debug_assertions)] cur_size: u32,
 
}
 

	
 
impl<T: Sized> ScopedSection<T> {
 
    /// Pushes value into section
 
    #[inline]
 
    pub(crate) fn push(&mut self, value: T) {
 
        self.check_length();
 
        let vec = unsafe{&mut *self.inner};
 
        vec.push(value);
 
        hide!(self.cur_size += 1);
 
    }
 

	
 
    #[inline]
 
    pub(crate) fn len(&self) -> usize {
 
        self.check_length();
 
        let vec = unsafe{&mut *self.inner};
 
        return vec.len() - self.start_size as usize;
 
    }
 

	
 
    #[inline]
 
    #[allow(unused_mut)] // used in debug mode
 
    pub(crate) fn forget(mut self) {
 
        self.check_length();
 
        let vec = unsafe{&mut *self.inner};
 
        hide!(self.cur_size = self.start_size);
 
        vec.truncate(self.start_size as usize);
 
    }
 

	
 
    #[inline]
 
    #[allow(unused_mut)] // used in debug mode
 
    pub(crate) fn into_vec(mut self) -> Vec<T> {
 
        self.check_length();
 
        let vec = unsafe{&mut *self.inner};
 
        hide!(self.cur_size = self.start_size);
 
        let section = Vec::from_iter(vec.drain(self.start_size as usize..));
 
        section
 
    }
 

	
 
    #[inline]
 
    pub(crate) fn check_length(&self) {
 
        hide!({
 
            let vec = unsafe{&*self.inner};
 
            debug_assert_eq!(
 
                vec.len(), self.cur_size as usize,
 
                "incorrect use of ScopedSection: underlying storage vector has changed size"
 
            )
 
        })
 
    }
 
}
 

	
 
impl<T: Sized + PartialEq> ScopedSection<T> {
 
    #[inline]
 
    pub(crate) fn push_unique(&mut self, value: T) {
 
        self.check_length();
 
        let vec = unsafe{&mut *self.inner};
 
        for item in &vec[self.start_size as usize..] {
 
            if *item == value {
 
                // item already exists
 
                return;
 
            }
 
        }
 

	
 
        vec.push(value);
 
        hide!(self.cur_size += 1);
 
    }
 

	
 
    #[inline]
 
    pub(crate) fn contains(&self, value: &T) -> bool {
 
        self.check_length();
 
        let vec = unsafe{&*self.inner};
 
        for index in self.start_size as usize..vec.len() {
 
            if &vec[index] == value {
 
                return true;
 
            }
 
        }
 

	
 
        return false;
 
    }
 
}
 

	
 
impl<T: Copy> ScopedSection<T> {
 
    pub(crate) fn iter_copied(&self) -> ScopedIter<T> {
 
        return ScopedIter{
 
            inner: self.inner,
 
            cur_index: self.start_size,
 
            last_index: unsafe{ (*self.inner).len() as u32 },
 
        }
 
    }
 
}
 

	
 
impl<T> std::ops::Index<usize> for ScopedSection<T> {
 
    type Output = T;
 

	
 
    fn index(&self, index: usize) -> &Self::Output {
 
        let vec = unsafe{&*self.inner};
 
        return &vec[self.start_size as usize + index]
 
    }
 
}
 

	
 
impl<T> std::ops::IndexMut<usize> for ScopedSection<T> {
 
    fn index_mut(&mut self, index: usize) -> &mut Self::Output {
 
        let vec = unsafe{&mut *self.inner};
 
        return &mut vec[self.start_size as usize + index]
 
    }
 
}
 

	
 
#[cfg(debug_assertions)]
 
// note: this `Drop` impl used to be debug-only, requiring the programmer to
 
// call `into_vec` or `forget`. But this is rather error prone. So we'll check
 
// in debug mode, but always truncate in release mode (even though this is a
 
// noop in most cases).
 
impl<T: Sized> Drop for ScopedSection<T> {
 
    fn drop(&mut self) {
 
        let vec = unsafe{&mut *self.inner};
 
        hide!(debug_assert_eq!(vec.len(), self.cur_size as usize));
 
        vec.truncate(self.start_size as usize);
 
    }
 
}
 

	
 
/// Small utility for iterating over a section of the buffer. Same conditions as
 
/// the buffer apply: each time we retrieve an element the buffer must have the
 
/// same size as the moment of creation.
 
pub(crate) struct ScopedIter<T: Copy> {
 
    inner: *mut Vec<T>,
 
    cur_index: u32,
 
    last_index: u32,
 
}
 

	
 
impl<T: Copy> Iterator for ScopedIter<T> {
 
    type Item = T;
 

	
 
    fn next(&mut self) -> Option<Self::Item> {
 
        hide!(debug_assert_eq!(self.last_index as usize, unsafe { (*self.inner).len() }));
 
        if self.cur_index >= self.last_index {
 
            return None;
 
        }
 

	
 
        let vec = unsafe{ &*self.inner };
 
        let index = self.cur_index as usize;
 
        self.cur_index += 1;
 
        return Some(vec[index]);
 
    }
 
}
 
\ No newline at end of file
src/protocol/ast.rs
Show inline comments
 
@@ -1707,283 +1707,284 @@ pub enum BinaryOperator {
 
    BitwiseXor,
 
    BitwiseAnd,
 
    Equality,
 
    Inequality,
 
    LessThan,
 
    GreaterThan,
 
    LessThanEqual,
 
    GreaterThanEqual,
 
    ShiftLeft,
 
    ShiftRight,
 
    Add,
 
    Subtract,
 
    Multiply,
 
    Divide,
 
    Remainder,
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub struct BinaryExpression {
 
    pub this: BinaryExpressionId,
 
    // Parsing
 
    pub operator_span: InputSpan,
 
    pub full_span: InputSpan,
 
    pub left: ExpressionId,
 
    pub operation: BinaryOperator,
 
    pub right: ExpressionId,
 
    // Validator/Linker
 
    pub parent: ExpressionParent,
 
    // Typing
 
    pub type_index: i32,
 
}
 

	
 
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
 
pub enum UnaryOperator {
 
    Positive,
 
    Negative,
 
    BitwiseNot,
 
    LogicalNot,
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub struct UnaryExpression {
 
    pub this: UnaryExpressionId,
 
    // Parsing
 
    pub operator_span: InputSpan,
 
    pub full_span: InputSpan,
 
    pub operation: UnaryOperator,
 
    pub expression: ExpressionId,
 
    // Validator/Linker
 
    pub parent: ExpressionParent,
 
    // Typing
 
    pub type_index: i32,
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub struct IndexingExpression {
 
    pub this: IndexingExpressionId,
 
    // Parsing
 
    pub operator_span: InputSpan,
 
    pub full_span: InputSpan,
 
    pub subject: ExpressionId,
 
    pub index: ExpressionId,
 
    // Validator/Linker
 
    pub parent: ExpressionParent,
 
    // Typing
 
    pub type_index: i32,
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub struct SlicingExpression {
 
    pub this: SlicingExpressionId,
 
    // Parsing
 
    pub slicing_span: InputSpan, // from '[' to ']'
 
    pub full_span: InputSpan, // includes subject
 
    pub subject: ExpressionId,
 
    pub from_index: ExpressionId,
 
    pub to_index: ExpressionId,
 
    // Validator/Linker
 
    pub parent: ExpressionParent,
 
    // Typing
 
    pub type_index: i32,
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub enum SelectKind {
 
    StructField(Identifier),
 
    TupleMember(u64), // u64 is overkill, but space is taken up by `StructField` variant anyway
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub struct SelectExpression {
 
    pub this: SelectExpressionId,
 
    // Parsing
 
    pub operator_span: InputSpan, // of the '.'
 
    pub full_span: InputSpan, // includes subject and field
 
    pub subject: ExpressionId,
 
    pub kind: SelectKind,
 
    // Validator/Linker
 
    pub parent: ExpressionParent,
 
    // Typing
 
    pub type_index: i32,
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub struct CastExpression {
 
    pub this: CastExpressionId,
 
    // Parsing
 
    pub cast_span: InputSpan, // of the "cast" keyword,
 
    pub full_span: InputSpan, // includes the cast subject
 
    pub to_type: ParserType,
 
    pub subject: ExpressionId,
 
    // Validator/linker
 
    pub parent: ExpressionParent,
 
    // Typing
 
    pub type_index: i32,
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub struct CallExpression {
 
    pub this: CallExpressionId,
 
    // Parsing
 
    pub func_span: InputSpan, // of the function name
 
    pub full_span: InputSpan, // includes the arguments and parentheses
 
    pub parser_type: ParserType, // of the function call, not the return type
 
    pub method: Method,
 
    pub arguments: Vec<ExpressionId>,
 
    pub procedure: ProcedureDefinitionId,
 
    // Validator/Linker
 
    pub parent: ExpressionParent,
 
    // Typing
 
    pub type_index: i32,
 
}
 

	
 
#[derive(Debug, Clone, PartialEq, Eq)]
 
pub enum Method {
 
    // Builtin function, accessible by programmer
 
    Get,
 
    Put,
 
    Fires,
 
    Create,
 
    Length,
 
    Assert,
 
    Print,
 
    // Builtin function, not accessible by programmer
 
    SelectStart, // SelectStart(total_num_cases, total_num_ports)
 
    SelectRegisterCasePort, // SelectRegisterCasePort(case_index, port_index, port_id)
 
    SelectWait, // SelectWait() -> u32
 
    // Builtin component,
 
    ComponentRandomU32,
 
    ComponentTcpClient,
 
    // User-defined
 
    UserFunction,
 
    UserComponent,
 
}
 

	
 
impl Method {
 
    pub(crate) fn is_public_builtin(&self) -> bool {
 
        use Method::*;
 
        match self {
 
            Get | Put | Fires | Create | Length | Assert | Print => true,
 
            ComponentRandomU32 | ComponentTcpClient => true,
 
            _ => false,
 
        }
 
    }
 

	
 
    pub(crate) fn is_user_defined(&self) -> bool {
 
        use Method::*;
 
        match self {
 
            UserFunction | UserComponent => true,
 
            _ => false,
 
        }
 
    }
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub struct LiteralExpression {
 
    pub this: LiteralExpressionId,
 
    // Parsing
 
    pub span: InputSpan,
 
    pub value: Literal,
 
    // Validator/Linker
 
    pub parent: ExpressionParent,
 
    // Typing
 
    pub type_index: i32,
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub enum Literal {
 
    Null, // message
 
    True,
 
    False,
 
    Character(char),
 
    Bytestring(Vec<u8>),
 
    String(StringRef<'static>),
 
    Integer(LiteralInteger),
 
    Struct(LiteralStruct),
 
    Enum(LiteralEnum),
 
    Union(LiteralUnion),
 
    Array(Vec<ExpressionId>),
 
    Tuple(Vec<ExpressionId>),
 
}
 

	
 
impl Literal {
 
    pub(crate) fn as_struct(&self) -> &LiteralStruct {
 
        if let Literal::Struct(literal) = self{
 
            literal
 
        } else {
 
            unreachable!("Attempted to obtain {:?} as Literal::Struct", self)
 
        }
 
    }
 

	
 
    pub(crate) fn as_enum(&self) -> &LiteralEnum {
 
        if let Literal::Enum(literal) = self {
 
            literal
 
        } else {
 
            unreachable!("Attempted to obtain {:?} as Literal::Enum", self)
 
        }
 
    }
 

	
 
    pub(crate) fn as_union(&self) -> &LiteralUnion {
 
        if let Literal::Union(literal) = self {
 
            literal
 
        } else {
 
            unreachable!("Attempted to obtain {:?} as Literal::Union", self)
 
        }
 
    }
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub struct LiteralInteger {
 
    pub(crate) unsigned_value: u64,
 
    pub(crate) negated: bool, // for constant expression evaluation, TODO: @Int
 
}
 

	
 
#[derive(Debug, Clone)]
 
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)]
 
pub struct LiteralStruct {
 
    // Phase 1: parser
 
    pub(crate) parser_type: ParserType,
 
    pub(crate) fields: Vec<LiteralStructField>,
 
    pub(crate) definition: DefinitionId,
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub struct LiteralEnum {
 
    // Phase 1: parser
 
    pub(crate) parser_type: ParserType,
 
    pub(crate) variant: Identifier,
 
    pub(crate) definition: DefinitionId,
 
    // Phase 2: linker
 
    pub(crate) variant_idx: usize, // as present in the type table
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub struct LiteralUnion {
 
    // Phase 1: parser
 
    pub(crate) parser_type: ParserType,
 
    pub(crate) variant: Identifier,
 
    pub(crate) values: Vec<ExpressionId>,
 
    pub(crate) definition: DefinitionId,
 
    // Phase 2: linker
 
    pub(crate) variant_idx: usize, // as present in type table
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub struct VariableExpression {
 
    pub this: VariableExpressionId,
 
    // Parsing
 
    pub identifier: Identifier,
 
    // Validator/Linker
 
    pub declaration: Option<VariableId>,
 
    pub used_as_binding_target: bool,
 
    pub parent: ExpressionParent,
 
    // Typing
 
    pub type_index: i32,
 
}
 
\ No newline at end of file
src/protocol/ast_writer.rs
Show inline comments
 
@@ -176,704 +176,713 @@ pub(crate) struct ASTWriter {
 
    buffer: String,
 
    temp1: String,
 
    temp2: String,
 
}
 

	
 
impl ASTWriter {
 
    pub(crate) fn new() -> Self {
 
        Self{
 
            cur_definition: None,
 
            buffer: String::with_capacity(4096),
 
            temp1: String::with_capacity(256),
 
            temp2: String::with_capacity(256),
 
        }
 
    }
 
    pub(crate) fn write_ast<W: IOWrite>(&mut self, w: &mut W, heap: &Heap) {
 
        for root_id in heap.protocol_descriptions.iter().map(|v| v.this) {
 
            self.write_module(heap, root_id);
 
            w.write_all(self.buffer.as_bytes()).expect("flush buffer");
 
            self.buffer.clear();
 
        }
 
    }
 

	
 
    //--------------------------------------------------------------------------
 
    // Top-level module writing
 
    //--------------------------------------------------------------------------
 

	
 
    fn write_module(&mut self, heap: &Heap, root_id: RootId) {
 
        self.kv(0).with_id(PREFIX_ROOT_ID, root_id.index)
 
            .with_s_key("Module");
 

	
 
        let root = &heap[root_id];
 
        self.kv(1).with_s_key("Pragmas");
 
        for pragma_id in &root.pragmas {
 
            self.write_pragma(heap, *pragma_id, 2);
 
        }
 

	
 
        self.kv(1).with_s_key("Imports");
 
        for import_id in &root.imports {
 
            self.write_import(heap, *import_id, 2);
 
        }
 

	
 
        self.kv(1).with_s_key("Definitions");
 
        for def_id in &root.definitions {
 
            self.write_definition(heap, *def_id, 2);
 
        }
 
    }
 

	
 
    fn write_pragma(&mut self, heap: &Heap, pragma_id: PragmaId, indent: usize) {
 
        match &heap[pragma_id] {
 
            Pragma::Version(pragma) => {
 
                self.kv(indent).with_id(PREFIX_PRAGMA_ID, pragma.this.index)
 
                    .with_s_key("PragmaVersion")
 
                    .with_disp_val(&pragma.version);
 
            },
 
            Pragma::Module(pragma) => {
 
                self.kv(indent).with_id(PREFIX_PRAGMA_ID, pragma.this.index)
 
                    .with_s_key("PragmaModule")
 
                    .with_identifier_val(&pragma.value);
 
            }
 
        }
 
    }
 

	
 
    fn write_import(&mut self, heap: &Heap, import_id: ImportId, indent: usize) {
 
        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_identifier_val(&import.module);
 
                self.kv(indent2).with_s_key("Alias").with_identifier_val(&import.alias);
 
                self.kv(indent2).with_s_key("Target").with_disp_val(&import.module_id.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_identifier_val(&import.module);
 
                self.kv(indent2).with_s_key("Target").with_disp_val(&import.module_id.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_identifier_val(&symbol.name);
 
                    self.kv(indent4).with_s_key("Alias").with_opt_identifier_val(symbol.alias.as_ref());
 
                    self.kv(indent4).with_s_key("Definition").with_disp_val(&symbol.definition_id.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(def) => {
 
                self.kv(indent).with_id(PREFIX_STRUCT_ID, def.this.0.index)
 
                    .with_s_key("DefinitionStruct");
 

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

	
 
                self.kv(indent2).with_s_key("Fields");
 
                for field in &def.fields {
 
                    self.kv(indent3).with_s_key("Field");
 
                    self.kv(indent4).with_s_key("Name")
 
                        .with_identifier_val(&field.field);
 
                    self.kv(indent4).with_s_key("Type")
 
                        .with_custom_val(|s| write_parser_type(s, heap, &field.parser_type));
 
                }
 
            },
 
            Definition::Enum(def) => {
 
                self.kv(indent).with_id(PREFIX_ENUM_ID, def.this.0.index)
 
                    .with_s_key("DefinitionEnum");
 

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

	
 
                self.kv(indent2).with_s_key("Variants");
 
                for variant in &def.variants {
 
                    self.kv(indent3).with_s_key("Variant");
 
                    self.kv(indent4).with_s_key("Name")
 
                        .with_identifier_val(&variant.identifier);
 
                    let variant_value = self.kv(indent4).with_s_key("Value");
 
                    match &variant.value {
 
                        EnumVariantValue::None => variant_value.with_s_val("None"),
 
                        EnumVariantValue::Integer(value) => variant_value.with_disp_val(value),
 
                    };
 
                }
 
            },
 
            Definition::Union(def) => {
 
                self.kv(indent).with_id(PREFIX_UNION_ID, def.this.0.index)
 
                    .with_s_key("DefinitionUnion");
 

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

	
 
                self.kv(indent2).with_s_key("Variants");
 
                for variant in &def.variants {
 
                    self.kv(indent3).with_s_key("Variant");
 
                    self.kv(indent4).with_s_key("Name")
 
                        .with_identifier_val(&variant.identifier);
 
                        
 
                    if variant.value.is_empty() {
 
                        self.kv(indent4).with_s_key("Value").with_s_val("None");
 
                    } else {
 
                        self.kv(indent4).with_s_key("Values");
 
                        for embedded in &variant.value {
 
                            self.kv(indent4+1).with_s_key("Value")
 
                                .with_custom_val(|v| write_parser_type(v, heap, embedded));
 
                        }
 
                    }
 
                }
 
            }
 
            Definition::Procedure(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_identifier_val(&def.identifier);
 
                for poly_var_id in &def.poly_vars {
 
                    self.kv(indent3).with_s_key("PolyVar").with_identifier_val(&poly_var_id);
 
                }
 

	
 
                self.kv(indent2).with_s_key("Kind").with_debug_val(&def.kind);
 
                if let Some(parser_type) = &def.return_type {
 
                    self.kv(indent2).with_s_key("ReturnParserType")
 
                        .with_custom_val(|s| write_parser_type(s, heap, parser_type));
 
                }
 

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

	
 
                self.kv(indent2).with_s_key("Body");
 
                self.write_stmt(heap, def.body.upcast(), indent3);
 
                if def.source.is_builtin() {
 
                    self.kv(indent2).with_s_key("Body").with_s_val("Builtin");
 
                } else {
 
                    self.kv(indent2).with_s_key("Body");
 
                    self.write_stmt(heap, def.body.upcast(), indent3);
 
                }
 
            },
 
        }
 
    }
 

	
 
    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");
 
                self.kv(indent2).with_s_key("EndBlockID").with_disp_val(&stmt.end_block.0.index);
 
                self.kv(indent2).with_s_key("ScopeID").with_disp_val(&stmt.scope.index);
 

	
 
                self.kv(indent2).with_s_key("Statements");
 
                for stmt_id in &stmt.statements {
 
                    self.write_stmt(heap, *stmt_id, indent3);
 
                }
 
            },
 
            Statement::EndBlock(stmt) => {
 
                self.kv(indent).with_id(PREFIX_ENDBLOCK_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("EndBlock");
 
                self.kv(indent2).with_s_key("StartBlockID").with_disp_val(&stmt.start_block.0.index);
 
            }
 
            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_variable(heap, stmt.from, indent3);
 
                        self.kv(indent2).with_s_key("To");
 
                        self.write_variable(heap, stmt.to, indent3);
 
                        self.kv(indent2).with_s_key("Next").with_disp_val(&stmt.next.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_variable(heap, stmt.variable, indent3);
 
                        self.kv(indent2).with_s_key("InitialValue");
 
                        self.write_expr(heap, stmt.initial_expr.upcast(), indent3);
 
                        self.kv(indent2).with_s_key("Next").with_disp_val(&stmt.next.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_identifier_val(&stmt.label);
 
                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_disp_val(&stmt.end_if.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_case.body, indent3);
 

	
 
                if let Some(false_body) = stmt.false_case {
 
                    self.kv(indent2).with_s_key("FalseBody");
 
                    self.write_stmt(heap, false_body.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_disp_val(&stmt.next.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_disp_val(&stmt.end_while.0.index);
 
                self.kv(indent2).with_s_key("InSync")
 
                    .with_disp_val(&stmt.in_sync.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_disp_val(&stmt.next.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_identifier_val(stmt.label.as_ref());
 
                self.kv(indent2).with_s_key("Target")
 
                    .with_disp_val(&stmt.target.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_identifier_val(stmt.label.as_ref());
 
                self.kv(indent2).with_s_key("Target")
 
                    .with_disp_val(&stmt.target.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_disp_val(&stmt.end_sync.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_disp_val(&stmt.next.index);
 
            },
 
            Statement::Fork(stmt) => {
 
                self.kv(indent).with_id(PREFIX_FORK_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("Fork");
 
                self.kv(indent2).with_s_key("EndFork").with_disp_val(&stmt.end_fork.0.index);
 
                self.kv(indent2).with_s_key("LeftBody");
 
                self.write_stmt(heap, stmt.left_body, indent3);
 

	
 
                if let Some(right_body_id) = stmt.right_body {
 
                    self.kv(indent2).with_s_key("RightBody");
 
                    self.write_stmt(heap, right_body_id, indent3);
 
                }
 
            },
 
            Statement::EndFork(stmt) => {
 
                self.kv(indent).with_id(PREFIX_END_FORK_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("EndFork");
 
                self.kv(indent2).with_s_key("StartFork").with_disp_val(&stmt.start_fork.0.index);
 
                self.kv(indent2).with_s_key("Next").with_disp_val(&stmt.next.index);
 
            },
 
            Statement::Select(stmt) => {
 
                self.kv(indent).with_id(PREFIX_SELECT_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("Select");
 
                self.kv(indent2).with_s_key("EndSelect").with_disp_val(&stmt.end_select.0.index);
 
                self.kv(indent2).with_s_key("Cases");
 
                let indent3 = indent2 + 1;
 
                let indent4 = indent3 + 1;
 
                for case in &stmt.cases {
 
                    self.kv(indent3).with_s_key("Guard");
 
                    self.write_stmt(heap, case.guard, indent4);
 

	
 
                    self.kv(indent3).with_s_key("Block");
 
                    self.write_stmt(heap, case.body, indent4);
 
                }
 
                self.kv(indent2).with_s_key("Replacement");
 
                self.write_stmt(heap, stmt.next, indent3);
 
            },
 
            Statement::EndSelect(stmt) => {
 
                self.kv(indent).with_id(PREFIX_END_SELECT_STMT_ID, stmt.this.0.index)
 
                    .with_s_key("EndSelect");
 
                self.kv(indent2).with_s_key("StartSelect").with_disp_val(&stmt.start_select.0.index);
 
                self.kv(indent2).with_s_key("Next").with_disp_val(&stmt.next.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("Expressions");
 
                for expr_id in &stmt.expressions {
 
                    self.write_expr(heap, *expr_id, indent3);
 
                }
 
            },
 
            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_identifier_val(&stmt.label);
 
                self.kv(indent2).with_s_key("Target")
 
                    .with_disp_val(&stmt.target.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_disp_val(&stmt.next.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_disp_val(&stmt.next.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;
 

	
 
        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("TypeIndex").with_disp_val(&expr.type_index);
 
                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));
 
            },
 
            Expression::Binding(expr) => {
 
                self.kv(indent).with_id(PREFIX_BINARY_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("BindingExpr");
 
                self.kv(indent2).with_s_key("TypeIndex").with_disp_val(&expr.type_index);
 
                self.kv(indent2).with_s_key("BindToExpression");
 
                self.write_expr(heap, expr.bound_to, indent3);
 
                self.kv(indent2).with_s_key("BindFromExpression");
 
                self.write_expr(heap, expr.bound_from, indent3);
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
            },
 
            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("TypeIndex").with_disp_val(&expr.type_index);
 
                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));
 
            },
 
            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("TypeIndex").with_disp_val(&expr.type_index);
 
                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));
 
            },
 
            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("TypeIndex").with_disp_val(&expr.type_index);
 
                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));
 
            },
 
            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("TypeIndex").with_disp_val(&expr.type_index);
 
                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));
 
            },
 
            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("TypeIndex").with_disp_val(&expr.type_index);
 
                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));
 
            },
 
            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("TypeIndex").with_disp_val(&expr.type_index);
 
                self.kv(indent2).with_s_key("Subject");
 
                self.write_expr(heap, expr.subject, indent3);
 

	
 
                match &expr.kind {
 
                    SelectKind::StructField(field_name) => {
 
                        self.kv(indent2).with_s_key("StructField").with_identifier_val(field_name);
 
                    },
 
                    SelectKind::TupleMember(member_index) => {
 
                        self.kv(indent2).with_s_key("TupleMember").with_disp_val(member_index);
 
                    },
 
                }
 

	
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
            },
 
            Expression::Literal(expr) => {
 
                self.kv(indent).with_id(PREFIX_LITERAL_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("LiteralExpr");
 

	
 
                self.kv(indent2).with_s_key("TypeIndex").with_disp_val(&expr.type_index);
 
                let val = self.kv(indent2).with_s_key("Value");
 
                match &expr.value {
 
                    Literal::Null => { val.with_s_val("null"); },
 
                    Literal::True => { val.with_s_val("true"); },
 
                    Literal::False => { val.with_s_val("false"); },
 
                    Literal::Character(data) => { val.with_disp_val(data); },
 
                    Literal::Bytestring(bytes) => {
 
                        // Bytestrings are ASCII, so just convert back
 
                        let string = String::from_utf8_lossy(bytes.as_slice());
 
                        val.with_disp_val(&string);
 
                    },
 
                    Literal::String(data) => {
 
                        // Stupid hack
 
                        let string = String::from(data.as_str());
 
                        val.with_disp_val(&string);
 
                    },
 
                    Literal::Integer(data) => { val.with_debug_val(data); },
 
                    Literal::Struct(data) => {
 
                        val.with_s_val("Struct");
 
                        let indent4 = indent3 + 1;
 

	
 
                        self.kv(indent3).with_s_key("ParserType")
 
                            .with_custom_val(|t| write_parser_type(t, heap, &data.parser_type));
 
                        self.kv(indent3).with_s_key("Definition").with_disp_val(&data.definition.index);
 

	
 
                        for field in &data.fields {
 
                            self.kv(indent3).with_s_key("Field");
 
                            self.kv(indent4).with_s_key("Name").with_identifier_val(&field.identifier);
 
                            self.kv(indent4).with_s_key("Index").with_disp_val(&field.field_idx);
 
                            self.kv(indent4).with_s_key("ParserType");
 
                            self.write_expr(heap, field.value, indent4 + 1);
 
                        }
 
                    },
 
                    Literal::Enum(data) => {
 
                        val.with_s_val("Enum");
 

	
 
                        self.kv(indent3).with_s_key("ParserType")
 
                            .with_custom_val(|t| write_parser_type(t, heap, &data.parser_type));
 
                        self.kv(indent3).with_s_key("Definition").with_disp_val(&data.definition.index);
 
                        self.kv(indent3).with_s_key("VariantIdx").with_disp_val(&data.variant_idx);
 
                    },
 
                    Literal::Union(data) => {
 
                        val.with_s_val("Union");
 
                        let indent4 = indent3 + 1;
 

	
 
                        self.kv(indent3).with_s_key("ParserType")
 
                            .with_custom_val(|t| write_parser_type(t, heap, &data.parser_type));
 
                        self.kv(indent3).with_s_key("Definition").with_disp_val(&data.definition.index);
 
                        self.kv(indent3).with_s_key("VariantIdx").with_disp_val(&data.variant_idx);
 

	
 
                        for value in &data.values {
 
                            self.kv(indent3).with_s_key("Value");
 
                            self.write_expr(heap, *value, indent4);
 
                        }
 
                    },
 
                    Literal::Array(data) => {
 
                        val.with_s_val("Array");
 
                        let indent4 = indent3 + 1;
 

	
 
                        self.kv(indent3).with_s_key("Elements");
 
                        for expr_id in data {
 
                            self.write_expr(heap, *expr_id, indent4);
 
                        }
 
                    },
 
                    Literal::Tuple(data) => {
 
                        val.with_s_val("Tuple");
 
                        let indent4 = indent3 + 1;
 
                        self.kv(indent3).with_s_key("Elements");
 
                        for expr_id in data {
 
                            self.write_expr(heap, *expr_id, indent4);
 
                        }
 
                    }
 
                }
 

	
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
            },
 
            Expression::Cast(expr) => {
 
                self.kv(indent).with_id(PREFIX_CAST_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("CallExpr");
 
                self.kv(indent2).with_s_key("TypeIndex").with_disp_val(&expr.type_index);
 
                self.kv(indent2).with_s_key("ToType")
 
                    .with_custom_val(|t| write_parser_type(t, heap, &expr.to_type));
 
                self.kv(indent2).with_s_key("Subject");
 
                self.write_expr(heap, expr.subject, indent3);
 
                self.kv(indent2).with_s_key("Parent")
 
                    .with_custom_val(|v| write_expression_parent(v, &expr.parent));
 
            }
 
            Expression::Call(expr) => {
 
                self.kv(indent).with_id(PREFIX_CALL_EXPR_ID, expr.this.0.index)
 
                    .with_s_key("CallExpr");
 

	
 
                self.kv(indent2).with_s_key("TypeIndex").with_disp_val(&expr.type_index);
 
                self.kv(indent2).with_s_key("Method").with_debug_val(&expr.method);
 
                if !expr.procedure.is_invalid() {
 
                    let definition = &heap[expr.procedure];
 
                    self.kv(indent2).with_s_key("Source").with_debug_val(&definition.source);
 
                    self.kv(indent2).with_s_key("Variant").with_debug_val(&definition.kind);
 
                    self.kv(indent2).with_s_key("MethodName").with_identifier_val(&definition.identifier);
 
                    self.kv(indent2).with_s_key("ParserType")
 
                        .with_custom_val(|t| write_parser_type(t, heap, &expr.parser_type));
 
                }
 

	
 
                // 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));
 
            },
 
            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("TypeIndex").with_disp_val(&expr.type_index);
 
                self.kv(indent2).with_s_key("Name").with_identifier_val(&expr.identifier);
 
                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));
 
            }
 
        }
 
    }
 

	
 
    fn write_variable(&mut self, heap: &Heap, variable_id: VariableId, indent: usize) {
 
        let var = &heap[variable_id];
 
        let indent2 = indent + 1;
 

	
 
        self.kv(indent).with_id(PREFIX_VARIABLE_ID, variable_id.index)
 
            .with_s_key("Variable");
 

	
 
        self.kv(indent2).with_s_key("Name").with_identifier_val(&var.identifier);
 
        self.kv(indent2).with_s_key("Kind").with_debug_val(&var.kind);
 
        self.kv(indent2).with_s_key("ParserType")
 
            .with_custom_val(|w| write_parser_type(w, heap, &var.parser_type));
 
        self.kv(indent2).with_s_key("RelativePos").with_disp_val(&var.relative_pos_in_parent);
 
        self.kv(indent2).with_s_key("UniqueScopeID").with_disp_val(&var.unique_id_in_scope);
 
    }
 

	
 
    //--------------------------------------------------------------------------
 
    // 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;
 

	
 
    if t.elements.is_empty() {
 
        target.push_str("no elements in ParserType (can happen due to compiler-inserted AST nodes)");
 
        return;
 
    }
 

	
 
    fn write_element(target: &mut String, heap: &Heap, t: &ParserType, mut element_idx: usize) -> usize {
 
        let element = &t.elements[element_idx];
 
        match &element.variant {
 
            PTV::Void => target.push_str("void"),
 
            PTV::InputOrOutput => {
 
                target.push_str("portlike<");
 
                element_idx = write_element(target, heap, t, element_idx + 1);
 
                target.push('>');
 
            },
 
            PTV::ArrayLike => {
 
                element_idx = write_element(target, heap, t, element_idx + 1);
 
                target.push_str("[???]");
 
            },
 
            PTV::IntegerLike => target.push_str("integerlike"),
 
            PTV::Message => { target.push_str(KW_TYPE_MESSAGE_STR); },
 
            PTV::Bool => { target.push_str(KW_TYPE_BOOL_STR); },
 
            PTV::UInt8 => { target.push_str(KW_TYPE_UINT8_STR); },
 
            PTV::UInt16 => { target.push_str(KW_TYPE_UINT16_STR); },
 
            PTV::UInt32 => { target.push_str(KW_TYPE_UINT32_STR); },
 
            PTV::UInt64 => { target.push_str(KW_TYPE_UINT64_STR); },
 
            PTV::SInt8 => { target.push_str(KW_TYPE_SINT8_STR); },
 
            PTV::SInt16 => { target.push_str(KW_TYPE_SINT16_STR); },
 
            PTV::SInt32 => { target.push_str(KW_TYPE_SINT32_STR); },
 
            PTV::SInt64 => { target.push_str(KW_TYPE_SINT64_STR); },
 
            PTV::Character => { target.push_str(KW_TYPE_CHAR_STR); },
 
            PTV::String => { target.push_str(KW_TYPE_STRING_STR); },
 
            PTV::IntegerLiteral => { target.push_str("int_literal"); },
 
            PTV::Inferred => { target.push_str(KW_TYPE_INFERRED_STR); },
 
            PTV::Array => {
 
                element_idx = write_element(target, heap, t, element_idx + 1);
 
                target.push_str("[]");
 
            },
src/protocol/eval/executor.rs
Show inline comments
 

	
 
use std::collections::VecDeque;
 

	
 
use super::value::*;
 
use super::store::*;
 
use super::error::*;
 
use crate::protocol::*;
 
use crate::protocol::ast::*;
 
use crate::protocol::type_table::*;
 

	
 
macro_rules! debug_enabled { () => { false }; }
 
macro_rules! debug_log {
 
    ($format:literal) => {
 
        enabled_debug_print!(false, "exec", $format);
 
    };
 
    ($format:literal, $($args:expr),*) => {
 
        enabled_debug_print!(false, "exec", $format, $($args),*);
 
    };
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub(crate) enum ExprInstruction {
 
    EvalExpr(ExpressionId),
 
    PushValToFront,
 
}
 

	
 
#[derive(Debug, Clone)]
 
pub(crate) struct Frame {
 
    pub(crate) definition: ProcedureDefinitionId,
 
    pub(crate) monomorph_index: usize,
 
    pub(crate) position: StatementId,
 
    pub(crate) expr_stack: VecDeque<ExprInstruction>, // hack for expression evaluation, evaluated by popping from back
 
    pub(crate) expr_values: VecDeque<Value>, // hack for expression results, evaluated by popping from front/back
 
    pub(crate) max_stack_size: u32,
 
}
 

	
 
impl Frame {
 
    /// Creates a new execution frame. Does not modify the stack in any way.
 
    pub fn new(heap: &Heap, definition_id: ProcedureDefinitionId, _monomorph_type_id: TypeId, monomorph_index: u32) -> Self {
 
        let definition = &heap[definition_id];
 
        let outer_scope_id = definition.scope;
 
        let first_statement_id = definition.body;
 

	
 
        // Another not-so-pretty thing that has to be replaced somewhere in the
 
        // future...
 
        fn determine_max_stack_size(heap: &Heap, scope_id: ScopeId, max_size: &mut u32) {
 
            let scope = &heap[scope_id];
 

	
 
            // Check current block
 
            let cur_size = scope.next_unique_id_in_scope as u32;
 
            if cur_size > *max_size { *max_size = cur_size; }
 

	
 
            // And child blocks
 
            for child_scope in &scope.nested {
 
                determine_max_stack_size(heap, *child_scope, max_size);
 
            }
 
        }
 

	
 
        let mut max_stack_size = 0;
 
        determine_max_stack_size(heap, outer_scope_id, &mut max_stack_size);
 

	
 
        Frame{
 
            definition: definition_id,
 
            monomorph_index: monomorph_index as usize,
 
            position: first_statement_id.upcast(),
 
            expr_stack: VecDeque::with_capacity(128),
 
            expr_values: VecDeque::with_capacity(128),
 
            max_stack_size,
 
        }
 
    }
 

	
 
    /// Prepares a single expression for execution. This involves walking the
 
    /// expression tree and putting them in the `expr_stack` such that
 
    /// continuously popping from its back will evaluate the expression. The
 
    /// results of each expression will be stored by pushing onto `expr_values`.
 
    pub fn prepare_single_expression(&mut self, heap: &Heap, expr_id: ExpressionId) {
 
        debug_assert!(self.expr_stack.is_empty());
 
        self.expr_values.clear(); // May not be empty if last expression result(s) were discarded
 

	
 
        self.serialize_expression(heap, expr_id);
 
    }
 

	
 
    /// Prepares multiple expressions for execution (i.e. evaluating all
 
    /// function arguments or all elements of an array/union literal). Per
 
    /// expression this works the same as `prepare_single_expression`. However
 
    /// after each expression is evaluated we insert a `PushValToFront`
 
    /// instruction
 
    pub fn prepare_multiple_expressions(&mut self, heap: &Heap, expr_ids: &[ExpressionId]) {
 
        debug_assert!(self.expr_stack.is_empty());
 
        self.expr_values.clear();
 

	
 
        for expr_id in expr_ids {
 
            self.expr_stack.push_back(ExprInstruction::PushValToFront);
 
            self.serialize_expression(heap, *expr_id);
 
        }
 
    }
 

	
 
    /// Performs depth-first serialization of expression tree. Let's not care
 
    /// about performance for a temporary runtime implementation
 
    fn serialize_expression(&mut self, heap: &Heap, id: ExpressionId) {
 
        self.expr_stack.push_back(ExprInstruction::EvalExpr(id));
 

	
 
        match &heap[id] {
 
            Expression::Assignment(expr) => {
 
                self.serialize_expression(heap, expr.left);
 
                self.serialize_expression(heap, expr.right);
 
            },
 
            Expression::Binding(expr) => {
 
                self.serialize_expression(heap, expr.bound_to);
 
                self.serialize_expression(heap, expr.bound_from);
 
            },
 
            Expression::Conditional(expr) => {
 
                self.serialize_expression(heap, expr.test);
 
            },
 
            Expression::Binary(expr) => {
 
                self.serialize_expression(heap, expr.left);
 
                self.serialize_expression(heap, expr.right);
 
            },
 
            Expression::Unary(expr) => {
 
                self.serialize_expression(heap, expr.expression);
 
            },
 
            Expression::Indexing(expr) => {
 
                self.serialize_expression(heap, expr.index);
 
                self.serialize_expression(heap, expr.subject);
 
            },
 
            Expression::Slicing(expr) => {
 
                self.serialize_expression(heap, expr.from_index);
 
                self.serialize_expression(heap, expr.to_index);
 
                self.serialize_expression(heap, expr.subject);
 
            },
 
            Expression::Select(expr) => {
 
                self.serialize_expression(heap, expr.subject);
 
            },
 
            Expression::Literal(expr) => {
 
                // Here we only care about literals that have subexpressions
 
                match &expr.value {
 
                    Literal::Null | Literal::True | Literal::False |
 
                    Literal::Character(_) | Literal::String(_) |
 
                    Literal::Character(_) | Literal::Bytestring(_) | Literal::String(_) |
 
                    Literal::Integer(_) | Literal::Enum(_) => {
 
                        // No subexpressions
 
                    },
 
                    Literal::Struct(literal) => {
 
                        // Note: fields expressions are evaluated in programmer-
 
                        // specified order. But struct construction expects them
 
                        // in type-defined order. I might want to come back to
 
                        // this.
 
                        let mut _num_pushed = 0;
 
                        for want_field_idx in 0..literal.fields.len() {
 
                            for field in &literal.fields {
 
                                if field.field_idx == want_field_idx {
 
                                    _num_pushed += 1;
 
                                    self.expr_stack.push_back(ExprInstruction::PushValToFront);
 
                                    self.serialize_expression(heap, field.value);
 
                                }
 
                            }
 
                        }
 
                        debug_assert_eq!(_num_pushed, literal.fields.len())
 
                    },
 
                    Literal::Union(literal) => {
 
                        for value_expr_id in &literal.values {
 
                            self.expr_stack.push_back(ExprInstruction::PushValToFront);
 
                            self.serialize_expression(heap, *value_expr_id);
 
                        }
 
                    },
 
                    Literal::Array(value_expr_ids) => {
 
                        for value_expr_id in value_expr_ids {
 
                            self.expr_stack.push_back(ExprInstruction::PushValToFront);
 
                            self.serialize_expression(heap, *value_expr_id);
 
                        }
 
                    },
 
                    Literal::Tuple(value_expr_ids) => {
 
                        for value_expr_id in value_expr_ids {
 
                            self.expr_stack.push_back(ExprInstruction::PushValToFront);
 
                            self.serialize_expression(heap, *value_expr_id);
 
                        }
 
                    }
 
                }
 
            },
 
            Expression::Cast(expr) => {
 
                self.serialize_expression(heap, expr.subject);
 
            }
 
            Expression::Call(expr) => {
 
                for arg_expr_id in &expr.arguments {
 
                    self.expr_stack.push_back(ExprInstruction::PushValToFront);
 
                    self.serialize_expression(heap, *arg_expr_id);
 
                }
 
            },
 
            Expression::Variable(_expr) => {
 
                // No subexpressions
 
            }
 
        }
 
    }
 
}
 

	
 
pub type EvalResult = Result<EvalContinuation, EvalError>;
 

	
 
#[derive(Debug)]
 
pub enum EvalContinuation {
 
    // Returned in both sync and non-sync modes
 
    Stepping,
 
    // Returned only in sync mode
 
    BranchInconsistent,
 
    SyncBlockEnd,
 
    NewFork,
 
    BlockFires(PortId),
 
    BlockGet(PortId),
 
    Put(PortId, ValueGroup),
 
    SelectStart(u32, u32), // (num_cases, num_ports_total)
 
    SelectRegisterPort(u32, u32, PortId), // (case_index, port_index_in_case, port_id)
 
    SelectWait, // wait until select can continue
 
    // Returned only in non-sync mode
 
    ComponentTerminated,
 
    SyncBlockStart,
 
    NewComponent(ProcedureDefinitionId, TypeId, ValueGroup),
 
    NewChannel,
 
}
 

	
 
// Note: cloning is fine, methinks. cloning all values and the heap regions then
 
// we end up with valid "pointers" to heap regions.
 
#[derive(Debug, Clone)]
 
pub struct Prompt {
 
    pub(crate) frames: Vec<Frame>,
 
    pub(crate) store: Store,
 
}
 

	
 
impl Prompt {
 
    pub fn new(types: &TypeTable, heap: &Heap, def: ProcedureDefinitionId, type_id: TypeId, args: ValueGroup) -> Self {
 
        let mut prompt = Self{
 
            frames: Vec::new(),
 
            store: Store::new(),
 
        };
 

	
 
        // Maybe do typechecking in the future?
 
        let monomorph_index = types.get_monomorph(type_id).variant.as_procedure().monomorph_index;
 
        let new_frame = Frame::new(heap, def, type_id, monomorph_index);
 
        let max_stack_size = new_frame.max_stack_size;
 
        prompt.frames.push(new_frame);
 
        args.into_store(&mut prompt.store);
 
        prompt.store.reserve_stack(max_stack_size);
 

	
 
        prompt
 
    }
 

	
 
    /// Big 'ol function right here. Didn't want to break it up unnecessarily.
 
    /// It consists of, in sequence: executing any expressions that should be
 
    /// executed before the next statement can be evaluated, then a section that
 
    /// performs debug printing, and finally a section that takes the next
 
    /// statement and executes it. If the statement requires any expressions to
 
    /// be evaluated, then they will be added such that the next time `step` is
 
    /// called, all of these expressions are indeed evaluated.
 
    pub(crate) fn step(&mut self, types: &TypeTable, heap: &Heap, modules: &[Module], ctx: &mut impl RunContext) -> EvalResult {
 
        // Helper function to transfer multiple values from the expression value
 
        // array into a heap region (e.g. constructing arrays or structs).
 
        fn transfer_expression_values_front_into_heap(cur_frame: &mut Frame, store: &mut Store, num_values: usize) -> HeapPos {
 
            let heap_pos = store.alloc_heap();
 

	
 
            // Do the transformation first (because Rust...)
 
            for val_idx in 0..num_values {
 
                cur_frame.expr_values[val_idx] = store.read_take_ownership(cur_frame.expr_values[val_idx].clone());
 
            }
 

	
 
            // And now transfer to the heap region
 
            let values = &mut store.heap_regions[heap_pos as usize].values;
 
            debug_assert!(values.is_empty());
 
            values.reserve(num_values);
 
            for _ in 0..num_values {
 
                values.push(cur_frame.expr_values.pop_front().unwrap());
 
            }
 

	
 
            heap_pos
 
        }
 

	
 
        // Helper function to make sure that an index into an aray is valid.
 
        fn array_inclusive_index_is_invalid(store: &Store, array_heap_pos: u32, idx: i64) -> bool {
 
            let array_len = store.heap_regions[array_heap_pos as usize].values.len();
 
            return idx < 0 || idx >= array_len as i64;
 
        }
 

	
 
        fn array_exclusive_index_is_invalid(store: &Store, array_heap_pos: u32, idx: i64) -> bool {
 
            let array_len = store.heap_regions[array_heap_pos as usize].values.len();
 
            return idx < 0 || idx > array_len as i64;
 
        }
 

	
 
        fn construct_array_error(prompt: &Prompt, modules: &[Module], heap: &Heap, expr_id: ExpressionId, heap_pos: u32, idx: i64) -> EvalError {
 
            let array_len = prompt.store.heap_regions[heap_pos as usize].values.len();
 
            return EvalError::new_error_at_expr(
 
                prompt, modules, heap, expr_id,
 
                format!("index {} is out of bounds: array length is {}", idx, array_len)
 
            )
 
        }
 

	
 
        // Checking if we're at the end of execution
 
        let cur_frame = self.frames.last_mut().unwrap();
 
        if cur_frame.position.is_invalid() {
 
            if heap[cur_frame.definition].kind == ProcedureKind::Function {
 
                todo!("End of function without return, return an evaluation error");
 
            }
 
            return Ok(EvalContinuation::ComponentTerminated);
 
        }
 

	
 
        debug_log!("Taking step in '{}'", heap[cur_frame.definition].identifier.value.as_str());
 

	
 
        // Execute all pending expressions
 
        while !cur_frame.expr_stack.is_empty() {
 
            let next = cur_frame.expr_stack.pop_back().unwrap();
 
            debug_log!("Expr stack: {:?}", next);
 
            match next {
 
                ExprInstruction::PushValToFront => {
 
                    cur_frame.expr_values.rotate_right(1);
 
                },
 
                ExprInstruction::EvalExpr(expr_id) => {
 
                    let expr = &heap[expr_id];
 
                    match expr {
 
                        Expression::Assignment(expr) => {
 
                            let to = cur_frame.expr_values.pop_back().unwrap().as_ref();
 
                            let rhs = cur_frame.expr_values.pop_back().unwrap();
 

	
 
                            // Note: although not pretty, the assignment operator takes ownership
 
                            // of the right-hand side value when possible. So we do not drop the
 
                            // rhs's optionally owned heap data.
 
                            let rhs = self.store.read_take_ownership(rhs);
 
                            apply_assignment_operator(&mut self.store, to, expr.operation, rhs);
 
                        },
 
                        Expression::Binding(_expr) => {
 
                            let bind_to = cur_frame.expr_values.pop_back().unwrap();
 
                            let bind_from = cur_frame.expr_values.pop_back().unwrap();
 
                            let bind_to_heap_pos = bind_to.get_heap_pos();
 
                            let bind_from_heap_pos = bind_from.get_heap_pos();
 

	
 
                            let result = apply_binding_operator(&mut self.store, bind_to, bind_from);
 
                            self.store.drop_value(bind_to_heap_pos);
 
                            self.store.drop_value(bind_from_heap_pos);
 
                            cur_frame.expr_values.push_back(Value::Bool(result));
 
                        },
 
                        Expression::Conditional(expr) => {
 
                            // Evaluate testing expression, then extend the
 
                            // expression stack with the appropriate expression
 
                            let test_result = cur_frame.expr_values.pop_back().unwrap().as_bool();
 
                            if test_result {
 
                                cur_frame.serialize_expression(heap, expr.true_expression);
 
                            } else {
 
                                cur_frame.serialize_expression(heap, expr.false_expression);
 
                            }
 
                        },
 
                        Expression::Binary(expr) => {
 
                            let lhs = cur_frame.expr_values.pop_back().unwrap();
 
                            let rhs = cur_frame.expr_values.pop_back().unwrap();
 
                            let result = apply_binary_operator(&mut self.store, &lhs, expr.operation, &rhs);
 
                            cur_frame.expr_values.push_back(result);
 
                            self.store.drop_value(lhs.get_heap_pos());
 
                            self.store.drop_value(rhs.get_heap_pos());
 
                        },
 
                        Expression::Unary(expr) => {
 
                            let val = cur_frame.expr_values.pop_back().unwrap();
 
                            let result = apply_unary_operator(&mut self.store, expr.operation, &val);
 
                            cur_frame.expr_values.push_back(result);
 
                            self.store.drop_value(val.get_heap_pos());
 
                        },
 
                        Expression::Indexing(_expr) => {
 
                            // Evaluate index. Never heap allocated so we do
 
                            // not have to drop it.
 
                            let index = cur_frame.expr_values.pop_back().unwrap();
 
                            let index = self.store.maybe_read_ref(&index);
 

	
 
                            debug_assert!(index.is_integer());
 
                            let index = if index.is_signed_integer() {
 
                                index.as_signed_integer() as i64
 
                            } else {
 
                                index.as_unsigned_integer() as i64
 
                            };
 

	
 
                            let subject = cur_frame.expr_values.pop_back().unwrap();
 

	
 
                            let (deallocate_heap_pos, value_to_push) = match subject {
 
                                Value::Ref(value_ref) => {
 
                                    // Our expression stack value is a reference to something that
 
                                    // exists in the normal stack/heap. We don't want to deallocate
 
                                    // this thing. Rather we want to return a reference to it.
 
                                    let subject = self.store.read_ref(value_ref);
 
                                    let subject_heap_pos = match subject {
 
                                        Value::String(v) => *v,
 
                                        Value::Array(v) => *v,
 
                                        Value::Message(v) => *v,
 
                                        _ => unreachable!(),
 
                                    };
 

	
 
                                    if array_inclusive_index_is_invalid(&self.store, subject_heap_pos, index) {
 
                                        return Err(construct_array_error(self, modules, heap, expr_id, subject_heap_pos, index));
 
                                    }
 

	
 
                                    (None, Value::Ref(ValueId::Heap(subject_heap_pos, index as u32)))
 
                                },
 
                                _ => {
 
                                    // Our value lives on the expression stack, hence we need to
 
                                    // clone whatever we're referring to. Then drop the subject.
 
                                    let subject_heap_pos = match &subject {
 
                                        Value::String(v) => *v,
 
                                        Value::Array(v) => *v,
 
                                        Value::Message(v) => *v,
 
                                        _ => unreachable!(),
 
                                    };
 

	
 
                                    if array_inclusive_index_is_invalid(&self.store, subject_heap_pos, index) {
 
                                        return Err(construct_array_error(self, modules, heap, expr_id, subject_heap_pos, index));
 
                                    }
 

	
 
                                    let subject_indexed = Value::Ref(ValueId::Heap(subject_heap_pos, index as u32));
 
                                    (Some(subject_heap_pos), self.store.clone_value(subject_indexed))
 
                                },
 
                            };
 

	
 
                            cur_frame.expr_values.push_back(value_to_push);
 
                            self.store.drop_value(deallocate_heap_pos);
 
                        },
 
                        Expression::Slicing(expr) => {
 
                            // Evaluate indices
 
                            let from_index = cur_frame.expr_values.pop_back().unwrap();
 
                            let from_index = self.store.maybe_read_ref(&from_index);
 
                            let to_index = cur_frame.expr_values.pop_back().unwrap();
 
                            let to_index = self.store.maybe_read_ref(&to_index);
 

	
 
                            debug_assert!(from_index.is_integer() && to_index.is_integer());
 
                            let from_index = if from_index.is_signed_integer() {
 
                                from_index.as_signed_integer()
 
                            } else {
 
                                from_index.as_unsigned_integer() as i64
 
                            };
 
                            let to_index = if to_index.is_signed_integer() {
 
                                to_index.as_signed_integer()
 
                            } else {
 
                                to_index.as_unsigned_integer() as i64
 
                            };
 

	
 
                            // Dereference subject if needed
 
                            let subject = cur_frame.expr_values.pop_back().unwrap();
 
                            let deref_subject = self.store.maybe_read_ref(&subject);
 

	
 
                            // Slicing needs to produce a copy anyway (with the
 
                            // current evaluator implementation)
 
                            enum ValueKind{ Array, String, Message }
 
                            let (value_kind, array_heap_pos) = match deref_subject {
 
                                Value::Array(v) => (ValueKind::Array, *v),
 
                                Value::String(v) => (ValueKind::String, *v),
 
                                Value::Message(v) => (ValueKind::Message, *v),
 
                                _ => unreachable!()
 
                            };
 

	
 
                            if array_inclusive_index_is_invalid(&self.store, array_heap_pos, from_index) {
 
                                return Err(construct_array_error(self, modules, heap, expr.from_index, array_heap_pos, from_index));
 
                            }
 
                            if array_exclusive_index_is_invalid(&self.store, array_heap_pos, to_index) {
 
                                return Err(construct_array_error(self, modules, heap, expr.to_index, array_heap_pos, to_index));
 
                            }
 

	
 
                            // Again: would love to push directly, but rust...
 
                            let new_heap_pos = self.store.alloc_heap();
 
                            debug_assert!(self.store.heap_regions[new_heap_pos as usize].values.is_empty());
 
                            if to_index > from_index {
 
                                let from_index = from_index as usize;
 
                                let to_index = to_index as usize;
 
                                let mut values = Vec::with_capacity(to_index - from_index);
 
                                for idx in from_index..to_index {
 
                                    let value = self.store.heap_regions[array_heap_pos as usize].values[idx].clone();
 
                                    values.push(self.store.clone_value(value));
 
                                }
 

	
 
                                self.store.heap_regions[new_heap_pos as usize].values = values;
 

	
 
                            } // else: empty range
 

	
 
                            cur_frame.expr_values.push_back(match value_kind {
 
                                ValueKind::Array => Value::Array(new_heap_pos),
 
                                ValueKind::String => Value::String(new_heap_pos),
 
                                ValueKind::Message => Value::Message(new_heap_pos),
 
                            });
 

	
 
                            // Dropping the original subject, because we don't
 
                            // want to drop something on the stack
 
                            self.store.drop_value(subject.get_heap_pos());
 
                        },
 
                        Expression::Select(expr) => {
 
                            let subject= cur_frame.expr_values.pop_back().unwrap();
 
                            let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
 
                            let field_idx = mono_data.expr_info[expr.type_index as usize].variant.as_select() as u32;
 

	
 
                            // Note: same as above: clone if value lives on expr stack, simply
 
                            // refer to it if it already lives on the stack/heap.
 
                            let (deallocate_heap_pos, value_to_push) = match subject {
 
                                Value::Ref(value_ref) => {
 
                                    let subject = self.store.read_ref(value_ref);
 
                                    let subject_heap_pos = match expr.kind {
 
                                        SelectKind::StructField(_) => subject.as_struct(),
 
                                        SelectKind::TupleMember(_) => subject.as_tuple(),
 
                                    };
 

	
 
                                    (None, Value::Ref(ValueId::Heap(subject_heap_pos, field_idx)))
 
                                },
 
                                _ => {
 
                                    let subject_heap_pos = match expr.kind {
 
                                        SelectKind::StructField(_) => subject.as_struct(),
 
                                        SelectKind::TupleMember(_) => subject.as_tuple(),
 
                                    };
 
                                    let subject_indexed = Value::Ref(ValueId::Heap(subject_heap_pos, field_idx));
 
                                    (Some(subject_heap_pos), self.store.clone_value(subject_indexed))
 
                                },
 
                            };
 

	
 
                            cur_frame.expr_values.push_back(value_to_push);
 
                            self.store.drop_value(deallocate_heap_pos);
 
                        },
 
                        Expression::Literal(expr) => {
 
                            let value = match &expr.value {
 
                                Literal::Null => Value::Null,
 
                                Literal::True => Value::Bool(true),
 
                                Literal::False => Value::Bool(false),
 
                                Literal::Character(lit_value) => Value::Char(*lit_value),
 
                                Literal::Bytestring(lit_value) => {
 
                                    let heap_pos = self.store.alloc_heap();
 
                                    let values = &mut self.store.heap_regions[heap_pos as usize].values;
 
                                    debug_assert!(values.is_empty());
 
                                    values.reserve(lit_value.len());
 
                                    for byte in lit_value {
 
                                        values.push(Value::UInt8(*byte));
 
                                    }
 
                                    Value::Array(heap_pos)
 
                                }
 
                                Literal::String(lit_value) => {
 
                                    let heap_pos = self.store.alloc_heap();
 
                                    let values = &mut self.store.heap_regions[heap_pos as usize].values;
 
                                    let value = lit_value.as_str();
 
                                    debug_assert!(values.is_empty());
 
                                    values.reserve(value.len());
 
                                    for character in value.as_bytes() {
 
                                        debug_assert!(character.is_ascii());
 
                                        values.push(Value::Char(*character as char));
 
                                    }
 
                                    Value::String(heap_pos)
 
                                }
 
                                Literal::Integer(lit_value) => {
 
                                    use ConcreteTypePart as CTP;
 
                                    let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
 
                                    let type_id = mono_data.expr_info[expr.type_index as usize].type_id;
 
                                    let concrete_type = &types.get_monomorph(type_id).concrete_type;
 

	
 
                                    debug_assert_eq!(concrete_type.parts.len(), 1);
 
                                    match concrete_type.parts[0] {
 
                                        CTP::UInt8  => Value::UInt8(lit_value.unsigned_value as u8),
 
                                        CTP::UInt16 => Value::UInt16(lit_value.unsigned_value as u16),
 
                                        CTP::UInt32 => Value::UInt32(lit_value.unsigned_value as u32),
 
                                        CTP::UInt64 => Value::UInt64(lit_value.unsigned_value as u64),
 
                                        CTP::SInt8  => Value::SInt8(lit_value.unsigned_value as i8),
 
                                        CTP::SInt16 => Value::SInt16(lit_value.unsigned_value as i16),
 
                                        CTP::SInt32 => Value::SInt32(lit_value.unsigned_value as i32),
 
                                        CTP::SInt64 => Value::SInt64(lit_value.unsigned_value as i64),
 
                                        _ => unreachable!("got concrete type {:?} for integer literal at expr {:?}", concrete_type, expr_id),
 
                                    }
 
                                }
 
                                Literal::Struct(lit_value) => {
 
                                    let heap_pos = transfer_expression_values_front_into_heap(
 
                                        cur_frame, &mut self.store, lit_value.fields.len()
 
                                    );
 
                                    Value::Struct(heap_pos)
 
                                }
 
                                Literal::Enum(lit_value) => {
 
                                    Value::Enum(lit_value.variant_idx as i64)
 
                                }
 
                                Literal::Union(lit_value) => {
 
                                    let heap_pos = transfer_expression_values_front_into_heap(
 
                                        cur_frame, &mut self.store, lit_value.values.len()
 
                                    );
 
                                    Value::Union(lit_value.variant_idx as i64, heap_pos)
 
                                }
 
                                Literal::Array(lit_value) => {
 
                                    let heap_pos = transfer_expression_values_front_into_heap(
 
                                        cur_frame, &mut self.store, lit_value.len()
 
                                    );
 
                                    Value::Array(heap_pos)
 
                                }
 
                                Literal::Tuple(lit_value) => {
 
                                    let heap_pos = transfer_expression_values_front_into_heap(
 
                                        cur_frame, &mut self.store, lit_value.len()
 
                                    );
 
                                    Value::Tuple(heap_pos)
 
                                }
 
                            };
 

	
 
                            cur_frame.expr_values.push_back(value);
 
                        },
 
                        Expression::Cast(expr) => {
 
                            let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
 
                            let type_id = mono_data.expr_info[expr.type_index as usize].type_id;
 
                            let concrete_type = &types.get_monomorph(type_id).concrete_type;
 

	
 
                            // Typechecking reduced this to two cases: either we
 
                            // have casting noop (same types), or we're casting
 
                            // between integer/bool/char types.
 
                            let subject = cur_frame.expr_values.pop_back().unwrap();
 
                            match apply_casting(&mut self.store, concrete_type, &subject) {
 
                                Ok(value) => cur_frame.expr_values.push_back(value),
 
                                Err(msg) => {
 
                                    return Err(EvalError::new_error_at_expr(self, modules, heap, expr.this.upcast(), msg));
 
                                }
 
                            }
 

	
 
                            self.store.drop_value(subject.get_heap_pos());
 
                        }
 
                        Expression::Call(expr) => {
 
                            // If we're dealing with a builtin we don't do any
 
                            // fancy shenanigans at all, just push the result.
 
                            match expr.method {
 
                                Method::Get => {
 
                                    let value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let value = self.store.maybe_read_ref(&value).clone();
 

	
 
                                    let port_id = if let Value::Input(port_id) = value {
 
                                        port_id
 
                                    } else {
 
                                        unreachable!("executor calling 'get' on value {:?}", value)
 
                                    };
 

	
 
                                    match ctx.performed_get(port_id) {
 
                                        Some(result) => {
 
                                            // We have the result. Merge the `ValueGroup` with the
 
                                            // stack/heap storage.
 
                                            debug_assert_eq!(result.values.len(), 1);
 
                                            result.into_stack(&mut cur_frame.expr_values, &mut self.store);
 
                                        },
 
                                        None => {
 
                                            // Don't have the result yet, prepare the expression to
 
                                            // get run again after we've received a message.
 
                                            cur_frame.expr_values.push_front(value.clone());
 
                                            cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr_id));
 
                                            return Ok(EvalContinuation::BlockGet(port_id));
 
                                        }
 
                                    }
 
                                },
 
                                Method::Put => {
 
                                    let port_value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let deref_port_value = self.store.maybe_read_ref(&port_value).clone();
 

	
 
                                    let port_id = if let Value::Output(port_id) = deref_port_value {
 
                                        port_id
 
                                    } else {
 
                                        unreachable!("executor calling 'put' on value {:?}", deref_port_value)
 
                                    };
 

	
 
                                    let msg_value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let deref_msg_value = self.store.maybe_read_ref(&msg_value).clone();
 

	
 
                                    if ctx.performed_put(port_id) {
 
                                        // We're fine, deallocate in case the expression value stack
 
                                        // held an owned value
 
                                        self.store.drop_value(msg_value.get_heap_pos());
 
                                    } else {
 
                                        // Prepare to execute again
 
                                        cur_frame.expr_values.push_front(msg_value);
 
                                        cur_frame.expr_values.push_front(port_value);
 
                                        cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr_id));
 
                                        let value_group = ValueGroup::from_store(&self.store, &[deref_msg_value]);
 
                                        return Ok(EvalContinuation::Put(port_id, value_group));
 
                                    }
 
                                },
 
                                Method::Fires => {
 
                                    let port_value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let port_value_deref = self.store.maybe_read_ref(&port_value).clone();
 
                                    let port_id = port_value_deref.as_port_id();
 

	
 
                                    match ctx.fires(port_id) {
 
                                        None => {
 
                                            cur_frame.expr_values.push_front(port_value);
 
                                            cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr_id));
 
                                            return Ok(EvalContinuation::BlockFires(port_id));
 
                                        },
 
                                        Some(value) => {
 
                                            cur_frame.expr_values.push_back(value);
 
                                        }
 
                                    }
 
                                },
 
                                Method::Create => {
 
                                    let length_value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let length_value = self.store.maybe_read_ref(&length_value);
 
                                    let length = if length_value.is_signed_integer() {
 
                                        let length_value = length_value.as_signed_integer();
 
                                        if length_value < 0 {
 
                                            return Err(EvalError::new_error_at_expr(
 
                                                self, modules, heap, expr_id,
 
                                                format!("got length '{}', can only create a message with a non-negative length", length_value)
 
                                            ));
 
                                        }
 

	
 
                                        length_value as u64
 
                                    } else {
 
                                        debug_assert!(length_value.is_unsigned_integer());
 
                                        length_value.as_unsigned_integer()
 
                                    };
 

	
 
                                    let heap_pos = self.store.alloc_heap();
 
                                    let values = &mut self.store.heap_regions[heap_pos as usize].values;
 
                                    debug_assert!(values.is_empty());
 
                                    values.resize(length as usize, Value::UInt8(0));
 
                                    cur_frame.expr_values.push_back(Value::Message(heap_pos));
 
                                },
 
                                Method::Length => {
 
                                    let value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let value_heap_pos = value.get_heap_pos();
 
                                    let value = self.store.maybe_read_ref(&value);
 

	
 
                                    let heap_pos = match value {
 
                                        Value::Array(pos) => *pos,
 
                                        Value::String(pos) => *pos,
 
                                        _ => unreachable!("length(...) on {:?}", value),
 
                                    };
 

	
 
                                    let len = self.store.heap_regions[heap_pos as usize].values.len();
 

	
 
                                    // TODO: @PtrInt
 
                                    cur_frame.expr_values.push_back(Value::UInt32(len as u32));
 
                                    self.store.drop_value(value_heap_pos);
 
                                },
 
                                Method::Assert => {
 
                                    let value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let value = self.store.maybe_read_ref(&value).clone();
 
                                    if !value.as_bool() {
 
                                        return Ok(EvalContinuation::BranchInconsistent)
 
                                    }
 
                                },
 
                                Method::Print => {
 
                                    // Convert the runtime-variant of a string
 
                                    // into an actual string.
 
                                    let value = cur_frame.expr_values.pop_front().unwrap();
 
                                    let mut is_literal_string = value.get_heap_pos().is_some();
 
                                    let value = self.store.maybe_read_ref(&value);
 
                                    let value_heap_pos = value.as_string();
 
                                    let elements = &self.store.heap_regions[value_heap_pos as usize].values;
 

	
 
                                    let mut message = String::with_capacity(elements.len());
 
                                    for element in elements {
 
                                        message.push(element.as_char());
 
                                    }
 

	
 
                                    // Drop the heap-allocated value from the
 
                                    // store
 
                                    self.store.drop_heap_pos(value_heap_pos);
 
                                    if is_literal_string {
 
                                        self.store.drop_heap_pos(value_heap_pos);
 
                                    }
 

	
 
                                    println!("{}", message);
 
                                },
 
                                Method::SelectStart => {
 
                                    let num_cases = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_uint32();
 
                                    let num_ports = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_uint32();
 

	
 
                                    return Ok(EvalContinuation::SelectStart(num_cases, num_ports));
 
                                },
 
                                Method::SelectRegisterCasePort => {
 
                                    let case_index = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_uint32();
 
                                    let port_index = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_uint32();
 
                                    let port_value = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_port_id();
 

	
 
                                    return Ok(EvalContinuation::SelectRegisterPort(case_index, port_index, port_value));
 
                                },
 
                                Method::SelectWait => {
 
                                    match ctx.performed_select_wait() {
 
                                        Some(select_index) => {
 
                                            cur_frame.expr_values.push_back(Value::UInt32(select_index));
 
                                        },
 
                                        None => {
 
                                            cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr.this.upcast()));
 
                                            return Ok(EvalContinuation::SelectWait)
 
                                        },
 
                                    }
 
                                },
 
                                Method::ComponentRandomU32 | Method::ComponentTcpClient => {
 
                                    debug_assert_eq!(heap[expr.procedure].parameters.len(), cur_frame.expr_values.len());
 
                                    debug_assert_eq!(heap[cur_frame.position].as_new().expression, expr.this);
 
                                },
 
                                Method::UserComponent => {
 
                                    // This is actually handled by the evaluation
 
                                    // of the statement.
 
                                    debug_assert_eq!(heap[expr.procedure].parameters.len(), cur_frame.expr_values.len());
 
                                    debug_assert_eq!(heap[cur_frame.position].as_new().expression, expr.this);
 
                                },
 
                                Method::UserFunction => {
 
                                    // Push a new frame. Note that all expressions have
 
                                    // been pushed to the front, so they're in the order
 
                                    // of the definition.
 
                                    let num_args = expr.arguments.len();
 

	
 
                                    // Determine stack boundaries
 
                                    let cur_stack_boundary = self.store.cur_stack_boundary;
 
                                    let new_stack_boundary = self.store.stack.len();
 

	
 
                                    // Push new boundary and function arguments for new frame
 
                                    self.store.stack.push(Value::PrevStackBoundary(cur_stack_boundary as isize));
 
                                    for _ in 0..num_args {
 
                                        let argument = self.store.read_take_ownership(cur_frame.expr_values.pop_front().unwrap());
 
                                        self.store.stack.push(argument);
 
                                    }
 

	
 
                                    // Determine the monomorph index of the function we're calling
 
                                    let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
 
                                    let (type_id, monomorph_index) = mono_data.expr_info[expr.type_index as usize].variant.as_procedure();
 

	
 
                                    // Push the new frame and reserve its stack size
 
                                    let new_frame = Frame::new(heap, expr.procedure, type_id, monomorph_index);
 
                                    let new_stack_size = new_frame.max_stack_size;
 
                                    self.frames.push(new_frame);
 
                                    self.store.cur_stack_boundary = new_stack_boundary;
 
                                    self.store.reserve_stack(new_stack_size);
 

	
 
                                    // To simplify the logic a little bit we will now
 
                                    // return and ask our caller to call us again
 
                                    return Ok(EvalContinuation::Stepping);
 
                                }
 
                            }
 
                        },
 
                        Expression::Variable(expr) => {
 
                            let variable = &heap[expr.declaration.unwrap()];
 
                            let ref_value = if expr.used_as_binding_target {
 
                                Value::Binding(variable.unique_id_in_scope as StackPos)
 
                            } else {
 
                                Value::Ref(ValueId::Stack(variable.unique_id_in_scope as StackPos))
 
                            };
 
                            cur_frame.expr_values.push_back(ref_value);
 
                        }
 
                    }
 
                }
 
            }
 
        }
 

	
 
        debug_log!("Frame [{:?}] at {:?}", cur_frame.definition, cur_frame.position);
 
        if debug_enabled!() {
 
            debug_log!("Expression value stack (size = {}):", cur_frame.expr_values.len());
 
            for (_stack_idx, _stack_val) in cur_frame.expr_values.iter().enumerate() {
 
                debug_log!("  [{:03}] {:?}", _stack_idx, _stack_val);
 
            }
 

	
 
            debug_log!("Stack (size = {}):", self.store.stack.len());
 
            for (_stack_idx, _stack_val) in self.store.stack.iter().enumerate() {
 
                debug_log!("  [{:03}] {:?}", _stack_idx, _stack_val);
 
            }
 

	
 
            debug_log!("Heap:");
 
            for (_heap_idx, _heap_region) in self.store.heap_regions.iter().enumerate() {
 
                let _is_free = self.store.free_regions.iter().any(|idx| *idx as usize == _heap_idx);
 
                debug_log!("  [{:03}] in_use: {}, len: {}, vals: {:?}", _heap_idx, !_is_free, _heap_region.values.len(), &_heap_region.values);
 
            }
 
        }
 
        // No (more) expressions to evaluate. So evaluate statement (that may
 
        // depend on the result on the last evaluated expression(s))
 
        let stmt = &heap[cur_frame.position];
 
        let return_value = match stmt {
 
            Statement::Block(stmt) => {
 
                debug_assert!(stmt.statements.is_empty() || stmt.next == stmt.statements[0]);
 
                cur_frame.position = stmt.next;
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::EndBlock(stmt) => {
 
                let block = &heap[stmt.start_block];
 
                let scope = &heap[block.scope];
 
                self.store.clear_stack(scope.first_unique_id_in_scope as usize);
 
                cur_frame.position = stmt.next;
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::Local(stmt) => {
 
                match stmt {
 
                    LocalStatement::Memory(stmt) => {
 
                        dbg_code!({
 
                            let variable = &heap[stmt.variable];
 
                            debug_assert!(match self.store.read_ref(ValueId::Stack(variable.unique_id_in_scope as u32)) {
 
                                Value::Unassigned => false,
 
                                _ => true,
 
                            });
 
                        });
 

	
 
                        cur_frame.position = stmt.next;
 
                        Ok(EvalContinuation::Stepping)
 
                    },
 
                    LocalStatement::Channel(stmt) => {
 
                        // Need to create a new channel by requesting it from
 
                        // the runtime.
 
                        match ctx.created_channel() {
 
                            None => {
 
                                // No channel is pending. So request one
 
                                    Ok(EvalContinuation::NewChannel)
 
                            },
 
                            Some((put_port, get_port)) => {
 
                                self.store.write(ValueId::Stack(heap[stmt.from].unique_id_in_scope as u32), put_port);
 
                                self.store.write(ValueId::Stack(heap[stmt.to].unique_id_in_scope as u32), get_port);
 
                                cur_frame.position = stmt.next;
 
                                Ok(EvalContinuation::Stepping)
 
                            }
 
                        }
 
                    }
 
                }
 
            },
 
            Statement::Labeled(stmt) => {
 
                cur_frame.position = stmt.body;
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::If(stmt) => {
 
                debug_assert_eq!(cur_frame.expr_values.len(), 1, "expected one expr value for if statement");
 
                let test_value = cur_frame.expr_values.pop_back().unwrap();
 
                let test_value = self.store.maybe_read_ref(&test_value).as_bool();
 
                if test_value {
 
                    cur_frame.position = stmt.true_case.body;
 
                } else if let Some(false_body) = stmt.false_case {
 
                    cur_frame.position = false_body.body;
 
                } else {
 
                    // Not true, and no false body
 
                    cur_frame.position = stmt.end_if.upcast();
 
                }
 

	
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::EndIf(stmt) => {
 
                cur_frame.position = stmt.next;
 
                let if_stmt = &heap[stmt.start_if];
 
                debug_assert_eq!(
 
                    heap[if_stmt.true_case.scope].first_unique_id_in_scope,
 
                    heap[if_stmt.false_case.unwrap_or(if_stmt.true_case).scope].first_unique_id_in_scope,
 
                );
 
                let scope = &heap[if_stmt.true_case.scope];
 
                self.store.clear_stack(scope.first_unique_id_in_scope as usize);
 
                Ok(EvalContinuation::Stepping)
 
            },
 
            Statement::While(stmt) => {
 
                debug_assert_eq!(cur_frame.expr_values.len(), 1, "expected one expr value for while statement");
 
                let test_value = cur_frame.expr_values.pop_back().unwrap();
 
                let test_value = self.store.maybe_read_ref(&test_value).as_bool();
 
                if test_value {
 
                    cur_frame.position = stmt.body;
 
                } else {
 
                    cur_frame.position = stmt.end_while.upcast();
 
                }
 

	
src/protocol/parser/pass_definitions.rs
Show inline comments
 
@@ -1334,389 +1334,403 @@ impl PassDefinitions {
 
            match token.unwrap() {
 
                TK::PlusPlus | TK::MinusMinus | TK::OpenSquare | TK::Dot => true,
 
                _ => false
 
            }
 
        }
 

	
 
        let mut result = self.consume_primary_expression(module, iter, ctx)?;
 
        let mut next = iter.next();
 
        while has_matching_postfix_token(next) {
 
            let token = next.unwrap();
 
            let mut operator_span = iter.next_span();
 
            iter.consume();
 

	
 
            if token == TokenKind::PlusPlus {
 
                return Err(ParseError::new_error_str_at_span(
 
                    &module.source, operator_span, "postfix increment is not supported in this language"
 
                ));
 
            } else if token == TokenKind::MinusMinus {
 
                return Err(ParseError::new_error_str_at_span(
 
                    &module.source, operator_span, "prefix increment is not supported in this language"
 
                ));
 
            } else if token == TokenKind::OpenSquare {
 
                let subject = result;
 
                let from_index = self.consume_expression(module, iter, ctx)?;
 

	
 
                // Check if we have an indexing or slicing operation
 
                next = iter.next();
 
                if Some(TokenKind::DotDot) == next {
 
                    iter.consume();
 

	
 
                    let to_index = self.consume_expression(module, iter, ctx)?;
 
                    let end_span = consume_token(&module.source, iter, TokenKind::CloseSquare)?;
 
                    operator_span.end = end_span.end;
 
                    let full_span = InputSpan::from_positions(
 
                        ctx.heap[subject].full_span().begin, operator_span.end
 
                    );
 

	
 
                    result = ctx.heap.alloc_slicing_expression(|this| SlicingExpression{
 
                        this,
 
                        slicing_span: operator_span,
 
                        full_span, subject, from_index, to_index,
 
                        parent: ExpressionParent::None,
 
                        type_index: -1,
 
                    }).upcast();
 
                } else if Some(TokenKind::CloseSquare) == next {
 
                    let end_span = consume_token(&module.source, iter, TokenKind::CloseSquare)?;
 
                    operator_span.end = end_span.end;
 

	
 
                    let full_span = InputSpan::from_positions(
 
                        ctx.heap[subject].full_span().begin, operator_span.end
 
                    );
 

	
 
                    result = ctx.heap.alloc_indexing_expression(|this| IndexingExpression{
 
                        this, operator_span, full_span, subject,
 
                        index: from_index,
 
                        parent: ExpressionParent::None,
 
                        type_index: -1,
 
                    }).upcast();
 
                } else {
 
                    return Err(ParseError::new_error_str_at_pos(
 
                        &module.source, iter.last_valid_pos(), "unexpected token: expected ']' or '..'"
 
                    ));
 
                }
 
            } else {
 
                // Can be a select expression for struct fields, or a select
 
                // for a tuple element.
 
                debug_assert_eq!(token, TokenKind::Dot);
 
                let subject = result;
 

	
 
                let next = iter.next();
 
                let (select_kind, full_span) = if Some(TokenKind::Integer) == next {
 
                    // Tuple member
 
                    let (index, index_span) = consume_integer_literal(&module.source, iter, &mut self.buffer)?;
 
                    let full_span = InputSpan::from_positions(
 
                        ctx.heap[subject].full_span().begin, index_span.end
 
                    );
 

	
 
                    (SelectKind::TupleMember(index), full_span)
 
                } else if Some(TokenKind::Ident) == next {
 
                    // Struct field
 
                    let field_name = consume_ident_interned(&module.source, iter, ctx)?;
 

	
 
                    let full_span = InputSpan::from_positions(
 
                        ctx.heap[subject].full_span().begin, field_name.span.end
 
                    );
 

	
 
                    (SelectKind::StructField(field_name), full_span)
 
                } else {
 
                    return Err(ParseError::new_error_str_at_pos(
 
                        &module.source, iter.last_valid_pos(), "unexpected token: expected integer or identifier"
 
                    ));
 
                };
 

	
 
                result = ctx.heap.alloc_select_expression(|this| SelectExpression{
 
                    this, operator_span, full_span, subject,
 
                    kind: select_kind,
 
                    parent: ExpressionParent::None,
 
                    type_index: -1,
 
                }).upcast();
 
            }
 

	
 
            next = iter.next();
 
        }
 

	
 
        Ok(result)
 
    }
 

	
 
    fn consume_primary_expression(
 
        &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
 
    ) -> Result<ExpressionId, ParseError> {
 
        let next = iter.next();
 

	
 
        let result = if next == Some(TokenKind::OpenParen) {
 
            // Something parenthesized. This can mean several things: we have
 
            // a parenthesized expression or we have a tuple literal. They are
 
            // ambiguous when the tuple has one member. But like the tuple type
 
            // parsing we interpret all one-tuples as parenthesized expressions.
 
            //
 
            // Practically (to prevent unnecessary `consume_expression` calls)
 
            // we distinguish the zero-tuple, the parenthesized expression, and
 
            // the N-tuple (for N > 1).
 
            let open_paren_pos = iter.next_start_position();
 
            iter.consume();
 
            let result = if Some(TokenKind::CloseParen) == iter.next() {
 
                // Zero-tuple
 
                let (_, close_paren_pos) = iter.next_positions();
 
                iter.consume();
 

	
 
                let literal_id = ctx.heap.alloc_literal_expression(|this| LiteralExpression{
 
                    this,
 
                    span: InputSpan::from_positions(open_paren_pos, close_paren_pos),
 
                    value: Literal::Tuple(Vec::new()),
 
                    parent: ExpressionParent::None,
 
                    type_index: -1,
 
                });
 

	
 
                literal_id.upcast()
 
            } else {
 
                // Start by consuming one expression, then check for a comma
 
                let expr_id = self.consume_expression(module, iter, ctx)?;
 
                if Some(TokenKind::Comma) == iter.next() && Some(TokenKind::CloseParen) != iter.peek() {
 
                    // Must be an N-tuple
 
                    iter.consume(); // the comma
 
                    let mut scoped_section = self.expressions.start_section();
 
                    scoped_section.push(expr_id);
 

	
 
                    let mut close_paren_pos = open_paren_pos;
 
                    consume_comma_separated_until(
 
                        TokenKind::CloseParen, &module.source, iter, ctx,
 
                        |_source, iter, ctx| self.consume_expression(module, iter, ctx),
 
                        &mut scoped_section, "an expression", Some(&mut close_paren_pos)
 
                    )?;
 
                    debug_assert!(scoped_section.len() > 1); // peeked token wasn't CloseParen, must be expression
 

	
 
                    let literal_id = ctx.heap.alloc_literal_expression(|this| LiteralExpression{
 
                        this,
 
                        span: InputSpan::from_positions(open_paren_pos, close_paren_pos),
 
                        value: Literal::Tuple(scoped_section.into_vec()),
 
                        parent: ExpressionParent::None,
 
                        type_index: -1,
 
                    });
 

	
 
                    literal_id.upcast()
 
                } else {
 
                    // Assume we're dealing with a normal expression
 
                    consume_token(&module.source, iter, TokenKind::CloseParen)?;
 

	
 
                    expr_id
 
                }
 
            };
 

	
 
            result
 
        } else if next == Some(TokenKind::OpenCurly) {
 
            // Array literal
 
            let (start_pos, mut end_pos) = iter.next_positions();
 
            let mut scoped_section = self.expressions.start_section();
 
            consume_comma_separated(
 
                TokenKind::OpenCurly, TokenKind::CloseCurly, &module.source, iter, ctx,
 
                |_source, iter, ctx| self.consume_expression(module, iter, ctx),
 
                &mut scoped_section, "an expression", "a list of expressions", Some(&mut end_pos)
 
            )?;
 

	
 
            ctx.heap.alloc_literal_expression(|this| LiteralExpression{
 
                this,
 
                span: InputSpan::from_positions(start_pos, end_pos),
 
                value: Literal::Array(scoped_section.into_vec()),
 
                parent: ExpressionParent::None,
 
                type_index: -1,
 
            }).upcast()
 
        } else if next == Some(TokenKind::Integer) {
 
            let (literal, span) = consume_integer_literal(&module.source, iter, &mut self.buffer)?;
 

	
 
            ctx.heap.alloc_literal_expression(|this| LiteralExpression {
 
                this,
 
                span,
 
                value: Literal::Integer(LiteralInteger { unsigned_value: literal, negated: false }),
 
                parent: ExpressionParent::None,
 
                type_index: -1,
 
            }).upcast()
 
        } else if next == Some(TokenKind::Bytestring) {
 
            let span = consume_bytestring_literal(&module.source, iter, &mut self.buffer)?;
 
            let mut bytes = Vec::with_capacity(self.buffer.len());
 
            for byte in self.buffer.as_bytes().iter().copied() {
 
                bytes.push(byte);
 
            }
 

	
 
            ctx.heap.alloc_literal_expression(|this| LiteralExpression{
 
                this, span,
 
                value: Literal::Integer(LiteralInteger{ unsigned_value: literal, negated: false }),
 
                value: Literal::Bytestring(bytes),
 
                parent: ExpressionParent::None,
 
                type_index: -1,
 
                type_index: -1
 
            }).upcast()
 
        } else if next == Some(TokenKind::String) {
 
            let span = consume_string_literal(&module.source, iter, &mut self.buffer)?;
 
            let interned = ctx.pool.intern(self.buffer.as_bytes());
 

	
 
            ctx.heap.alloc_literal_expression(|this| LiteralExpression{
 
                this, span,
 
                value: Literal::String(interned),
 
                parent: ExpressionParent::None,
 
                type_index: -1,
 
            }).upcast()
 
        } else if next == Some(TokenKind::Character) {
 
            let (character, span) = consume_character_literal(&module.source, iter)?;
 

	
 
            ctx.heap.alloc_literal_expression(|this| LiteralExpression{
 
                this, span,
 
                value: Literal::Character(character),
 
                parent: ExpressionParent::None,
 
                type_index: -1,
 
            }).upcast()
 
        } else if next == Some(TokenKind::Ident) {
 
            // May be a variable, a type instantiation or a function call. If we
 
            // have a single identifier that we cannot find in the type table
 
            // then we're going to assume that we're dealing with a variable.
 

	
 
            let ident_span = iter.next_span();
 
            let ident_text = module.source.section_at_span(ident_span);
 
            let symbol = ctx.symbols.get_symbol_by_name(SymbolScope::Module(module.root_id), ident_text);
 

	
 
            if symbol.is_some() {
 
                // The first bit looked like a symbol, so we're going to follow
 
                // that all the way through, assume we arrive at some kind of
 
                // function call or type instantiation
 
                use ParserTypeVariant as PTV;
 

	
 
                let symbol_scope = SymbolScope::Definition(self.cur_definition);
 
                let poly_vars = ctx.heap[self.cur_definition].poly_vars();
 
                let parser_type = self.type_parser.consume_parser_type(
 
                    iter, &ctx.heap, &module.source, &ctx.symbols, poly_vars, self.cur_definition,
 
                    symbol_scope, true, false, None
 
                )?;
 
                debug_assert!(!parser_type.elements.is_empty());
 
                match parser_type.elements[0].variant {
 
                    PTV::Definition(target_definition_id, _) => {
 
                        let definition = &ctx.heap[target_definition_id];
 
                        match definition {
 
                            Definition::Struct(_) => {
 
                                // Struct literal
 
                                let mut last_token = iter.last_valid_pos();
 
                                let mut struct_fields = Vec::new();
 
                                consume_comma_separated(
 
                                    TokenKind::OpenCurly, TokenKind::CloseCurly, &module.source, iter, ctx,
 
                                    |source, iter, ctx| {
 
                                        let identifier = consume_ident_interned(source, iter, ctx)?;
 
                                        consume_token(source, iter, TokenKind::Colon)?;
 
                                        let value = self.consume_expression(module, iter, ctx)?;
 
                                        Ok(LiteralStructField{ identifier, value, field_idx: 0 })
 
                                    },
 
                                    &mut struct_fields, "a struct field", "a list of struct fields", Some(&mut last_token)
 
                                )?;
 

	
 
                                ctx.heap.alloc_literal_expression(|this| LiteralExpression{
 
                                    this,
 
                                    span: InputSpan::from_positions(ident_span.begin, last_token),
 
                                    value: Literal::Struct(LiteralStruct{
 
                                        parser_type,
 
                                        fields: struct_fields,
 
                                        definition: target_definition_id,
 
                                    }),
 
                                    parent: ExpressionParent::None,
 
                                    type_index: -1,
 
                                }).upcast()
 
                            },
 
                            Definition::Enum(_) => {
 
                                // Enum literal: consume the variant
 
                                consume_token(&module.source, iter, TokenKind::ColonColon)?;
 
                                let variant = consume_ident_interned(&module.source, iter, ctx)?;
 

	
 
                                ctx.heap.alloc_literal_expression(|this| LiteralExpression{
 
                                    this,
 
                                    span: InputSpan::from_positions(ident_span.begin, variant.span.end),
 
                                    value: Literal::Enum(LiteralEnum{
 
                                        parser_type,
 
                                        variant,
 
                                        definition: target_definition_id,
 
                                        variant_idx: 0
 
                                    }),
 
                                    parent: ExpressionParent::None,
 
                                    type_index: -1,
 
                                }).upcast()
 
                            },
 
                            Definition::Union(_) => {
 
                                // Union literal: consume the variant
 
                                consume_token(&module.source, iter, TokenKind::ColonColon)?;
 
                                let variant = consume_ident_interned(&module.source, iter, ctx)?;
 

	
 
                                // Consume any possible embedded values
 
                                let mut end_pos = variant.span.end;
 
                                let values = if Some(TokenKind::OpenParen) == iter.next() {
 
                                    self.consume_expression_list(module, iter, ctx, Some(&mut end_pos))?
 
                                } else {
 
                                    Vec::new()
 
                                };
 

	
 
                                ctx.heap.alloc_literal_expression(|this| LiteralExpression{
 
                                    this,
 
                                    span: InputSpan::from_positions(ident_span.begin, end_pos),
 
                                    value: Literal::Union(LiteralUnion{
 
                                        parser_type, variant, values,
 
                                        definition: target_definition_id,
 
                                        variant_idx: 0,
 
                                    }),
 
                                    parent: ExpressionParent::None,
 
                                    type_index: -1,
 
                                }).upcast()
 
                            },
 
                            Definition::Procedure(proc_def) => {
 
                                // Check whether it is a builtin function
 
                                // TODO: Once we start generating bytecode this is unnecessary
 
                                let procedure_id = proc_def.this;
 
                                let method = match proc_def.source {
 
                                    ProcedureSource::FuncUserDefined => Method::UserFunction,
 
                                    ProcedureSource::CompUserDefined => Method::UserComponent,
 
                                    ProcedureSource::FuncGet => Method::Get,
 
                                    ProcedureSource::FuncPut => Method::Put,
 
                                    ProcedureSource::FuncFires => Method::Fires,
 
                                    ProcedureSource::FuncCreate => Method::Create,
 
                                    ProcedureSource::FuncLength => Method::Length,
 
                                    ProcedureSource::FuncAssert => Method::Assert,
 
                                    ProcedureSource::FuncPrint => Method::Print,
 
                                    ProcedureSource::CompRandomU32 => Method::ComponentRandomU32,
 
                                    ProcedureSource::CompTcpClient => Method::ComponentTcpClient,
 
                                    _ => todo!("other procedure sources"),
 
                                };
 

	
 
                                // Function call: consume the arguments
 
                                let func_span = parser_type.full_span;
 
                                let mut full_span = func_span;
 
                                let arguments = self.consume_expression_list(
 
                                    module, iter, ctx, Some(&mut full_span.end)
 
                                )?;
 

	
 
                                ctx.heap.alloc_call_expression(|this| CallExpression{
 
                                    this, func_span, full_span, parser_type, method, arguments,
 
                                    procedure: procedure_id,
 
                                    parent: ExpressionParent::None,
 
                                    type_index: -1,
 
                                }).upcast()
 
                            }
 
                        }
 
                    },
 
                    _ => {
 
                        return Err(ParseError::new_error_str_at_span(
 
                            &module.source, parser_type.full_span, "unexpected type in expression"
 
                        ))
 
                    }
 
                }
 
            } else {
 
                // Check for builtin keywords or builtin functions
 
                if ident_text == KW_LIT_NULL || ident_text == KW_LIT_TRUE || ident_text == KW_LIT_FALSE {
 
                    iter.consume();
 

	
 
                    // Parse builtin literal
 
                    let value = match ident_text {
 
                        KW_LIT_NULL => Literal::Null,
 
                        KW_LIT_TRUE => Literal::True,
 
                        KW_LIT_FALSE => Literal::False,
 
                        _ => unreachable!(),
 
                    };
 

	
 
                    ctx.heap.alloc_literal_expression(|this| LiteralExpression {
 
                        this,
 
                        span: ident_span,
 
                        value,
 
                        parent: ExpressionParent::None,
 
                        type_index: -1,
 
                    }).upcast()
 
                } else if ident_text == KW_LET {
 
                    // Binding expression
 
                    let operator_span = iter.next_span();
 
                    iter.consume();
 

	
 
                    let bound_to = self.consume_prefix_expression(module, iter, ctx)?;
 
                    consume_token(&module.source, iter, TokenKind::Equal)?;
 
                    let bound_from = self.consume_prefix_expression(module, iter, ctx)?;
 

	
 
                    let full_span = InputSpan::from_positions(
 
                        operator_span.begin, ctx.heap[bound_from].full_span().end,
 
                    );
 

	
 
                    ctx.heap.alloc_binding_expression(|this| BindingExpression{
 
                        this, operator_span, full_span, bound_to, bound_from,
src/protocol/parser/pass_tokenizer.rs
Show inline comments
 
use crate::protocol::input_source::{
 
    InputSource as InputSource,
 
    ParseError,
 
    InputPosition as InputPosition,
 
};
 

	
 
use super::tokens::*;
 
use super::token_parsing::*;
 

	
 
/// Tokenizer is a reusable parser to tokenize multiple source files using the
 
/// same allocated buffers. In a well-formed program, we produce a consistent
 
/// tree of token ranges such that we may identify tokens that represent a
 
/// defintion or an import before producing the entire AST.
 
///
 
/// If the program is not well-formed then the tree may be inconsistent, but we
 
/// will detect this once we transform the tokens into the AST. To ensure a
 
/// consistent AST-producing phase we will require the import to have balanced
 
/// curly braces
 
pub(crate) struct PassTokenizer {
 
    // Stack of input positions of opening curly braces, used to detect
 
    // unmatched opening braces, unmatched closing braces are detected
 
    // immediately.
 
    curly_stack: Vec<InputPosition>,
 
}
 

	
 
impl PassTokenizer {
 
    pub(crate) fn new() -> Self {
 
        Self{
 
            curly_stack: Vec::with_capacity(32),
 
        }
 
    }
 

	
 
    pub(crate) fn tokenize(&mut self, source: &mut InputSource, target: &mut TokenBuffer) -> Result<(), ParseError> {
 
        // Assert source and buffer are at start
 
        debug_assert_eq!(source.pos().offset, 0);
 
        debug_assert!(target.tokens.is_empty());
 

	
 
        // Main tokenization loop
 
        while let Some(c) = source.next() {
 
            let token_index = target.tokens.len() as u32;
 

	
 
            if is_char_literal_start(c) {
 
                self.consume_char_literal(source, target)?;
 
            } else if is_bytestring_literal_start(c, source) {
 
                self.consume_bytestring_literal(source, target)?;
 
            } else if is_string_literal_start(c) {
 
                self.consume_string_literal(source, target)?;
 
            } else if is_identifier_start(c) {
 
                let ident = self.consume_identifier(source, target)?;
 

	
 
                if demarks_symbol(ident) {
 
                    self.emit_marker(target, TokenMarkerKind::Definition, token_index);
 
                } else if demarks_import(ident) {
 
                    self.emit_marker(target, TokenMarkerKind::Import, token_index);
 
                }
 
            } else if is_integer_literal_start(c) {
 
                self.consume_number(source, target)?;
 
            } else if is_pragma_start_or_pound(c) {
 
                let was_pragma = self.consume_pragma_or_pound(c, source, target)?;
 
                if was_pragma {
 
                    self.emit_marker(target, TokenMarkerKind::Pragma, token_index);
 
                }
 
            } else if self.is_line_comment_start(c, source) {
 
                self.consume_line_comment(source, target)?;
 
            } else if self.is_block_comment_start(c, source) {
 
                self.consume_block_comment(source, target)?;
 
            } else if is_whitespace(c) {
 
                self.consume_whitespace(source);
 
            } else {
 
                let was_punctuation = self.maybe_parse_punctuation(c, source, target)?;
 
                if let Some((token, token_pos)) = was_punctuation {
 
                    if token == TokenKind::OpenCurly {
 
                        self.curly_stack.push(token_pos);
 
                    } else if token == TokenKind::CloseCurly {
 
                        // Check if this marks the end of a range we're
 
                        // currently processing
 
                        if self.curly_stack.is_empty() {
 
                            return Err(ParseError::new_error_str_at_pos(
 
                                source, token_pos, "unmatched closing curly brace '}'"
 
                            ));
 
                        }
 

	
 
                        self.curly_stack.pop();
 
                    }
 
                } else {
 
                    return Err(ParseError::new_error_str_at_pos(
 
                        source, source.pos(), "unexpected character"
 
                    ));
 
                }
 
            }
 
        }
 

	
 
        // End of file, check if our state is correct
 
        if let Some(error) = source.had_error.take() {
 
            return Err(error);
 
        }
 

	
 
        if !self.curly_stack.is_empty() {
 
            // Let's not add a lot of heuristics and just tell the programmer
 
            // that something is wrong
 
            let last_unmatched_open = self.curly_stack.pop().unwrap();
 
            return Err(ParseError::new_error_str_at_pos(
 
                source, last_unmatched_open, "unmatched opening curly brace '{'"
 
            ));
 
        }
 

	
 
        Ok(())
 
    }
 

	
 
    fn is_line_comment_start(&self, first_char: u8, source: &InputSource) -> bool {
 
        return first_char == b'/' && Some(b'/') == source.lookahead(1);
 
    }
 

	
 
    fn is_block_comment_start(&self, first_char: u8, source: &InputSource) -> bool {
 
        return first_char == b'/' && Some(b'*') == source.lookahead(1);
 
    }
 

	
 
    fn maybe_parse_punctuation(
 
        &mut self, first_char: u8, source: &mut InputSource, target: &mut TokenBuffer
 
    ) -> Result<Option<(TokenKind, InputPosition)>, ParseError> {
 
        debug_assert!(first_char != b'#', "'#' needs special handling");
 
        debug_assert!(first_char != b'\'', "'\'' needs special handling");
 
        debug_assert!(first_char != b'"', "'\"' needs special handling");
 

	
 
        let pos = source.pos();
 
        let token_kind;
 
        if first_char == b'!' {
 
            source.consume();
 
            if Some(b'=') == source.next() {
 
                source.consume();
 
                token_kind = TokenKind::NotEqual;
 
            } else {
 
                token_kind = TokenKind::Exclamation;
 
            }
 
        } else if first_char == b'%' {
 
            source.consume();
 
            if Some(b'=') == source.next() {
 
                source.consume();
 
                token_kind = TokenKind::PercentEquals;
 
            } else {
 
                token_kind = TokenKind::Percent;
 
            }
 
        } else if first_char == b'&' {
 
            source.consume();
 
            let next = source.next();
 
            if Some(b'&') == next {
 
                source.consume();
 
                token_kind = TokenKind::AndAnd;
 
            } else if Some(b'=') == next {
 
                source.consume();
 
                token_kind = TokenKind::AndEquals;
 
            } else {
 
                token_kind = TokenKind::And;
 
            }
 
        } else if first_char == b'(' {
 
            source.consume();
 
            token_kind = TokenKind::OpenParen;
 
        } else if first_char == b')' {
 
            source.consume();
 
            token_kind = TokenKind::CloseParen;
 
        } else if first_char == b'*' {
 
            source.consume();
 
            if let Some(b'=') = source.next() {
 
                source.consume();
 
                token_kind = TokenKind::StarEquals;
 
            } else {
 
                token_kind = TokenKind::Star;
 
            }
 
        } else if first_char == b'+' {
 
            source.consume();
 
            let next = source.next();
 
            if Some(b'+') == next {
 
                source.consume();
 
                token_kind = TokenKind::PlusPlus;
 
            } else if Some(b'=') == next {
 
                source.consume();
 
                token_kind = TokenKind::PlusEquals;
 
            } else {
 
                token_kind = TokenKind::Plus;
 
            }
 
        } else if first_char == b',' {
 
            source.consume();
 
            token_kind = TokenKind::Comma;
 
        } else if first_char == b'-' {
 
            source.consume();
 
            let next = source.next();
 
            if Some(b'-') == next {
 
                source.consume();
 
                token_kind = TokenKind::MinusMinus;
 
            } else if Some(b'>') == next {
 
                source.consume();
 
                token_kind = TokenKind::ArrowRight;
 
            } else if Some(b'=') == next {
 
                source.consume();
 
                token_kind = TokenKind::MinusEquals;
 
            } else {
 
                token_kind = TokenKind::Minus;
 
            }
 
        } else if first_char == b'.' {
 
            source.consume();
 
            if let Some(b'.') = source.next() {
 
                source.consume();
 
                token_kind = TokenKind::DotDot;
 
            } else {
 
                token_kind = TokenKind::Dot
 
            }
 
        } else if first_char == b'/' {
 
            source.consume();
 
            debug_assert_ne!(Some(b'/'), source.next());
 
            debug_assert_ne!(Some(b'*'), source.next());
 
            if let Some(b'=') = source.next() {
 
                source.consume();
 
                token_kind = TokenKind::SlashEquals;
 
            } else {
 
                token_kind = TokenKind::Slash;
 
            }
 
        } else if first_char == b':' {
 
            source.consume();
 
            if let Some(b':') = source.next() {
 
                source.consume();
 
                token_kind = TokenKind::ColonColon;
 
            } else {
 
                token_kind = TokenKind::Colon;
 
            }
 
        } else if first_char == b';' {
 
            source.consume();
 
            token_kind = TokenKind::SemiColon;
 
        } else if first_char == b'<' {
 
            source.consume();
 
            let next = source.next();
 
            if let Some(b'<') = next {
 
                source.consume();
 
                if let Some(b'=') = source.next() {
 
                    source.consume();
 
                    token_kind = TokenKind::ShiftLeftEquals;
 
                } else {
 
                    token_kind = TokenKind::ShiftLeft;
 
                }
 
            } else if let Some(b'=') = next {
 
                source.consume();
 
                token_kind = TokenKind::LessEquals;
 
            } else {
 
                token_kind = TokenKind::OpenAngle;
 
            }
 
        } else if first_char == b'=' {
 
            source.consume();
 
            if let Some(b'=') = source.next() {
 
                source.consume();
 
                token_kind = TokenKind::EqualEqual;
 
            } else {
 
                token_kind = TokenKind::Equal;
 
            }
 
        } else if first_char == b'>' {
 
            source.consume();
 
            let next = source.next();
 
            if Some(b'>') == next {
 
                source.consume();
 
                if Some(b'=') == source.next() {
 
                    source.consume();
 
                    token_kind = TokenKind::ShiftRightEquals;
 
                } else {
 
                    token_kind = TokenKind::ShiftRight;
 
                }
 
            } else if Some(b'=') == next {
 
                source.consume();
 
                token_kind = TokenKind::GreaterEquals;
 
            } else {
 
                token_kind = TokenKind::CloseAngle;
 
            }
 
        } else if first_char == b'?' {
 
            source.consume();
 
            token_kind = TokenKind::Question;
 
        } else if first_char == b'@' {
 
            source.consume();
 
            if let Some(b'=') = source.next() {
 
                source.consume();
 
                token_kind = TokenKind::AtEquals;
 
            } else {
 
                token_kind = TokenKind::At;
 
            }
 
        } else if first_char == b'[' {
 
            source.consume();
 
            token_kind = TokenKind::OpenSquare;
 
        } else if first_char == b']' {
 
            source.consume();
 
            token_kind = TokenKind::CloseSquare;
 
        } else if first_char == b'^' {
 
            source.consume();
 
            if let Some(b'=') = source.next() {
 
                source.consume();
 
                token_kind = TokenKind::CaretEquals;
 
            } else {
 
                token_kind = TokenKind::Caret;
 
            }
 
        } else if first_char == b'{' {
 
            source.consume();
 
            token_kind = TokenKind::OpenCurly;
 
        } else if first_char == b'|' {
 
            source.consume();
 
            let next = source.next();
 
            if Some(b'|') == next {
 
                source.consume();
 
                token_kind = TokenKind::OrOr;
 
            } else if Some(b'=') == next {
 
                source.consume();
 
                token_kind = TokenKind::OrEquals;
 
            } else {
 
                token_kind = TokenKind::Or;
 
            }
 
        } else if first_char == b'}' {
 
            source.consume();
 
            token_kind = TokenKind::CloseCurly;
 
        } else if first_char == b'~' {
 
            source.consume();
 
            token_kind = TokenKind::Tilde;
 
        } else {
 
            self.check_ascii(source)?;
 
            return Ok(None);
 
        }
 

	
 
        target.tokens.push(Token::new(token_kind, pos));
 
        Ok(Some((token_kind, pos)))
 
    }
 

	
 
    fn consume_char_literal(&mut self, source: &mut InputSource, target: &mut TokenBuffer) -> Result<(), ParseError> {
 
        let begin_pos = source.pos();
 

	
 
        // Consume the leading quote
 
        debug_assert!(source.next().unwrap() == b'\'');
 
        source.consume();
 

	
 
        let mut prev_char = b'\'';
 
        while let Some(c) = source.next() {
 
            if !c.is_ascii() {
 
                return Err(ParseError::new_error_str_at_pos(source, source.pos(), "non-ASCII character in char literal"));
 
            }
 
            source.consume();
 

	
 
            // Make sure ending quote was not escaped
 
            if c == b'\'' && prev_char != b'\\' {
 
                prev_char = c;
 
                break;
 
            }
 

	
 
            prev_char = c;
 
        }
 

	
 
        if prev_char != b'\'' {
 
            // Unterminated character literal, reached end of file.
 
            return Err(ParseError::new_error_str_at_pos(source, begin_pos, "encountered unterminated character literal"));
 
        }
 

	
 
        let end_pos = source.pos();
 

	
 
        target.tokens.push(Token::new(TokenKind::Character, begin_pos));
 
        target.tokens.push(Token::new(TokenKind::SpanEnd, end_pos));
 

	
 
        Ok(())
 
    }
 

	
 
    fn consume_string_literal(&mut self, source: &mut InputSource, target: &mut TokenBuffer) -> Result<(), ParseError> {
 
    fn consume_bytestring_literal(&mut self, source: &mut InputSource, target: &mut TokenBuffer) -> Result<(), ParseError> {
 
        let begin_pos = source.pos();
 

	
 
        // Consume the leading double quotes
 
        debug_assert!(source.next().unwrap() == b'"');
 
        debug_assert!(source.next().unwrap() == b'b');
 
        source.consume();
 

	
 
        let mut prev_char = b'"';
 
        while let Some(c) = source.next() {
 
            if !c.is_ascii() {
 
                return Err(ParseError::new_error_str_at_pos(source, source.pos(), "non-ASCII character in string literal"));
 
            }
 

	
 
            source.consume();
 
            if c == b'"' && prev_char != b'\\' {
 
                // Unescaped string terminator
 
                prev_char = c;
 
                break;
 
            }
 

	
 
            if prev_char == b'\\' && c == b'\\' {
 
                // Escaped backslash, set prev_char to bogus to not conflict
 
                // with escaped-" and unterminated string literal detection.
 
                prev_char = b'\0';
 
            } else {
 
                prev_char = c;
 
            }
 
        }
 
        let end_pos = self.consume_ascii_string(begin_pos, source)?;
 
        target.tokens.push(Token::new(TokenKind::Bytestring, begin_pos));
 
        target.tokens.push(Token::new(TokenKind::SpanEnd, end_pos));
 

	
 
        if prev_char != b'"' {
 
            // Unterminated string literal
 
            return Err(ParseError::new_error_str_at_pos(source, begin_pos, "encountered unterminated string literal"));
 
        }
 
        Ok(())
 
    }
 

	
 
        let end_pos = source.pos();
 
    fn consume_string_literal(&mut self, source: &mut InputSource, target: &mut TokenBuffer) -> Result<(), ParseError> {
 
        let begin_pos = source.pos();
 
        let end_pos = self.consume_ascii_string(begin_pos, source)?;
 
        target.tokens.push(Token::new(TokenKind::String, begin_pos));
 
        target.tokens.push(Token::new(TokenKind::SpanEnd, end_pos));
 

	
 
        Ok(())
 
    }
 

	
 
    fn consume_pragma_or_pound(&mut self, first_char: u8, source: &mut InputSource, target: &mut TokenBuffer) -> Result<bool, ParseError> {
 
        let start_pos = source.pos();
 
        debug_assert_eq!(first_char, b'#');
 
        source.consume();
 

	
 
        let next = source.next();
 
        if next.is_none() || !is_identifier_start(next.unwrap()) {
 
            // Just a pound sign
 
            target.tokens.push(Token::new(TokenKind::Pound, start_pos));
 
            Ok(false)
 
        } else {
 
            // Pound sign followed by identifier
 
            source.consume();
 
            while let Some(c) = source.next() {
 
                if !is_identifier_remaining(c) {
 
                    break;
 
                }
 
                source.consume();
 
            }
 

	
 
            self.check_ascii(source)?;
 

	
 
            let end_pos = source.pos();
 
            target.tokens.push(Token::new(TokenKind::Pragma, start_pos));
 
            target.tokens.push(Token::new(TokenKind::SpanEnd, end_pos));
 
            Ok(true)
 
        }
 
    }
 

	
 
    fn consume_line_comment(&mut self, source: &mut InputSource, target: &mut TokenBuffer) -> Result<(), ParseError> {
 
        let begin_pos = source.pos();
 

	
 
        // Consume the leading "//"
 
        debug_assert!(source.next().unwrap() == b'/' && source.lookahead(1).unwrap() == b'/');
 
        source.consume();
 
        source.consume();
 

	
 
        let mut prev_char = b'/';
 
        let mut cur_char = b'/';
 
        while let Some(c) = source.next() {
 
            prev_char = cur_char;
 
            cur_char = c;
 

	
 
            if c == b'\n' {
 
                // End of line, note that the newline is not consumed
 
                break;
 
            }
 

	
 
            source.consume();
 
        }
 

	
 
        let mut end_pos = source.pos();
 
        debug_assert_eq!(begin_pos.line, end_pos.line);
 

	
 
        // Modify offset to not include the newline characters
 
        if cur_char == b'\n' {
 
            if prev_char == b'\r' {
 
                end_pos.offset -= 1;
 
            }
 

	
 
            // Consume final newline
 
            source.consume();
 
        } else {
 
            // End of comment was due to EOF
 
            debug_assert!(source.next().is_none())
 
        }
 

	
 
        target.tokens.push(Token::new(TokenKind::LineComment, begin_pos));
 
        target.tokens.push(Token::new(TokenKind::SpanEnd, end_pos));
 

	
 
        Ok(())
 
    }
 

	
 
    fn consume_block_comment(&mut self, source: &mut InputSource, target: &mut TokenBuffer) -> Result<(), ParseError> {
 
        let begin_pos = source.pos();
 

	
 
        // Consume the leading "/*"
 
        debug_assert!(source.next().unwrap() == b'/' && source.lookahead(1).unwrap() == b'*');
 
        source.consume();
 
        source.consume();
 

	
 
        // Explicitly do not put prev_char at "*", because then "/*/" would
 
        // represent a valid and closed block comment
 
        let mut prev_char = b' ';
 
        let mut is_closed = false;
 
        while let Some(c) = source.next() {
 
            source.consume();
 
            if prev_char == b'*' && c == b'/' {
 
                // End of block comment
 
                is_closed = true;
 
                break;
 
            }
 
            prev_char = c;
 
        }
 

	
 
        if !is_closed {
 
            return Err(ParseError::new_error_str_at_pos(
 
                source, source.pos(), "encountered unterminated block comment")
 
            );
 
        }
 

	
 
        let end_pos = source.pos();
 
        target.tokens.push(Token::new(TokenKind::BlockComment, begin_pos));
 
        target.tokens.push(Token::new(TokenKind::SpanEnd, end_pos));
 

	
 
        Ok(())
 
    }
 

	
 
    fn consume_identifier<'a>(&mut self, source: &'a mut InputSource, target: &mut TokenBuffer) -> Result<&'a [u8], ParseError> {
 
        let begin_pos = source.pos();
 
        debug_assert!(is_identifier_start(source.next().unwrap()));
 
        source.consume();
 

	
 
        // Keep reading until no more identifier
 
        while let Some(c) = source.next() {
 
            if !is_identifier_remaining(c) {
 
                break;
 
            }
 

	
 
            source.consume();
 
        }
 
        self.check_ascii(source)?;
 

	
 
        let end_pos = source.pos();
 
        target.tokens.push(Token::new(TokenKind::Ident, begin_pos));
 
        target.tokens.push(Token::new(TokenKind::SpanEnd, end_pos));
 
        Ok(source.section_at_pos(begin_pos, end_pos))
 
    }
 

	
 
    fn consume_number(&mut self, source: &mut InputSource, target: &mut TokenBuffer) -> Result<(), ParseError> {
 
        let begin_pos = source.pos();
 
        debug_assert!(is_integer_literal_start(source.next().unwrap()));
 
        source.consume();
 

	
 
        // Keep reading until it doesn't look like a number anymore
 
        while let Some(c) = source.next() {
 
            if !maybe_number_remaining(c) {
 
                break;
 
            }
 

	
 
            source.consume();
 
        }
 
        self.check_ascii(source)?;
 

	
 
        let end_pos = source.pos();
 
        target.tokens.push(Token::new(TokenKind::Integer, begin_pos));
 
        target.tokens.push(Token::new(TokenKind::SpanEnd, end_pos));
 

	
 
        Ok(())
 
    }
 

	
 
    // Consumes the ascii string (including leading and trailing quotation
 
    // marks) and returns the input position *after* the last quotation mark (or
 
    // an error, if something went wrong).
 
    fn consume_ascii_string(&self, begin_pos: InputPosition, source: &mut InputSource) -> Result<InputPosition, ParseError> {
 
        debug_assert!(source.next().unwrap() == b'"');
 
        source.consume();
 

	
 
        let mut prev_char = b'"';
 
        while let Some(c) = source.next() {
 
            if !c.is_ascii() {
 
                return Err(ParseError::new_error_str_at_pos(source, source.pos(), "non-ASCII character in string literal"));
 
            }
 

	
 
            source.consume();
 
            if c == b'"' && prev_char != b'\\' {
 
                // Unescaped string terminator
 
                prev_char = c;
 
                break;
 
            }
 

	
 
            if prev_char == b'\\' && c == b'\\' {
 
                // Escaped backslash, set prev_char to bogus to not conflict
 
                // with escaped-" and unterminated string literal detection.
 
                prev_char = b'\0';
 
            } else {
 
                prev_char = c;
 
            }
 
        }
 

	
 
        if prev_char != b'"' {
 
            // Unterminated string literal
 
            return Err(ParseError::new_error_str_at_pos(source, begin_pos, "encountered unterminated string literal"));
 
        }
 

	
 
        let end_pos = source.pos();
 
        return Ok(end_pos)
 
    }
 

	
 
    // Consumes whitespace and returns whether or not the whitespace contained
 
    // a newline.
 
    fn consume_whitespace(&self, source: &mut InputSource) -> bool {
 
        debug_assert!(is_whitespace(source.next().unwrap()));
 

	
 
        let mut has_newline = false;
 
        while let Some(c) = source.next() {
 
            if !is_whitespace(c) {
 
                break;
 
            }
 

	
 
            if c == b'\n' {
 
                has_newline = true;
 
            }
 
            source.consume();
 
        }
 

	
 
        has_newline
 
    }
 

	
 
    fn emit_marker(&mut self, target: &mut TokenBuffer, kind: TokenMarkerKind, first_token: u32) {
 
        debug_assert!(
 
            target.markers
 
                .last().map(|v| v.first_token < first_token)
 
                .unwrap_or(true)
 
        );
 

	
 
        target.markers.push(TokenMarker{
 
            kind,
 
            curly_depth: self.curly_stack.len() as u32,
 
            first_token,
 
            last_token: u32::MAX,
 
            handled: false,
 
        });
 
    }
 

	
 
    fn check_ascii(&self, source: &InputSource) -> Result<(), ParseError> {
 
        match source.next() {
 
            Some(c) if !c.is_ascii() => {
 
                Err(ParseError::new_error_str_at_pos(source, source.pos(), "encountered a non-ASCII character"))
 
            },
 
            _else => {
 
                Ok(())
 
            },
 
        }
 
    }
 
}
 

	
 
// Helpers for characters
 
fn demarks_symbol(ident: &[u8]) -> bool {
 
    return
 
        ident == KW_STRUCT ||
 
            ident == KW_ENUM ||
 
            ident == KW_UNION ||
 
            ident == KW_FUNCTION ||
 
            ident == KW_PRIMITIVE ||
 
            ident == KW_COMPOSITE
 
}
 

	
 
#[inline]
 
fn demarks_import(ident: &[u8]) -> bool {
 
    return ident == KW_IMPORT;
 
}
 

	
 
#[inline]
 
fn is_whitespace(c: u8) -> bool {
 
    c.is_ascii_whitespace()
 
}
 

	
 
#[inline]
 
fn is_char_literal_start(c: u8) -> bool {
 
    return c == b'\'';
 
}
 

	
 
#[inline]
 
fn is_bytestring_literal_start(c: u8, source: &InputSource) -> bool {
 
    return c == b'b' && source.lookahead(1) == Some(b'"');
 
}
 

	
 
#[inline]
 
fn is_string_literal_start(c: u8) -> bool {
 
    return c == b'"';
 
}
 

	
 
#[inline]
 
fn is_pragma_start_or_pound(c: u8) -> bool {
 
    return c == b'#';
 
}
 

	
 
fn is_identifier_start(c: u8) -> bool {
 
    return
 
        (c >= b'a' && c <= b'z') ||
 
            (c >= b'A' && c <= b'Z') ||
 
            c == b'_'
 
}
 

	
 
fn is_identifier_remaining(c: u8) -> bool {
 
    return
 
        (c >= b'0' && c <= b'9') ||
 
            (c >= b'a' && c <= b'z') ||
 
            (c >= b'A' && c <= b'Z') ||
 
            c == b'_'
 
}
 

	
 
#[inline]
 
fn is_integer_literal_start(c: u8) -> bool {
 
    return c >= b'0' && c <= b'9';
 
}
 

	
 
fn maybe_number_remaining(c: u8) -> bool {
 
    // Note: hex range includes the possible binary indicator 'b' and 'B';
 
    return
 
        (c == b'o' || c == b'O' || c == b'x' || c == b'X') ||
 
            (c >= b'0' && c <= b'9') || (c >= b'A' && c <= b'F') || (c >= b'a' && c <= b'f') ||
 
            c == b'_';
 
}
src/protocol/parser/pass_typing.rs
Show inline comments
 
/// pass_typing
 
///
 
/// Performs type inference and type checking. Type inference is implemented by
 
/// applying constraints on (sub)trees of types. During this process the
 
/// resolver takes the `ParserType` structs (the representation of the types
 
/// written by the programmer), converts them to `InferenceType` structs (the
 
/// temporary data structure used during type inference) and attempts to arrive
 
/// at `ConcreteType` structs (the representation of a fully checked and
 
/// validated type).
 
///
 
/// The resolver will visit every statement and expression relevant to the
 
/// procedure and insert and determine its initial type based on context (e.g. a
 
/// return statement's expression must match the function's return type, an
 
/// if statement's test expression must evaluate to a boolean). When all are
 
/// visited we attempt to make progress in evaluating the types. Whenever a type
 
/// is progressed we queue the related expressions for further type progression.
 
/// Once no more expressions are in the queue the algorithm is finished. At this
 
/// point either all types are inferred (or can be trivially implicitly
 
/// determined), or we have incomplete types. In the latter case we return an
 
/// error.
 
///
 
/// TODO: Needs a thorough rewrite:
 
///  0. polymorph_progress is intentionally broken at the moment. Make it work
 
///     again and use a normal VecSomething.
 
///  1. The foundation for doing all of the work with predetermined indices
 
///     instead of with HashMaps is there, but it is not really used because of
 
///     time constraints. When time is available, rewrite the system such that
 
///     AST IDs are not needed, and only indices into arrays are used.
 
///  2. Remove the `msg` type?
 
///  3. Disallow certain types in certain operations (e.g. `Void`).
 

	
 
macro_rules! debug_log_enabled {
 
    () => { false };
 
}
 

	
 
macro_rules! debug_log {
 
    ($format:literal) => {
 
        enabled_debug_print!(false, "types", $format);
 
    };
 
    ($format:literal, $($args:expr),*) => {
 
        enabled_debug_print!(false, "types", $format, $($args),*);
 
    };
 
}
 

	
 
use std::collections::VecDeque;
 

	
 
use crate::collections::{ScopedBuffer, ScopedSection, DequeSet};
 
use crate::protocol::ast::*;
 
use crate::protocol::input_source::ParseError;
 
use crate::protocol::parser::ModuleCompilationPhase;
 
use crate::protocol::parser::type_table::*;
 
use crate::protocol::parser::token_parsing::*;
 
use super::visitor::{
 
    BUFFER_INIT_CAP_LARGE,
 
    BUFFER_INIT_CAP_SMALL,
 
    Ctx,
 
};
 

	
 
// -----------------------------------------------------------------------------
 
// Inference type
 
// -----------------------------------------------------------------------------
 

	
 
const VOID_TEMPLATE: [InferenceTypePart; 1] = [ InferenceTypePart::Void ];
 
const MESSAGE_TEMPLATE: [InferenceTypePart; 2] = [ InferenceTypePart::Message, InferenceTypePart::UInt8 ];
 
const BOOL_TEMPLATE: [InferenceTypePart; 1] = [ InferenceTypePart::Bool ];
 
const CHARACTER_TEMPLATE: [InferenceTypePart; 1] = [ InferenceTypePart::Character ];
 
const BYTEARRAY_TEMPLATE: [InferenceTypePart; 2] = [ InferenceTypePart::Array, InferenceTypePart::UInt8 ];
 
const STRING_TEMPLATE: [InferenceTypePart; 2] = [ InferenceTypePart::String, InferenceTypePart::Character ];
 
const NUMBERLIKE_TEMPLATE: [InferenceTypePart; 1] = [ InferenceTypePart::NumberLike ];
 
const INTEGERLIKE_TEMPLATE: [InferenceTypePart; 1] = [ InferenceTypePart::IntegerLike ];
 
const ARRAY_TEMPLATE: [InferenceTypePart; 2] = [ InferenceTypePart::Array, InferenceTypePart::Unknown ];
 
const SLICE_TEMPLATE: [InferenceTypePart; 2] = [ InferenceTypePart::Slice, InferenceTypePart::Unknown ];
 
const ARRAYLIKE_TEMPLATE: [InferenceTypePart; 2] = [ InferenceTypePart::ArrayLike, InferenceTypePart::Unknown ];
 

	
 
/// TODO: @performance Turn into PartialOrd+Ord to simplify checks
 
#[derive(Debug, Clone, Eq, PartialEq)]
 
pub(crate) enum InferenceTypePart {
 
    // When we infer types of AST elements that support polymorphic arguments,
 
    // then we might have the case that multiple embedded types depend on the
 
    // polymorphic type (e.g. func bla(T a, T[] b) -> T[][]). If we can infer
 
    // the type in one place (e.g. argument a), then we may propagate this
 
    // information to other types (e.g. argument b and the return type). For
 
    // this reason we place markers in the `InferenceType` instances such that
 
    // we know which part of the type was originally a polymorphic argument.
 
    Marker(u32),
 
    // Completely unknown type, needs to be inferred
 
    Unknown,
 
    // Partially known type, may be inferred to to be the appropriate related 
 
    // type.
 
    // IndexLike,      // index into array/slice
 
    NumberLike,     // any kind of integer/float
 
    IntegerLike,    // any kind of integer
 
    ArrayLike,      // array or slice. Note that this must have a subtype
 
    PortLike,       // input or output port
 
    // Special types that cannot be instantiated by the user
 
    Void, // For builtin functions that do not return anything
 
    // Concrete types without subtypes
 
    Bool,
 
    UInt8,
 
    UInt16,
 
    UInt32,
 
    UInt64,
 
    SInt8,
 
    SInt16,
 
    SInt32,
 
    SInt64,
 
    Character,
 
    String,
 
    // One subtype
 
    Message,
 
    Array,
 
    Slice,
 
    Input,
 
    Output,
 
    // Tuple with any number of subtypes (for practical reasons 1 element is impossible)
 
    Tuple(u32),
 
    // A user-defined type with any number of subtypes
 
    Instance(DefinitionId, u32)
 
}
 

	
 
impl InferenceTypePart {
 
    fn is_marker(&self) -> bool {
 
        match self {
 
            InferenceTypePart::Marker(_) => true,
 
            _ => false,
 
        }
 
    }
 

	
 
    /// Checks if the type is concrete, markers are interpreted as concrete
 
    /// types.
 
    fn is_concrete(&self) -> bool {
 
        use InferenceTypePart as ITP;
 
        match self {
 
            ITP::Unknown | ITP::NumberLike |
 
            ITP::IntegerLike | ITP::ArrayLike | ITP::PortLike => false,
 
            _ => true
 
        }
 
    }
 

	
 
    fn is_concrete_number(&self) -> bool {
 
        use InferenceTypePart as ITP;
 
        match self {
 
            ITP::UInt8 | ITP::UInt16 | ITP::UInt32 | ITP::UInt64 |
 
            ITP::SInt8 | ITP::SInt16 | ITP::SInt32 | ITP::SInt64 => true,
 
            _ => false,
 
        }
 
    }
 

	
 
    fn is_concrete_integer(&self) -> bool {
 
        use InferenceTypePart as ITP;
 
        match self {
 
            ITP::UInt8 | ITP::UInt16 | ITP::UInt32 | ITP::UInt64 |
 
            ITP::SInt8 | ITP::SInt16 | ITP::SInt32 | ITP::SInt64 => true,
 
            _ => false,
 
        }
 
    }
 

	
 
    fn is_concrete_arraylike(&self) -> bool {
 
        use InferenceTypePart as ITP;
 
        match self {
 
            ITP::Array | ITP::Slice | ITP::String | ITP::Message => true,
 
            _ => false,
 
        }
 
    }
 

	
 
    fn is_concrete_port(&self) -> bool {
 
        use InferenceTypePart as ITP;
 
        match self {
 
            ITP::Input | ITP::Output => true,
 
            _ => false,
 
        }
 
    }
 

	
 
    /// Checks if a part is less specific than the argument. Only checks for 
 
    /// single-part inference (i.e. not the replacement of an `Unknown` variant 
 
    /// with the argument)
 
    fn may_be_inferred_from(&self, arg: &InferenceTypePart) -> bool {
 
        use InferenceTypePart as ITP;
 

	
 
        (*self == ITP::IntegerLike && arg.is_concrete_integer()) ||
 
        (*self == ITP::NumberLike && (arg.is_concrete_number() || *arg == ITP::IntegerLike)) ||
 
        (*self == ITP::ArrayLike && arg.is_concrete_arraylike()) ||
 
        (*self == ITP::PortLike && arg.is_concrete_port())
 
    }
 

	
 
    /// Checks if a part is more specific
 

	
 
    /// Returns the change in "iteration depth" when traversing this particular
 
    /// part. The iteration depth is used to traverse the tree in a linear 
 
    /// fashion. It is basically `number_of_subtypes - 1`
 
    fn depth_change(&self) -> i32 {
 
        use InferenceTypePart as ITP;
 
        match &self {
 
            ITP::Unknown | ITP::NumberLike | ITP::IntegerLike |
 
            ITP::Void | ITP::Bool |
 
            ITP::UInt8 | ITP::UInt16 | ITP::UInt32 | ITP::UInt64 |
 
            ITP::SInt8 | ITP::SInt16 | ITP::SInt32 | ITP::SInt64 |
 
            ITP::Character => {
 
                -1
 
            },
 
            ITP::Marker(_) |
 
            ITP::ArrayLike | ITP::Message | ITP::Array | ITP::Slice |
 
            ITP::PortLike | ITP::Input | ITP::Output | ITP::String => {
 
                // One subtype, so do not modify depth
 
                0
 
            },
 
            ITP::Tuple(num) | ITP::Instance(_, num) => {
 
                (*num as i32) - 1
 
            }
 
        }
 
    }
 
}
 

	
 
#[derive(Debug, Clone)]
 
struct InferenceType {
 
    has_marker: bool,
 
    is_done: bool,
 
    parts: Vec<InferenceTypePart>,
 
}
 

	
 
impl InferenceType {
 
    /// Generates a new InferenceType. The two boolean flags will be checked in
 
    /// debug mode.
 
    fn new(has_marker: bool, is_done: bool, parts: Vec<InferenceTypePart>) -> Self {
 
        dbg_code!({
 
            debug_assert!(!parts.is_empty());
 
            let parts_body_marker = parts.iter().any(|v| v.is_marker());
 
            debug_assert_eq!(has_marker, parts_body_marker);
 
            let parts_done = parts.iter().all(|v| v.is_concrete());
 
            debug_assert_eq!(is_done, parts_done, "{:?}", parts);
 
        });
 
        Self{ has_marker, is_done, parts }
 
    }
 

	
 
    /// Replaces a type subtree with the provided subtree. The caller must make
 
    /// sure the the replacement is a well formed type subtree.
 
    fn replace_subtree(&mut self, start_idx: usize, with: &[InferenceTypePart]) {
 
        let end_idx = Self::find_subtree_end_idx(&self.parts, start_idx);
 
        debug_assert_eq!(with.len(), Self::find_subtree_end_idx(with, 0));
 
        self.parts.splice(start_idx..end_idx, with.iter().cloned());
 
        self.recompute_is_done();
 
    }
 

	
 
    // TODO: @performance, might all be done inline in the type inference methods
 
    fn recompute_is_done(&mut self) {
 
        self.is_done = self.parts.iter().all(|v| v.is_concrete());
 
    }
 

	
 
    /// Seeks a body marker starting at the specified position. If a marker is
 
    /// found then its value and the index of the type subtree that follows it
 
    /// is returned.
 
    fn find_marker(&self, mut start_idx: usize) -> Option<(u32, usize)> {
 
        while start_idx < self.parts.len() {
 
            if let InferenceTypePart::Marker(marker) = &self.parts[start_idx] {
 
                return Some((*marker, start_idx + 1))
 
            }
 

	
 
            start_idx += 1;
 
        }
 
@@ -1537,842 +1538,853 @@ impl PassTyping {
 
        let upcast_id = id.upcast();
 
        let self_index = self.insert_initial_inference_node(ctx, upcast_id)?;
 

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

	
 
        let old_parent = self.parent_index.replace(self_index);
 
        let left_index = self.visit_expr(ctx, lhs_expr_id)?;
 
        let right_index = self.visit_expr(ctx, rhs_expr_id)?;
 

	
 
        let inference_rule = match binary_op {
 
            BO::Concatenate =>
 
                InferenceRule::Concatenate(InferenceRuleTwoArgs{
 
                    argument1_index: left_index,
 
                    argument2_index: right_index,
 
                }),
 
            BO::LogicalAnd | BO::LogicalOr =>
 
                InferenceRule::TriEqualAll(InferenceRuleTriEqualAll{
 
                    template: InferenceRuleTemplate::new_forced(&BOOL_TEMPLATE),
 
                    argument1_index: left_index,
 
                    argument2_index: right_index,
 
                }),
 
            BO::BitwiseOr | BO::BitwiseXor | BO::BitwiseAnd | BO::Remainder | BO::ShiftLeft | BO::ShiftRight =>
 
                InferenceRule::TriEqualAll(InferenceRuleTriEqualAll{
 
                    template: InferenceRuleTemplate::new_template(&INTEGERLIKE_TEMPLATE),
 
                    argument1_index: left_index,
 
                    argument2_index: right_index,
 
                }),
 
            BO::Equality | BO::Inequality =>
 
                InferenceRule::TriEqualArgs(InferenceRuleTriEqualArgs{
 
                    argument_template: InferenceRuleTemplate::new_none(),
 
                    result_template: InferenceRuleTemplate::new_forced(&BOOL_TEMPLATE),
 
                    argument1_index: left_index,
 
                    argument2_index: right_index,
 
                }),
 
            BO::LessThan | BO::GreaterThan | BO::LessThanEqual | BO::GreaterThanEqual =>
 
                InferenceRule::TriEqualArgs(InferenceRuleTriEqualArgs{
 
                    argument_template: InferenceRuleTemplate::new_template(&NUMBERLIKE_TEMPLATE),
 
                    result_template: InferenceRuleTemplate::new_forced(&BOOL_TEMPLATE),
 
                    argument1_index: left_index,
 
                    argument2_index: right_index,
 
                }),
 
            BO::Add | BO::Subtract | BO::Multiply | BO::Divide =>
 
                InferenceRule::TriEqualAll(InferenceRuleTriEqualAll{
 
                    template: InferenceRuleTemplate::new_template(&NUMBERLIKE_TEMPLATE),
 
                    argument1_index: left_index,
 
                    argument2_index: right_index,
 
                }),
 
        };
 

	
 
        let node = &mut self.infer_nodes[self_index];
 
        node.inference_rule = inference_rule;
 

	
 
        self.parent_index = old_parent;
 
        self.progress_inference_rule(ctx, self_index)?;
 
        return Ok(self_index);
 
    }
 

	
 
    fn visit_unary_expr(&mut self, ctx: &mut Ctx, id: UnaryExpressionId) -> VisitExprResult {
 
        use UnaryOperator as UO;
 

	
 
        let upcast_id = id.upcast();
 
        let self_index = self.insert_initial_inference_node(ctx, upcast_id)?;
 

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

	
 
        let old_parent = self.parent_index.replace(self_index);
 
        let argument_index = self.visit_expr(ctx, arg_expr_id)?;
 

	
 
        let template = match operation {
 
            UO::Positive | UO::Negative =>
 
                InferenceRuleTemplate::new_template(&NUMBERLIKE_TEMPLATE),
 
            UO::BitwiseNot =>
 
                InferenceRuleTemplate::new_template(&INTEGERLIKE_TEMPLATE),
 
            UO::LogicalNot =>
 
                InferenceRuleTemplate::new_forced(&BOOL_TEMPLATE),
 
        };
 

	
 
        let node = &mut self.infer_nodes[self_index];
 
        node.inference_rule = InferenceRule::BiEqual(InferenceRuleBiEqual{
 
            template, argument_index,
 
        });
 

	
 
        self.parent_index = old_parent;
 
        self.progress_inference_rule_bi_equal(ctx, self_index)?;
 
        return Ok(self_index);
 
    }
 

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

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

	
 
        let old_parent = self.parent_index.replace(self_index);
 
        let subject_index = self.visit_expr(ctx, subject_expr_id)?;
 
        let index_index = self.visit_expr(ctx, index_expr_id)?; // cool name, bro
 

	
 
        let node = &mut self.infer_nodes[self_index];
 
        node.inference_rule = InferenceRule::IndexingExpr(InferenceRuleIndexingExpr{
 
            subject_index, index_index,
 
        });
 

	
 
        self.parent_index = old_parent;
 
        self.progress_inference_rule_indexing_expr(ctx, self_index)?;
 
        return Ok(self_index);
 
    }
 

	
 
    fn visit_slicing_expr(&mut self, ctx: &mut Ctx, id: SlicingExpressionId) -> VisitExprResult {
 
        let upcast_id = id.upcast();
 
        let self_index = self.insert_initial_inference_node(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;
 

	
 
        let old_parent = self.parent_index.replace(self_index);
 
        let subject_index = self.visit_expr(ctx, subject_expr_id)?;
 
        let from_index = self.visit_expr(ctx, from_expr_id)?;
 
        let to_index = self.visit_expr(ctx, to_expr_id)?;
 

	
 
        let node = &mut self.infer_nodes[self_index];
 
        node.inference_rule = InferenceRule::SlicingExpr(InferenceRuleSlicingExpr{
 
            subject_index, from_index, to_index,
 
        });
 

	
 
        self.parent_index = old_parent;
 
        self.progress_inference_rule_slicing_expr(ctx, self_index)?;
 
        return Ok(self_index);
 
    }
 

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

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

	
 
        let old_parent = self.parent_index.replace(self_index);
 
        let subject_index = self.visit_expr(ctx, subject_expr_id)?;
 

	
 
        let node = &mut self.infer_nodes[self_index];
 
        let inference_rule = match &ctx.heap[id].kind {
 
            SelectKind::StructField(field_identifier) =>
 
                InferenceRule::SelectStructField(InferenceRuleSelectStructField{
 
                    subject_index,
 
                    selected_field: field_identifier.clone(),
 
                }),
 
            SelectKind::TupleMember(member_index) =>
 
                InferenceRule::SelectTupleMember(InferenceRuleSelectTupleMember{
 
                    subject_index,
 
                    selected_index: *member_index,
 
                }),
 
        };
 
        node.inference_rule = inference_rule;
 

	
 
        self.parent_index = old_parent;
 
        self.progress_inference_rule(ctx, self_index)?;
 
        return Ok(self_index);
 
    }
 

	
 
    fn visit_literal_expr(&mut self, ctx: &mut Ctx, id: LiteralExpressionId) -> VisitExprResult {
 
        let upcast_id = id.upcast();
 
        let self_index = self.insert_initial_inference_node(ctx, upcast_id)?;
 

	
 
        let old_parent = self.parent_index.replace(self_index);
 

	
 
        let literal_expr = &ctx.heap[id];
 
        match &literal_expr.value {
 
            Literal::Null => {
 
                let node = &mut self.infer_nodes[self_index];
 
                node.inference_rule = InferenceRule::MonoTemplate(InferenceRuleTemplate::new_template(&MESSAGE_TEMPLATE));
 
            },
 
            Literal::Integer(_) => {
 
                let node = &mut self.infer_nodes[self_index];
 
                node.inference_rule = InferenceRule::MonoTemplate(InferenceRuleTemplate::new_template(&INTEGERLIKE_TEMPLATE));
 
            },
 
            Literal::True | Literal::False => {
 
                let node = &mut self.infer_nodes[self_index];
 
                node.inference_rule = InferenceRule::MonoTemplate(InferenceRuleTemplate::new_forced(&BOOL_TEMPLATE));
 
            },
 
            Literal::Character(_) => {
 
                let node = &mut self.infer_nodes[self_index];
 
                node.inference_rule = InferenceRule::MonoTemplate(InferenceRuleTemplate::new_forced(&CHARACTER_TEMPLATE));
 
            },
 
            Literal::Bytestring(_) => {
 
                let node = &mut self.infer_nodes[self_index];
 
                node.inference_rule = InferenceRule::MonoTemplate(InferenceRuleTemplate::new_forced(&BYTEARRAY_TEMPLATE));
 
            },
 
            Literal::String(_) => {
 
                let node = &mut self.infer_nodes[self_index];
 
                node.inference_rule = InferenceRule::MonoTemplate(InferenceRuleTemplate::new_forced(&STRING_TEMPLATE));
 
            },
 
            Literal::Struct(literal) => {
 
                // Visit field expressions
 
                let mut expr_ids = self.expr_buffer.start_section();
 
                for field in &literal.fields {
 
                    expr_ids.push(field.value);
 
                }
 

	
 
                let mut expr_indices = self.index_buffer.start_section();
 
                for expr_id in expr_ids.iter_copied() {
 
                    let expr_index = self.visit_expr(ctx, expr_id)?;
 
                    expr_indices.push(expr_index);
 
                }
 
                expr_ids.forget();
 
                let element_indices = expr_indices.into_vec();
 

	
 
                // Assign rule and extra data index to inference node
 
                let poly_data_index = self.insert_initial_struct_polymorph_data(ctx, id);
 
                let node = &mut self.infer_nodes[self_index];
 
                node.poly_data_index = poly_data_index;
 
                node.inference_rule = InferenceRule::LiteralStruct(InferenceRuleLiteralStruct{
 
                    element_indices,
 
                });
 
            },
 
            Literal::Enum(_) => {
 
                // Enumerations do not carry any subexpressions, but may still
 
                // have a user-defined polymorphic marker variable. For this 
 
                // reason we may still have to apply inference to this 
 
                // polymorphic variable
 
                let poly_data_index = self.insert_initial_enum_polymorph_data(ctx, id);
 
                let node = &mut self.infer_nodes[self_index];
 
                node.poly_data_index = poly_data_index;
 
                node.inference_rule = InferenceRule::LiteralEnum;
 
            },
 
            Literal::Union(literal) => {
 
                // May carry subexpressions and polymorphic arguments
 
                let expr_ids = self.expr_buffer.start_section_initialized(literal.values.as_slice());
 
                let poly_data_index = self.insert_initial_union_polymorph_data(ctx, id);
 

	
 
                let mut expr_indices = self.index_buffer.start_section();
 
                for expr_id in expr_ids.iter_copied() {
 
                    let expr_index = self.visit_expr(ctx, expr_id)?;
 
                    expr_indices.push(expr_index);
 
                }
 
                expr_ids.forget();
 
                let element_indices = expr_indices.into_vec();
 

	
 
                let node = &mut self.infer_nodes[self_index];
 
                node.poly_data_index = poly_data_index;
 
                node.inference_rule = InferenceRule::LiteralUnion(InferenceRuleLiteralUnion{
 
                    element_indices,
 
                });
 
            },
 
            Literal::Array(expressions) => {
 
                let expr_ids = self.expr_buffer.start_section_initialized(expressions.as_slice());
 

	
 
                let mut expr_indices = self.index_buffer.start_section();
 
                for expr_id in expr_ids.iter_copied() {
 
                    let expr_index = self.visit_expr(ctx, expr_id)?;
 
                    expr_indices.push(expr_index);
 
                }
 
                expr_ids.forget();
 
                let element_indices = expr_indices.into_vec();
 

	
 
                let node = &mut self.infer_nodes[self_index];
 
                node.inference_rule = InferenceRule::LiteralArray(InferenceRuleLiteralArray{
 
                    element_indices,
 
                });
 
            },
 
            Literal::Tuple(expressions) => {
 
                let expr_ids = self.expr_buffer.start_section_initialized(expressions.as_slice());
 

	
 
                let mut expr_indices = self.index_buffer.start_section();
 
                for expr_id in expr_ids.iter_copied() {
 
                    let expr_index = self.visit_expr(ctx, expr_id)?;
 
                    expr_indices.push(expr_index);
 
                }
 
                expr_ids.forget();
 
                let element_indices = expr_indices.into_vec();
 

	
 
                let node = &mut self.infer_nodes[self_index];
 
                node.inference_rule = InferenceRule::LiteralTuple(InferenceRuleLiteralTuple{
 
                    element_indices,
 
                })
 
            }
 
        }
 

	
 
        self.parent_index = old_parent;
 
        self.progress_inference_rule(ctx, self_index)?;
 
        return Ok(self_index);
 
    }
 

	
 
    fn visit_cast_expr(&mut self, ctx: &mut Ctx, id: CastExpressionId) -> VisitExprResult {
 
        let upcast_id = id.upcast();
 
        let self_index = self.insert_initial_inference_node(ctx, upcast_id)?;
 

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

	
 
        let old_parent = self.parent_index.replace(self_index);
 
        let subject_index = self.visit_expr(ctx, subject_expr_id)?;
 

	
 
        let node = &mut self.infer_nodes[self_index];
 
        node.inference_rule = InferenceRule::CastExpr(InferenceRuleCastExpr{
 
            subject_index,
 
        });
 

	
 
        self.parent_index = old_parent;
 

	
 
        // The cast expression is a bit special at this point: the progression
 
        // function simply makes sure input/output types are compatible. But if
 
        // the programmer explicitly specified the output type, then we can
 
        // already perform that inference rule here.
 
        {
 
            let cast_expr = &ctx.heap[id];
 
            let specified_type = self.determine_inference_type_from_parser_type_elements(&cast_expr.to_type.elements, true);
 
            let _progress = self.apply_template_constraint(ctx, self_index, &specified_type.parts)?;
 
        }
 

	
 
        self.progress_inference_rule_cast_expr(ctx, self_index)?;
 
        return Ok(self_index);
 
    }
 

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

	
 
        // By default we set the polymorph idx for calls to 0. If the call
 
        // refers to a non-polymorphic function, then it will be "monomorphed"
 
        // once, hence we end up pointing to the correct instance.
 
        self.infer_nodes[self_index].field_index = 0;
 

	
 
        // Visit all arguments
 
        let old_parent = self.parent_index.replace(self_index);
 

	
 
        let call_expr = &ctx.heap[id];
 
        let expr_ids = self.expr_buffer.start_section_initialized(call_expr.arguments.as_slice());
 
        let mut expr_indices = self.index_buffer.start_section();
 

	
 
        for arg_expr_id in expr_ids.iter_copied() {
 
            let expr_index = self.visit_expr(ctx, arg_expr_id)?;
 
            expr_indices.push(expr_index);
 
        }
 
        expr_ids.forget();
 
        let argument_indices = expr_indices.into_vec();
 

	
 

	
 
        let node = &mut self.infer_nodes[self_index];
 
        node.poly_data_index = extra_index;
 
        node.inference_rule = InferenceRule::CallExpr(InferenceRuleCallExpr{
 
            argument_indices,
 
        });
 

	
 
        self.parent_index = old_parent;
 
        self.progress_inference_rule_call_expr(ctx, self_index)?;
 
        return Ok(self_index);
 
    }
 

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

	
 
        let var_expr = &ctx.heap[id];
 
        debug_assert!(var_expr.declaration.is_some());
 
        let old_parent = self.parent_index.replace(self_index);
 

	
 
        let declaration = &ctx.heap[var_expr.declaration.unwrap()];
 
        let mut var_data_index = None;
 
        for (index, var_data) in self.var_data.iter().enumerate() {
 
            if var_data.var_id == declaration.this {
 
                var_data_index = Some(index);
 
                break;
 
            }
 
        }
 

	
 
        let var_data_index = if let Some(var_data_index) = var_data_index {
 
            let var_data = &mut self.var_data[var_data_index];
 
            var_data.used_at.push(self_index);
 

	
 
            var_data_index
 
        } else {
 
            // If we're in a binding expression then it might the first time we
 
            // encounter the variable, so add a `VarData` entry.
 
            debug_assert_eq!(declaration.kind, VariableKind::Binding);
 
            let var_type = self.determine_inference_type_from_parser_type_elements(
 
                &declaration.parser_type.elements, true
 
            );
 
            let var_data_index = self.var_data.len();
 
            self.var_data.push(VarData{
 
                var_id: declaration.this,
 
                var_type,
 
                used_at: vec![self_index],
 
                linked_var: None,
 
            });
 

	
 
            var_data_index
 
        };
 

	
 
        let node = &mut self.infer_nodes[self_index];
 
        node.inference_rule = InferenceRule::VariableExpr(InferenceRuleVariableExpr{
 
            var_data_index,
 
        });
 

	
 
        self.parent_index = old_parent;
 
        self.progress_inference_rule_variable_expr(ctx, self_index)?;
 
        return Ok(self_index);
 
    }
 
}
 

	
 
// -----------------------------------------------------------------------------
 
// PassTyping - Type-inference progression
 
// -----------------------------------------------------------------------------
 

	
 
impl PassTyping {
 
    #[allow(dead_code)] // used when debug flag at the top of this file is true.
 
    fn debug_get_display_name(&self, ctx: &Ctx, node_index: InferNodeIndex) -> String {
 
        let expr_type = &self.infer_nodes[node_index].expr_type;
 
        expr_type.display_name(&ctx.heap)
 
    }
 

	
 
    fn resolve_types(&mut self, ctx: &mut Ctx, queue: &mut ResolveQueue) -> Result<(), ParseError> {
 
        // Keep inferring until we can no longer make any progress
 
        while !self.node_queued.is_empty() {
 
            while !self.node_queued.is_empty() {
 
                let node_index = self.node_queued.pop_front().unwrap();
 
                self.progress_inference_rule(ctx, node_index)?;
 
            }
 

	
 
            // Nothing is queued anymore. However we might have integer literals
 
            // whose type cannot be inferred. For convenience's sake we'll
 
            // infer these to be s32.
 
            for (infer_node_index, infer_node) in self.infer_nodes.iter_mut().enumerate() {
 
                let expr_type = &mut infer_node.expr_type;
 
                if !expr_type.is_done && expr_type.parts.len() == 1 && expr_type.parts[0] == InferenceTypePart::IntegerLike {
 
                    // Force integer type to s32
 
                    expr_type.parts[0] = InferenceTypePart::SInt32;
 
                    expr_type.is_done = true;
 

	
 
                    // Requeue expression (and its parent, if it exists)
 
                    self.node_queued.push_back(infer_node_index);
 
                    if let Some(node_parent_index) = infer_node.parent_index {
 
                        self.node_queued.push_back(node_parent_index);
 
                    }
 
                }
 
            }
 
        }
 

	
 
        // Helper for transferring polymorphic variables to concrete types and
 
        // checking if they're completely specified
 
        fn poly_data_type_to_concrete_type(
 
            ctx: &Ctx, expr_id: ExpressionId, inference_poly_args: &Vec<InferenceType>,
 
            first_concrete_part: ConcreteTypePart,
 
        ) -> Result<ConcreteType, ParseError> {
 
            // Prepare storage vector
 
            let mut num_inference_parts = 0;
 
            for inference_type in inference_poly_args {
 
                num_inference_parts += inference_type.parts.len();
 
            }
 

	
 
            let mut concrete_type = ConcreteType{
 
                parts: Vec::with_capacity(1 + num_inference_parts),
 
            };
 
            concrete_type.parts.push(first_concrete_part);
 

	
 
            // Go through all polymorphic arguments and add them to the concrete
 
            // types.
 
            for (poly_idx, poly_type) in inference_poly_args.iter().enumerate() {
 
                if !poly_type.is_done {
 
                    let expr = &ctx.heap[expr_id];
 
                    let definition = match expr {
 
                        Expression::Call(expr) => expr.procedure.upcast(),
 
                        Expression::Literal(expr) => match &expr.value {
 
                            Literal::Enum(lit) => lit.definition,
 
                            Literal::Union(lit) => lit.definition,
 
                            Literal::Struct(lit) => lit.definition,
 
                            _ => unreachable!()
 
                        },
 
                        _ => unreachable!(),
 
                    };
 
                    let poly_vars = ctx.heap[definition].poly_vars();
 
                    return Err(ParseError::new_error_at_span(
 
                        &ctx.module().source, expr.operation_span(), format!(
 
                            "could not fully infer the type of polymorphic variable '{}' of this expression (got '{}')",
 
                            poly_vars[poly_idx].value.as_str(), poly_type.display_name(&ctx.heap)
 
                        )
 
                    ));
 
                }
 

	
 
                poly_type.write_concrete_type(&mut concrete_type);
 
            }
 

	
 
            Ok(concrete_type)
 
        }
 

	
 
        // Every expression checked, and new monomorphs are queued. Transfer the
 
        // expression information to the AST. If this is the first time we're
 
        // visiting this procedure then we assign expression indices as well.
 
        let procedure = &ctx.heap[self.procedure_id];
 
        let num_infer_nodes = self.infer_nodes.len();
 
        let mut monomorph = ProcedureDefinitionMonomorph{
 
            argument_types: Vec::with_capacity(procedure.parameters.len()),
 
            expr_info: Vec::with_capacity(num_infer_nodes),
 
        };
 

	
 
        // For all of the expressions look up the TypeId (or create a new one).
 
        // For function calls and component instantiations figure out if they
 
        // need to be typechecked
 
        for infer_node in self.infer_nodes.iter_mut() {
 
            // Determine type ID
 
            let expr = &ctx.heap[infer_node.expr_id];
 

	
 
            // TODO: Maybe optimize? Split insertion up into lookup, then clone
 
            //  if needed?
 
            let mut concrete_type = ConcreteType::default();
 
            infer_node.expr_type.write_concrete_type(&mut concrete_type);
 
            let info_type_id = ctx.types.add_monomorphed_type(ctx.modules, ctx.heap, ctx.arch, concrete_type)?;
 

	
 
            // Determine procedure type ID, i.e. a called/instantiated
 
            // procedure's signature.
 
            let info_variant = if let Expression::Call(expr) = expr {
 
                // Construct full function type. If not yet typechecked then
 
                // queue it for typechecking.
 
                let poly_data = &self.poly_data[infer_node.poly_data_index as usize];
 
                debug_assert!(expr.method.is_user_defined() || expr.method.is_public_builtin());
 
                let procedure_id = expr.procedure;
 
                let num_poly_vars = poly_data.poly_vars.len() as u32;
 

	
 
                let first_part = match expr.method {
 
                    Method::UserFunction => ConcreteTypePart::Function(procedure_id, num_poly_vars),
 
                    Method::UserComponent => ConcreteTypePart::Component(procedure_id, num_poly_vars),
 
                    _ => ConcreteTypePart::Function(procedure_id, num_poly_vars),
 
                };
 

	
 

	
 
                let definition_id = procedure_id.upcast();
 
                let signature_type = poly_data_type_to_concrete_type(
 
                    ctx, infer_node.expr_id, &poly_data.poly_vars, first_part
 
                )?;
 

	
 
                let (type_id, monomorph_index) = if let Some(type_id) = ctx.types.get_monomorph_type_id(&definition_id, &signature_type.parts) {
 
                    // Procedure is already typechecked
 
                    let monomorph_index = ctx.types.get_monomorph(type_id).variant.as_procedure().monomorph_index;
 
                    (type_id, monomorph_index)
 
                } else {
 
                    // Procedure is not yet typechecked, reserve a TypeID and a monomorph index
 
                    let procedure_to_check = &mut ctx.heap[procedure_id];
 
                    let monomorph_index = procedure_to_check.monomorphs.len() as u32;
 
                    procedure_to_check.monomorphs.push(ProcedureDefinitionMonomorph::new_invalid());
 
                    let type_id = ctx.types.reserve_procedure_monomorph_type_id(&definition_id, signature_type, monomorph_index);
 

	
 
                    if !procedure_to_check.source.is_builtin() {
 
                        // Only perform typechecking on the user-defined
 
                        // procedures
 
                        queue.push_back(ResolveQueueElement{
 
                            root_id: ctx.heap[definition_id].defined_in(),
 
                            definition_id,
 
                            reserved_type_id: type_id,
 
                            reserved_monomorph_index: monomorph_index,
 
                        });
 
                    }
 

	
 
                    (type_id, monomorph_index)
 
                };
 

	
 
                ExpressionInfoVariant::Procedure(type_id, monomorph_index)
 
            } else if let Expression::Select(_expr) = expr {
 
                ExpressionInfoVariant::Select(infer_node.field_index)
 
            } else {
 
                ExpressionInfoVariant::Generic
 
            };
 

	
 
            infer_node.info_type_id = info_type_id;
 
            infer_node.info_variant = info_variant;
 
        }
 

	
 
        // Write the types of the arguments
 
        let procedure = &ctx.heap[self.procedure_id];
 
        for parameter_id in procedure.parameters.iter().copied() {
 
            let mut concrete = ConcreteType::default();
 
            let var_data = self.var_data.iter().find(|v| v.var_id == parameter_id).unwrap();
 
            var_data.var_type.write_concrete_type(&mut concrete);
 
            let type_id = ctx.types.add_monomorphed_type(ctx.modules, ctx.heap, ctx.arch, concrete)?;
 
            monomorph.argument_types.push(type_id)
 
        }
 

	
 
        // Determine if we have already assigned type indices to the expressions
 
        // before (the indices that, for a monomorph, can retrieve the type of
 
        // the expression).
 
        let has_type_indices = self.reserved_monomorph_index > 0;
 
        if has_type_indices {
 
            // already have indices, so resize and then index into it
 
            debug_assert!(monomorph.expr_info.is_empty());
 
            monomorph.expr_info.resize(num_infer_nodes, ExpressionInfo::new_invalid());
 
            for infer_node in self.infer_nodes.iter() {
 
                let type_index = ctx.heap[infer_node.expr_id].type_index();
 
                monomorph.expr_info[type_index as usize] = infer_node.as_expression_info();
 
            }
 
        } else {
 
            // no indices yet, need to be assigned in AST
 
            for infer_node in self.infer_nodes.iter() {
 
                let type_index = monomorph.expr_info.len();
 
                monomorph.expr_info.push(infer_node.as_expression_info());
 
                *ctx.heap[infer_node.expr_id].type_index_mut() = type_index as i32;
 
            }
 
        }
 

	
 
        // Push the information into the AST
 
        let procedure = &mut ctx.heap[self.procedure_id];
 
        procedure.monomorphs[self.reserved_monomorph_index as usize] = monomorph;
 

	
 
        Ok(())
 
    }
 

	
 
    fn progress_inference_rule(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        use InferenceRule as IR;
 

	
 
        let node = &self.infer_nodes[node_index];
 
        match &node.inference_rule {
 
        debug_log!("Progressing inference node (node_index: {})", node_index);
 
        debug_log!(" * Expression ID: {}", node.expr_id.index);
 
        debug_log!(" * Expression type pre : {}", node.expr_type.display_name(&ctx.heap));
 
        let result = match &node.inference_rule {
 
            IR::Noop =>
 
                unreachable!(),
 
            IR::MonoTemplate(_) =>
 
                self.progress_inference_rule_mono_template(ctx, node_index),
 
            IR::BiEqual(_) =>
 
                self.progress_inference_rule_bi_equal(ctx, node_index),
 
            IR::TriEqualArgs(_) =>
 
                self.progress_inference_rule_tri_equal_args(ctx, node_index),
 
            IR::TriEqualAll(_) =>
 
                self.progress_inference_rule_tri_equal_all(ctx, node_index),
 
            IR::Concatenate(_) =>
 
                self.progress_inference_rule_concatenate(ctx, node_index),
 
            IR::IndexingExpr(_) =>
 
                self.progress_inference_rule_indexing_expr(ctx, node_index),
 
            IR::SlicingExpr(_) =>
 
                self.progress_inference_rule_slicing_expr(ctx, node_index),
 
            IR::SelectStructField(_) =>
 
                self.progress_inference_rule_select_struct_field(ctx, node_index),
 
            IR::SelectTupleMember(_) =>
 
                self.progress_inference_rule_select_tuple_member(ctx, node_index),
 
            IR::LiteralStruct(_) =>
 
                self.progress_inference_rule_literal_struct(ctx, node_index),
 
            IR::LiteralEnum =>
 
                self.progress_inference_rule_literal_enum(ctx, node_index),
 
            IR::LiteralUnion(_) =>
 
                self.progress_inference_rule_literal_union(ctx, node_index),
 
            IR::LiteralArray(_) =>
 
                self.progress_inference_rule_literal_array(ctx, node_index),
 
            IR::LiteralTuple(_) =>
 
                self.progress_inference_rule_literal_tuple(ctx, node_index),
 
            IR::CastExpr(_) =>
 
                self.progress_inference_rule_cast_expr(ctx, node_index),
 
            IR::CallExpr(_) =>
 
                self.progress_inference_rule_call_expr(ctx, node_index),
 
            IR::VariableExpr(_) =>
 
                self.progress_inference_rule_variable_expr(ctx, node_index),
 
        }
 
        };
 

	
 
        debug_log!(" * Expression type post: {}", self.infer_nodes[node_index].expr_type.display_name(&ctx.heap));
 
        return result;
 
    }
 

	
 
    fn progress_inference_rule_mono_template(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let rule = *node.inference_rule.as_mono_template();
 

	
 
        let progress = self.progress_template(ctx, node_index, rule.application, rule.template)?;
 
        if progress { self.queue_node_parent(node_index); }
 

	
 
        return Ok(());
 
    }
 

	
 
    fn progress_inference_rule_bi_equal(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let rule = node.inference_rule.as_bi_equal();
 
        let template = rule.template;
 
        let arg_index = rule.argument_index;
 

	
 
        let base_progress = self.progress_template(ctx, node_index, template.application, template.template)?;
 
        let (node_progress, arg_progress) = self.apply_equal2_constraint(ctx, node_index, node_index, 0, arg_index, 0)?;
 

	
 
        if base_progress || node_progress { self.queue_node_parent(node_index); }
 
        if arg_progress { self.queue_node(arg_index); }
 

	
 
        return Ok(())
 
    }
 

	
 
    fn progress_inference_rule_tri_equal_args(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let rule = node.inference_rule.as_tri_equal_args();
 

	
 
        let result_template = rule.result_template;
 
        let argument_template = rule.argument_template;
 
        let arg1_index = rule.argument1_index;
 
        let arg2_index = rule.argument2_index;
 

	
 
        let self_template_progress = self.progress_template(ctx, node_index, result_template.application, result_template.template)?;
 
        let arg1_template_progress = self.progress_template(ctx, arg1_index, argument_template.application, argument_template.template)?;
 
        let (arg1_progress, arg2_progress) = self.apply_equal2_constraint(ctx, node_index, arg1_index, 0, arg2_index, 0)?;
 

	
 
        if self_template_progress { self.queue_node_parent(node_index); }
 
        if arg1_template_progress || arg1_progress { self.queue_node(arg1_index); }
 
        if arg2_progress { self.queue_node(arg2_index); }
 

	
 
        return Ok(());
 
    }
 

	
 
    fn progress_inference_rule_tri_equal_all(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let rule = node.inference_rule.as_tri_equal_all();
 

	
 
        let template = rule.template;
 
        let arg1_index = rule.argument1_index;
 
        let arg2_index = rule.argument2_index;
 

	
 
        let template_progress = self.progress_template(ctx, node_index, template.application, template.template)?;
 
        let (node_progress, arg1_progress, arg2_progress) =
 
            self.apply_equal3_constraint(ctx, node_index, arg1_index, arg2_index, 0)?;
 

	
 
        if template_progress || node_progress { self.queue_node_parent(node_index); }
 
        if arg1_progress { self.queue_node(arg1_index); }
 
        if arg2_progress { self.queue_node(arg2_index); }
 

	
 
        return Ok(());
 
    }
 

	
 
    fn progress_inference_rule_concatenate(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let rule = node.inference_rule.as_concatenate();
 
        let arg1_index = rule.argument1_index;
 
        let arg2_index = rule.argument2_index;
 

	
 
        // Two cases: one of the arguments is a string (then all must be), or
 
        // one of the arguments is an array (and all must be arrays).
 
        let (expr_is_str, expr_is_not_str) = self.type_is_certainly_or_certainly_not_string(node_index);
 
        let (arg1_is_str, arg1_is_not_str) = self.type_is_certainly_or_certainly_not_string(arg1_index);
 
        let (arg2_is_str, arg2_is_not_str) = self.type_is_certainly_or_certainly_not_string(arg2_index);
 

	
 
        let someone_is_str = expr_is_str || arg1_is_str || arg2_is_str;
 
        let someone_is_not_str = expr_is_not_str || arg1_is_not_str || arg2_is_not_str;
 
        // Note: this statement is an expression returning the progression bools
 
        let (node_progress, arg1_progress, arg2_progress) = if someone_is_str {
 
            // One of the arguments is a string, then all must be strings
 
            self.apply_equal3_constraint(ctx, node_index, arg1_index, arg2_index, 0)?
 
        } else {
 
            let progress_expr = if someone_is_not_str {
 
                // Output must be a normal array
 
                self.apply_template_constraint(ctx, node_index, &ARRAY_TEMPLATE)?
 
            } else {
 
                // Output may still be anything
 
                self.apply_template_constraint(ctx, node_index, &ARRAYLIKE_TEMPLATE)?
 
            };
 

	
 
            let progress_arg1 = self.apply_template_constraint(ctx, arg1_index, &ARRAYLIKE_TEMPLATE)?;
 
            let progress_arg2 = self.apply_template_constraint(ctx, arg2_index, &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, node_index, arg1_index, arg2_index, 1)?;
 

	
 
            (progress_expr || subtype_expr, progress_arg1 || subtype_arg1, progress_arg2 || subtype_arg2)
 
        };
 

	
 
        if node_progress { self.queue_node_parent(node_index); }
 
        if arg1_progress { self.queue_node(arg1_index); }
 
        if arg2_progress { self.queue_node(arg2_index); }
 

	
 
        return Ok(())
 
    }
 

	
 
    fn progress_inference_rule_indexing_expr(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let rule = node.inference_rule.as_indexing_expr();
 
        let subject_index = rule.subject_index;
 
        let index_index = rule.index_index; // which one?
 

	
 
        // Subject is arraylike, index in integerlike
 
        let subject_template_progress = self.apply_template_constraint(ctx, subject_index, &ARRAYLIKE_TEMPLATE)?;
 
        let index_template_progress = self.apply_template_constraint(ctx, index_index, &INTEGERLIKE_TEMPLATE)?;
 

	
 
        // If subject is type `Array<T>`, then expr type is `T`
 
        let (node_progress, subject_progress) =
 
            self.apply_equal2_constraint(ctx, node_index, node_index, 0, subject_index, 1)?;
 

	
 
        if node_progress { self.queue_node_parent(node_index); }
 
        if subject_template_progress || subject_progress { self.queue_node(subject_index); }
 
        if index_template_progress { self.queue_node(index_index); }
 

	
 
        return Ok(());
 
    }
 

	
 
    fn progress_inference_rule_slicing_expr(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let rule = node.inference_rule.as_slicing_expr();
 
        let subject_index = rule.subject_index;
 
        let from_index_index = rule.from_index;
 
        let to_index_index = rule.to_index;
 

	
 
        debug_log!("Rule slicing [node: {}, expr: {}]", node_index, node.expr_id.index);
 

	
 
        // Subject is arraylike, indices are integerlike
 
        let subject_template_progress = self.apply_template_constraint(ctx, subject_index, &ARRAYLIKE_TEMPLATE)?;
 
        let from_template_progress = self.apply_template_constraint(ctx, from_index_index, &INTEGERLIKE_TEMPLATE)?;
 
        let to_template_progress = self.apply_template_constraint(ctx, to_index_index, &INTEGERLIKE_TEMPLATE)?;
 
        let (from_index_progress, to_index_progress) =
 
            self.apply_equal2_constraint(ctx, node_index, from_index_index, 0, to_index_index, 0)?;
 

	
 
        // Same as array indexing: result depends on whether subject is string
 
        // or array
 
        let (is_string, is_not_string) = self.type_is_certainly_or_certainly_not_string(node_index);
 
        let (node_progress, subject_progress) = if is_string {
 
            // Certainly a string
 
            (
 
                self.apply_forced_constraint(ctx, node_index, &STRING_TEMPLATE)?,
 
                false
 
            )
 
        } else if is_not_string {
 
            // Certainly not a string, apply template constraint. Then make sure
 
            // that if we have an `Array<T>`, that the slice produces `Slice<T>`
 
            let node_template_progress = self.apply_template_constraint(ctx, node_index, &SLICE_TEMPLATE)?;
 
            let (node_progress, subject_progress) =
 
                self.apply_equal2_constraint(ctx, node_index, node_index, 1, subject_index, 1)?;
 

	
 
            (
 
                node_template_progress || node_progress,
 
                subject_progress
 
            )
 
        } else {
 
            // Not sure yet
 
            let node_template_progress = self.apply_template_constraint(ctx, node_index, &ARRAYLIKE_TEMPLATE)?;
 
            let (node_progress, subject_progress) =
 
                self.apply_equal2_constraint(ctx, node_index, node_index, 1, subject_index, 1)?;
 

	
 
            (
 
                node_template_progress || node_progress,
 
                subject_progress
 
            )
 
        };
 

	
 
        if node_progress { self.queue_node_parent(node_index); }
 
        if subject_template_progress || subject_progress { self.queue_node(subject_index); }
 
        if from_template_progress || from_index_progress { self.queue_node(from_index_index); }
 
        if to_template_progress || to_index_progress { self.queue_node(to_index_index); }
 

	
 
        return Ok(());
 
    }
 

	
 
    fn progress_inference_rule_select_struct_field(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let rule = node.inference_rule.as_select_struct_field();
 

	
 
        let subject_index = rule.subject_index;
 
@@ -2485,559 +2497,571 @@ impl PassTyping {
 
        if progress_field_1 || progress_field_2 { self.queue_node_parent(node_index); }
 

	
 
        poly_progress_section.forget();
 
        self.finish_polydata_constraint(node_index);
 
        return Ok(())
 
    }
 

	
 
    fn progress_inference_rule_select_tuple_member(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let rule = node.inference_rule.as_select_tuple_member();
 
        let subject_index = rule.subject_index;
 
        let tuple_member_index = rule.selected_index;
 

	
 
        if node.field_index < 0 {
 
            let subject_type = &self.infer_nodes[subject_index].expr_type;
 
            let tuple_size = get_tuple_size_from_inference_type(subject_type);
 
            let tuple_size = match tuple_size {
 
                Ok(Some(tuple_size)) => {
 
                    tuple_size
 
                },
 
                Ok(None) => {
 
                    // We can't infer anything yet
 
                    return Ok(())
 
                },
 
                Err(()) => {
 
                    let select_expr_span = ctx.heap[node.expr_id].full_span();
 
                    return Err(ParseError::new_error_at_span(
 
                        &ctx.module().source, select_expr_span, format!(
 
                            "tuple element select cannot be applied to a subject of type '{}'",
 
                            subject_type.display_name(&ctx.heap)
 
                        )
 
                    ));
 
                }
 
            };
 

	
 
            // If here then we at least have the tuple size. Now check if the
 
            // index doesn't exceed that size.
 
            if tuple_member_index >= tuple_size as u64 {
 
                let select_expr_span = ctx.heap[node.expr_id].full_span();
 
                return Err(ParseError::new_error_at_span(
 
                    &ctx.module().source, select_expr_span, format!(
 
                        "element index {} is out of bounds, tuple has {} elements",
 
                        tuple_member_index, tuple_size
 
                    )
 
                ));
 
            }
 

	
 
            // Within bounds, set index on the type inference node
 
            let node = &mut self.infer_nodes[node_index];
 
            node.field_index = tuple_member_index as i32;
 
        }
 

	
 
        // If here then we know we can use `tuple_member_index`. We need to keep
 
        // computing the offset to the subtype, as its value changes during
 
        // inference
 
        let subject_type = &self.infer_nodes[subject_index].expr_type;
 
        let mut selected_member_start_index = 1; // start just after the InferenceTypeElement::Tuple
 
        for _ in 0..tuple_member_index {
 
            selected_member_start_index = InferenceType::find_subtree_end_idx(&subject_type.parts, selected_member_start_index);
 
        }
 

	
 
        let (progress_member, progress_subject) = self.apply_equal2_constraint(
 
            ctx, node_index, node_index, 0, subject_index, selected_member_start_index
 
        )?;
 

	
 
        if progress_member { self.queue_node_parent(node_index); }
 
        if progress_subject { self.queue_node(subject_index); }
 

	
 
        return Ok(());
 
    }
 

	
 
    fn progress_inference_rule_literal_struct(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let node_expr_id = node.expr_id;
 
        let rule = node.inference_rule.as_literal_struct();
 

	
 
        // For each of the fields in the literal struct, apply the type equality
 
        // constraint. If the literal is polymorphic, then we try to progress
 
        // their types during this process
 
        let element_indices_section = self.index_buffer.start_section_initialized(&rule.element_indices);
 
        let mut poly_progress_section = self.poly_progress_buffer.start_section();
 
        for (field_index, field_node_index) in element_indices_section.iter_copied().enumerate() {
 
            let field_expr_id = self.infer_nodes[field_node_index].expr_id;
 
            let (_, progress_field) = self.apply_polydata_equal2_constraint(
 
                ctx, node_index, field_expr_id, "struct field's",
 
                PolyDataTypeIndex::Associated(field_index), 0,
 
                field_node_index, 0, &mut poly_progress_section
 
            )?;
 

	
 
            if progress_field { self.queue_node(field_node_index); }
 
        }
 

	
 
        // Now we do the same thing for the struct literal expression (the type
 
        // of the struct itself).
 
        let (_, progress_literal_1) = self.apply_polydata_equal2_constraint(
 
            ctx, node_index, node_expr_id, "struct literal's",
 
            PolyDataTypeIndex::Returned, 0, node_index, 0, &mut poly_progress_section
 
        )?;
 

	
 
        // And the other way around: if any of our polymorphic variables are
 
        // more specific then they were before, then we forward that information
 
        // back to our struct/fields.
 
        for (field_index, field_node_index) in element_indices_section.iter_copied().enumerate() {
 
            let progress_field = self.apply_polydata_polyvar_constraint(
 
                ctx, node_index, PolyDataTypeIndex::Associated(field_index),
 
                field_node_index, &poly_progress_section
 
            );
 

	
 
            if progress_field { self.queue_node(field_node_index); }
 
        }
 

	
 
        let progress_literal_2 = self.apply_polydata_polyvar_constraint(
 
            ctx, node_index, PolyDataTypeIndex::Returned,
 
            node_index, &poly_progress_section
 
        );
 

	
 
        if progress_literal_1 || progress_literal_2 { self.queue_node_parent(node_index); }
 

	
 
        poly_progress_section.forget();
 
        element_indices_section.forget();
 

	
 
        self.finish_polydata_constraint(node_index);
 
        return Ok(())
 
    }
 

	
 
    fn progress_inference_rule_literal_enum(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let node_expr_id = node.expr_id;
 
        let mut poly_progress_section = self.poly_progress_buffer.start_section();
 

	
 
        // An enum literal type is simply, well, the enum's type. However, it
 
        // might still have polymorphic variables, hence the use of `PolyData`.
 
        let (_, progress_literal_1) = self.apply_polydata_equal2_constraint(
 
            ctx, node_index, node_expr_id, "enum literal's",
 
            PolyDataTypeIndex::Returned, 0, node_index, 0, &mut poly_progress_section
 
        )?;
 

	
 
        let progress_literal_2 = self.apply_polydata_polyvar_constraint(
 
            ctx, node_index, PolyDataTypeIndex::Returned, node_index, &poly_progress_section
 
        );
 

	
 
        if progress_literal_1 || progress_literal_2 { self.queue_node_parent(node_index); }
 

	
 
        poly_progress_section.forget();
 
        self.finish_polydata_constraint(node_index);
 
        return Ok(());
 
    }
 

	
 
    fn progress_inference_rule_literal_union(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let node_expr_id = node.expr_id;
 
        let rule = node.inference_rule.as_literal_union();
 

	
 
        // Infer type of any embedded values in the union variant. At the same
 
        // time progress the polymorphic variables associated with the union.
 
        let element_indices_section = self.index_buffer.start_section_initialized(&rule.element_indices);
 
        let mut poly_progress_section = self.poly_progress_buffer.start_section();
 

	
 
        for (embedded_index, embedded_node_index) in element_indices_section.iter_copied().enumerate() {
 
            let embedded_node_expr_id = self.infer_nodes[embedded_node_index].expr_id;
 
            let (_, progress_embedded) = self.apply_polydata_equal2_constraint(
 
                ctx, node_index, embedded_node_expr_id, "embedded value's",
 
                PolyDataTypeIndex::Associated(embedded_index), 0,
 
                embedded_node_index, 0, &mut poly_progress_section
 
            )?;
 

	
 
            if progress_embedded { self.queue_node(embedded_node_index); }
 
        }
 

	
 
        let (_, progress_literal_1) = self.apply_polydata_equal2_constraint(
 
            ctx, node_index, node_expr_id, "union's",
 
            PolyDataTypeIndex::Returned, 0, node_index, 0, &mut poly_progress_section
 
        )?;
 

	
 
        // Propagate progress in the polymorphic variables to the expressions
 
        // that constitute the union literal.
 
        for (embedded_index, embedded_node_index) in element_indices_section.iter_copied().enumerate() {
 
            let progress_embedded = self.apply_polydata_polyvar_constraint(
 
                ctx, node_index, PolyDataTypeIndex::Associated(embedded_index),
 
                embedded_node_index, &poly_progress_section
 
            );
 

	
 
            if progress_embedded { self.queue_node(embedded_node_index); }
 
        }
 

	
 
        let progress_literal_2 = self.apply_polydata_polyvar_constraint(
 
            ctx, node_index, PolyDataTypeIndex::Returned, node_index, &poly_progress_section
 
        );
 

	
 
        if progress_literal_1 || progress_literal_2 { self.queue_node_parent(node_index); }
 

	
 
        poly_progress_section.forget();
 
        element_indices_section.forget();
 

	
 
        self.finish_polydata_constraint(node_index);
 
        return Ok(());
 
    }
 

	
 
    fn progress_inference_rule_literal_array(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let rule = node.inference_rule.as_literal_array();
 

	
 
        // Apply equality rule to all of the elements that form the array
 
        let argument_node_indices = self.index_buffer.start_section_initialized(&rule.element_indices);
 
        let mut argument_progress_section = self.bool_buffer.start_section();
 
        self.apply_equal_n_constraint(ctx, node_index, &argument_node_indices, &mut argument_progress_section)?;
 

	
 
        debug_assert_eq!(argument_node_indices.len(), argument_progress_section.len());
 
        for argument_index in 0..argument_node_indices.len() {
 
            let argument_node_index = argument_node_indices[argument_index];
 
            let progress = argument_progress_section[argument_index];
 

	
 
            if progress { self.queue_node(argument_node_index); }
 
        }
 

	
 
        // If elements are of type `T`, then the array is of type `Array<T>`, so:
 
        let mut progress_literal = self.apply_template_constraint(ctx, node_index, &ARRAY_TEMPLATE)?;
 
        if argument_node_indices.len() != 0 {
 
            let argument_node_index = argument_node_indices[0];
 
            let (progress_literal_inner, progress_argument) = self.apply_equal2_constraint(
 
                ctx, node_index, node_index, 1, argument_node_index, 0
 
            )?;
 

	
 
            progress_literal = progress_literal || progress_literal_inner;
 

	
 
            // It is possible that the `Array<T>` has a more progress `T` then
 
            // the arguments. So in the case we progress our argument type we
 
            // simply queue this rule again
 
            if progress_argument { self.queue_node(node_index); }
 
        }
 

	
 
        argument_node_indices.forget();
 
        argument_progress_section.forget();
 

	
 
        if progress_literal { self.queue_node_parent(node_index); }
 
        return Ok(());
 
    }
 

	
 
    fn progress_inference_rule_literal_tuple(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let rule = node.inference_rule.as_literal_tuple();
 

	
 
        let element_indices = self.index_buffer.start_section_initialized(&rule.element_indices);
 

	
 
        // Check if we need to apply the initial tuple template type. Note that
 
        // this is a hacky check.
 
        let num_tuple_elements = rule.element_indices.len();
 
        let mut template_type = Vec::with_capacity(num_tuple_elements + 1); // TODO: @performance
 
        template_type.push(InferenceTypePart::Tuple(num_tuple_elements as u32));
 
        for _ in 0..num_tuple_elements {
 
            template_type.push(InferenceTypePart::Unknown);
 
        }
 

	
 
        let mut progress_literal = self.apply_template_constraint(ctx, node_index, &template_type)?;
 

	
 
        // Because of the (early returning error) check above, we're certain
 
        // that the tuple has the correct number of elements. Now match each
 
        // element expression type to the tuple subtype.
 
        let mut element_subtree_start_index = 1; // first element is InferenceTypePart::Tuple
 
        for element_node_index in element_indices.iter_copied() {
 
            let (progress_literal_element, progress_element) = self.apply_equal2_constraint(
 
                ctx, node_index, node_index, element_subtree_start_index, element_node_index, 0
 
            )?;
 

	
 
            progress_literal = progress_literal || progress_literal_element;
 
            if progress_element {
 
                self.queue_node(element_node_index);
 
            }
 

	
 
            // Prepare for next element
 
            let node = &self.infer_nodes[node_index];
 
            let subtree_end_index = InferenceType::find_subtree_end_idx(&node.expr_type.parts, element_subtree_start_index);
 
            element_subtree_start_index = subtree_end_index;
 
        }
 
        debug_assert_eq!(element_subtree_start_index, self.infer_nodes[node_index].expr_type.parts.len());
 

	
 
        if progress_literal { self.queue_node_parent(node_index); }
 

	
 
        element_indices.forget();
 
        return Ok(());
 
    }
 

	
 
    fn progress_inference_rule_cast_expr(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let rule = node.inference_rule.as_cast_expr();
 
        let subject_index = rule.subject_index;
 
        let subject = &self.infer_nodes[subject_index];
 

	
 
        // Make sure that both types are completely done. Note: a cast
 
        // expression cannot really infer anything between the subject and the
 
        // output type, we can only make sure that, at the end, the cast is
 
        // correct.
 
        if !node.expr_type.is_done || !subject.expr_type.is_done {
 
            return Ok(());
 
        }
 

	
 
        // Both types are known, currently the only valid casts are bool,
 
        // integer and character casts.
 
        fn is_bool_int_or_char(parts: &[InferenceTypePart]) -> bool {
 
            let mut index = 0;
 
            while index < parts.len() {
 
                let part = &parts[index];
 
                if !part.is_marker() { break; }
 
                index += 1;
 
            }
 

	
 
            debug_assert!(index != parts.len());
 
            let part = &parts[index];
 
            if *part == InferenceTypePart::Bool || *part == InferenceTypePart::Character || part.is_concrete_integer() {
 
                debug_assert!(index + 1 == parts.len()); // type is done, first part does not have children -> must be at end
 
                return true;
 
            } else {
 
                return false;
 
            }
 
        }
 

	
 
        let is_valid = if is_bool_int_or_char(&node.expr_type.parts) && is_bool_int_or_char(&subject.expr_type.parts) {
 
            true
 
        } else if InferenceType::check_subtrees(&node.expr_type.parts, 0, &subject.expr_type.parts, 0) {
 
            // again: check_subtrees is sufficient since both types are done
 
            true
 
        } else {
 
            false
 
        };
 

	
 
        if !is_valid {
 
            let cast_expr = &ctx.heap[node.expr_id];
 
            let subject_expr = &ctx.heap[subject.expr_id];
 
            return Err(ParseError::new_error_str_at_span(
 
                &ctx.module().source, cast_expr.full_span(), "invalid casting operation"
 
            ).with_info_at_span(
 
                &ctx.module().source, subject_expr.full_span(), format!(
 
                    "cannot cast the argument type '{}' to the type '{}'",
 
                    subject.expr_type.display_name(&ctx.heap),
 
                    node.expr_type.display_name(&ctx.heap)
 
                )
 
            ));
 
        }
 

	
 
        return Ok(())
 
    }
 

	
 
    fn progress_inference_rule_call_expr(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &self.infer_nodes[node_index];
 
        let node_expr_id = node.expr_id;
 
        let rule = node.inference_rule.as_call_expr();
 

	
 
        debug_log!("Progressing call expression inference rule (node index {})", node_index);
 

	
 
        let mut poly_progress_section = self.poly_progress_buffer.start_section();
 
        let argument_node_indices = self.index_buffer.start_section_initialized(&rule.argument_indices);
 

	
 
        // Perform inference on arguments to function, while trying to figure
 
        // out the polymorphic variables
 
        for (argument_index, argument_node_index) in argument_node_indices.iter_copied().enumerate() {
 
            let argument_expr_id = self.infer_nodes[argument_node_index].expr_id;
 
            debug_log!(" * Argument {}: Provided by node index {}", argument_index, argument_node_index);
 
            debug_log!(" * --- Pre:  {}", self.infer_nodes[argument_node_index].expr_type.display_name(&ctx.heap));
 
            let (_, progress_argument) = self.apply_polydata_equal2_constraint(
 
                ctx, node_index, argument_expr_id, "argument's",
 
                PolyDataTypeIndex::Associated(argument_index), 0,
 
                argument_node_index, 0, &mut poly_progress_section
 
            )?;
 
            debug_log!(" * --- Post: {}", self.infer_nodes[argument_node_index].expr_type.display_name(&ctx.heap));
 
            debug_log!(" * --- Progression: {}", progress_argument);
 

	
 
            if progress_argument { self.queue_node(argument_node_index); }
 
        }
 

	
 
        // Same for the return type.
 
        debug_log!(" * Return type: Provided by node index {}", node_index);
 
        debug_log!(" * --- Pre:  {}", self.infer_nodes[node_index].expr_type.display_name(&ctx.heap));
 
        let (_, progress_call_1) = self.apply_polydata_equal2_constraint(
 
            ctx, node_index, node_expr_id, "return",
 
            PolyDataTypeIndex::Returned, 0,
 
            node_index, 0, &mut poly_progress_section
 
        )?;
 
        debug_log!(" * --- Post: {}", self.infer_nodes[node_index].expr_type.display_name(&ctx.heap));
 
        debug_log!(" * --- Progression: {}", progress_call_1);
 

	
 
        // We will now apply any progression in the polymorphic variable type
 
        // back to the arguments.
 
        for (argument_index, argument_node_index) in argument_node_indices.iter_copied().enumerate() {
 
            let progress_argument = self.apply_polydata_polyvar_constraint(
 
                ctx, node_index, PolyDataTypeIndex::Associated(argument_index),
 
                argument_node_index, &poly_progress_section
 
            );
 

	
 
            if progress_argument { self.queue_node(argument_node_index); }
 
        }
 

	
 
        // And back to the return type.
 
        let progress_call_2 = self.apply_polydata_polyvar_constraint(
 
            ctx, node_index, PolyDataTypeIndex::Returned,
 
            node_index, &poly_progress_section
 
        );
 

	
 
        if progress_call_1 || progress_call_2 { self.queue_node_parent(node_index); }
 

	
 
        poly_progress_section.forget();
 
        argument_node_indices.forget();
 

	
 
        self.finish_polydata_constraint(node_index);
 
        return Ok(())
 
    }
 

	
 
    fn progress_inference_rule_variable_expr(&mut self, ctx: &Ctx, node_index: InferNodeIndex) -> Result<(), ParseError> {
 
        let node = &mut self.infer_nodes[node_index];
 
        let rule = node.inference_rule.as_variable_expr();
 
        let var_data_index = rule.var_data_index;
 

	
 
        let var_data = &mut self.var_data[var_data_index];
 
        // Apply inference to the shared variable type and the expression type
 
        let shared_type: *mut _ = &mut var_data.var_type;
 
        let expr_type: *mut _ = &mut node.expr_type;
 

	
 
        let inference_result = unsafe {
 
            // safety: vectors exist in different storage vectors, so cannot alias
 
            InferenceType::infer_subtrees_for_both_types(shared_type, 0, expr_type, 0)
 
        };
 

	
 
        if inference_result == DualInferenceResult::Incompatible {
 
            return Err(self.construct_variable_type_error(ctx, node_index));
 
        }
 

	
 
        let progress_var_data = inference_result.modified_lhs();
 
        let progress_expr = inference_result.modified_rhs();
 

	
 
        if progress_var_data {
 
            // We progressed the type of the shared variable, so propagate this
 
            // to all associated variable expressions (and relatived variables).
 
            for other_node_index in var_data.used_at.iter().copied() {
 
                if other_node_index != node_index {
 
                    self.node_queued.push_back(other_node_index);
 
                }
 
            }
 

	
 
            if let Some(linked_var_data_index) = var_data.linked_var {
 
                // Only perform one-way inference, progressing the linked
 
                // variable.
 
                // note: because this "linking" is used only for channels, we
 
                // will start inference one level below the top-level in the
 
                // type tree (i.e. ensure `T` in `in<T>` and `out<T>` is equal).
 
                debug_assert!(
 
                    var_data.var_type.parts[0] == InferenceTypePart::Input ||
 
                    var_data.var_type.parts[0] == InferenceTypePart::Output
 
                );
 
                let this_var_type: *const _ = &var_data.var_type;
 
                let linked_var_data = &mut self.var_data[linked_var_data_index];
 
                debug_assert!(
 
                    linked_var_data.var_type.parts[0] == InferenceTypePart::Input ||
 
                    linked_var_data.var_type.parts[0] == InferenceTypePart::Output
 
                );
 

	
 
                // safety: by construction var_data_index and linked_var_data_index cannot be the
 
                // same, hence we're not aliasing here.
 
                let inference_result = InferenceType::infer_subtree_for_single_type(
 
                    &mut linked_var_data.var_type, 1,
 
                    unsafe{ &(*this_var_type).parts }, 1, false
 
                );
 
                match inference_result {
 
                    SingleInferenceResult::Modified => {
 
                        for used_at in linked_var_data.used_at.iter().copied() {
 
                            self.node_queued.push_back(used_at);
 
                        }
 
                    },
 
                    SingleInferenceResult::Unmodified => {},
 
                    SingleInferenceResult::Incompatible => {
 
                        let var_data_this = &self.var_data[var_data_index];
 
                        let var_decl_this = &ctx.heap[var_data_this.var_id];
 
                        let var_data_linked = &self.var_data[linked_var_data_index];
 
                        let var_decl_linked = &ctx.heap[var_data_linked.var_id];
 

	
 
                        return Err(ParseError::new_error_at_span(
 
                            &ctx.module().source, var_decl_this.identifier.span, format!(
 
                                "conflicting types for this channel, this port has type '{}'",
 
                                var_data_this.var_type.display_name(&ctx.heap)
 
                            )
 
                        ).with_info_at_span(
 
                            &ctx.module().source, var_decl_linked.identifier.span, format!(
 
                                "while this port has type '{}'",
 
                                var_data_linked.var_type.display_name(&ctx.heap)
 
                            )
 
                        ));
 
                    }
 
                }
 
            }
 
        }
 

	
 
        if progress_expr { self.queue_node_parent(node_index); }
 

	
 
        return Ok(());
 
    }
 

	
 
    fn progress_template(&mut self, ctx: &Ctx, node_index: InferNodeIndex, application: InferenceRuleTemplateApplication, template: &[InferenceTypePart]) -> Result<bool, ParseError> {
 
        use InferenceRuleTemplateApplication as TA;
 

	
 
        match application {
 
            TA::None => Ok(false),
 
            TA::Template => self.apply_template_constraint(ctx, node_index, template),
 
            TA::Forced => self.apply_forced_constraint(ctx, node_index, template),
 
        }
 
    }
 

	
 
    fn queue_node_parent(&mut self, node_index: InferNodeIndex) {
 
        let node = &self.infer_nodes[node_index];
 
        if let Some(parent_node_index) = node.parent_index {
 
            self.node_queued.push_back(parent_node_index);
 
        }
 
    }
 

	
 
    #[inline]
 
    fn queue_node(&mut self, node_index: InferNodeIndex) {
 
        self.node_queued.push_back(node_index);
 
    }
 

	
 
    /// Returns whether the type is certainly a string (true, false), certainly
 
    /// not a string (false, true), or still unknown (false, false).
 
    fn type_is_certainly_or_certainly_not_string(&self, node_index: InferNodeIndex) -> (bool, bool) {
 
        let expr_type = &self.infer_nodes[node_index].expr_type;
 
        let mut part_index = 0;
 
        while part_index < expr_type.parts.len() {
 
            let part = &expr_type.parts[part_index];
 

	
 
            if part.is_marker() {
 
                part_index += 1;
 
                continue;
 
            }
 
            if !part.is_concrete() { break; }
 

	
 
            if *part == InferenceTypePart::String {
 
                // First part is a string
 
                return (true, false);
 
            } else {
 
                return (false, true);
 
            }
 
        }
 

	
 
        // If here then first non-marker type is not concrete
 
        if part_index == expr_type.parts.len() {
 
            // nothing known at all
 
            return (false, false);
 
        }
 

	
 
        // Special case: array-like where its argument is not a character
 
        if part_index + 1 < expr_type.parts.len() {
 
            if expr_type.parts[part_index] == InferenceTypePart::ArrayLike && expr_type.parts[part_index + 1] != InferenceTypePart::Character {
 
                return (false, true);
 
            }
 
        }
 

	
 

	
 
        (false, false)
 
    }
 

	
 
    /// Applies a template type constraint: the type associated with the
 
    /// supplied expression will be molded into the provided `template`. But
 
    /// will be considered valid if the template could've been molded into the
 
    /// expression type as well. Hence the template may be fully specified (e.g.
 
    /// a bool) or contain "inference" variables (e.g. an array of T)
 
    fn apply_template_constraint(
 
        &mut self, ctx: &Ctx, node_index: InferNodeIndex, template: &[InferenceTypePart]
 
    ) -> Result<bool, ParseError> {
 
        let expr_type = &mut self.infer_nodes[node_index].expr_type;
 
        match InferenceType::infer_subtree_for_single_type(expr_type, 0, template, 0, false) {
 
            SingleInferenceResult::Modified => Ok(true),
 
            SingleInferenceResult::Unmodified => Ok(false),
 
            SingleInferenceResult::Incompatible => Err(
 
                self.construct_template_type_error(ctx, node_index, template)
 
            )
 
        }
src/protocol/parser/pass_validation_linking.rs
Show inline comments
 
@@ -713,385 +713,386 @@ impl Visitor for PassValidationLinking {
 

	
 
        // Perform preliminary check on children: binding expressions only make
 
        // sense if the left hand side is just a variable expression, or if it
 
        // is a literal of some sort. The typechecker will take care of the rest
 
        let bound_to_id = binding_expr.bound_to;
 
        let bound_from_id = binding_expr.bound_from;
 

	
 
        match &ctx.heap[bound_to_id] {
 
            // Variables may not be binding variables, and literals may
 
            // actually not contain binding variables. But in that case we just
 
            // perform an equality check.
 
            Expression::Variable(_) => {}
 
            Expression::Literal(_) => {},
 
            _ => {
 
                let binding_expr = &ctx.heap[id];
 
                return Err(ParseError::new_error_str_at_span(
 
                    &ctx.module().source, binding_expr.operator_span,
 
                    "the left hand side of a binding expression may only be a variable or a literal expression"
 
                ));
 
            },
 
        }
 

	
 
        // Visit the children themselves
 
        self.in_binding_expr_lhs = true;
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
 
        self.visit_expr(ctx, bound_to_id)?;
 
        self.in_binding_expr_lhs = false;
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
 
        self.visit_expr(ctx, bound_from_id)?;
 

	
 
        self.expr_parent = old_expr_parent;
 
        self.in_binding_expr = BindingExpressionId::new_invalid();
 

	
 
        Ok(())
 
    }
 

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

	
 
        if let Some(span) = self.must_be_assignable {
 
            return Err(ParseError::new_error_str_at_span(
 
                &ctx.module().source, span, "cannot assign to the result from a conditional expression"
 
            ))
 
        }
 

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

	
 
        if let Some(span) = self.must_be_assignable {
 
            return Err(ParseError::new_error_str_at_span(
 
                &ctx.module().source, span, "cannot assign to the result from a binary expression"
 
            ))
 
        }
 

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

	
 
        if let Some(span) = self.must_be_assignable {
 
            return Err(ParseError::new_error_str_at_span(
 
                &ctx.module().source, span, "cannot assign to the result from a unary 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 {
 
        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)?;
 

	
 
        let old_assignable = self.must_be_assignable.take();
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
 
        self.visit_expr(ctx, index_expr_id)?;
 

	
 
        self.must_be_assignable = old_assignable;
 
        self.expr_parent = old_expr_parent;
 

	
 
        Ok(())
 
    }
 

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

	
 
        if let Some(span) = self.must_be_assignable {
 
            // TODO: @Slicing
 
            return Err(ParseError::new_error_str_at_span(
 
                &ctx.module().source, span, "assignment to slices should be valid in the final language, but is currently not implemented"
 
            ));
 
        }
 

	
 
        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)?;
 

	
 
        let old_assignable = self.must_be_assignable.take();
 
        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.must_be_assignable = old_assignable;
 
        self.expr_parent = old_expr_parent;
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_select_expr(&mut self, ctx: &mut Ctx, id: SelectExpressionId) -> VisitorResult {
 
        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_literal_expr(&mut self, ctx: &mut Ctx, id: LiteralExpressionId) -> VisitorResult {
 
        let literal_expr = &mut ctx.heap[id];
 
        let old_expr_parent = self.expr_parent;
 
        literal_expr.parent = old_expr_parent;
 

	
 
        if let Some(span) = self.must_be_assignable {
 
            return Err(ParseError::new_error_str_at_span(
 
                &ctx.module().source, span, "cannot assign to a literal expression"
 
            ))
 
        }
 

	
 
        match &mut literal_expr.value {
 
            Literal::Null | Literal::True | Literal::False |
 
            Literal::Character(_) | Literal::String(_) | Literal::Integer(_) => {
 
            Literal::Character(_) | Literal::Bytestring(_) | Literal::String(_) |
 
            Literal::Integer(_) => {
 
                // Just the parent has to be set, done above
 
            },
 
            Literal::Struct(literal) => {
 
                let upcast_id = id.upcast();
 
                // Retrieve type definition
 
                let type_definition = ctx.types.get_base_definition(&literal.definition).unwrap();
 
                let struct_definition = type_definition.definition.as_struct();
 

	
 
                // Make sure all fields are specified, none are specified twice
 
                // and all fields exist on the struct definition
 
                let mut specified = Vec::new(); // TODO: @performance
 
                specified.resize(struct_definition.fields.len(), false);
 

	
 
                for field in &mut literal.fields {
 
                    // Find field in the struct definition
 
                    let field_idx = struct_definition.fields.iter().position(|v| v.identifier == field.identifier);
 
                    if field_idx.is_none() {
 
                        let field_span = field.identifier.span;
 
                        let literal = ctx.heap[id].value.as_struct();
 
                        let ast_definition = &ctx.heap[literal.definition];
 
                        return Err(ParseError::new_error_at_span(
 
                            &ctx.module().source, field_span, format!(
 
                                "This field does not exist on the struct '{}'",
 
                                ast_definition.identifier().value.as_str()
 
                            )
 
                        ));
 
                    }
 
                    field.field_idx = field_idx.unwrap();
 

	
 
                    // Check if specified more than once
 
                    if specified[field.field_idx] {
 
                        let field_span = field.identifier.span;
 
                        return Err(ParseError::new_error_str_at_span(
 
                            &ctx.module().source, field_span,
 
                            "This field is specified more than once"
 
                        ));
 
                    }
 

	
 
                    specified[field.field_idx] = true;
 
                }
 

	
 
                if !specified.iter().all(|v| *v) {
 
                    // Some fields were not specified
 
                    let mut not_specified = String::new();
 
                    let mut num_not_specified = 0;
 
                    for (def_field_idx, is_specified) in specified.iter().enumerate() {
 
                        if !is_specified {
 
                            if !not_specified.is_empty() { not_specified.push_str(", ") }
 
                            let field_ident = &struct_definition.fields[def_field_idx].identifier;
 
                            not_specified.push_str(field_ident.value.as_str());
 
                            num_not_specified += 1;
 
                        }
 
                    }
 

	
 
                    debug_assert!(num_not_specified > 0);
 
                    let msg = if num_not_specified == 1 {
 
                        format!("not all fields are specified, '{}' is missing", not_specified)
 
                    } else {
 
                        format!("not all fields are specified, [{}] are missing", not_specified)
 
                    };
 

	
 
                    let literal_span = literal.parser_type.full_span;
 
                    return Err(ParseError::new_error_at_span(
 
                        &ctx.module().source, literal_span, msg
 
                    ));
 
                }
 

	
 
                // Need to traverse fields expressions in struct and evaluate
 
                // the poly args
 
                let mut expr_section = self.expression_buffer.start_section();
 
                for field in &literal.fields {
 
                    expr_section.push(field.value);
 
                }
 

	
 
                for expr_idx in 0..expr_section.len() {
 
                    let expr_id = expr_section[expr_idx];
 
                    self.expr_parent = ExpressionParent::Expression(upcast_id, expr_idx as u32);
 
                    self.visit_expr(ctx, expr_id)?;
 
                }
 

	
 
                expr_section.forget();
 
            },
 
            Literal::Enum(literal) => {
 
                // Make sure the variant exists
 
                let type_definition = ctx.types.get_base_definition(&literal.definition).unwrap();
 
                let enum_definition = type_definition.definition.as_enum();
 

	
 
                let variant_idx = enum_definition.variants.iter().position(|v| {
 
                    v.identifier == literal.variant
 
                });
 

	
 
                if variant_idx.is_none() {
 
                    let literal = ctx.heap[id].value.as_enum();
 
                    let ast_definition = ctx.heap[literal.definition].as_enum();
 
                    return Err(ParseError::new_error_at_span(
 
                        &ctx.module().source, literal.parser_type.full_span, format!(
 
                            "the variant '{}' does not exist on the enum '{}'",
 
                            literal.variant.value.as_str(), ast_definition.identifier.value.as_str()
 
                        )
 
                    ));
 
                }
 

	
 
                literal.variant_idx = variant_idx.unwrap();
 
            },
 
            Literal::Union(literal) => {
 
                // Make sure the variant exists
 
                let type_definition = ctx.types.get_base_definition(&literal.definition).unwrap();
 
                let union_definition = type_definition.definition.as_union();
 

	
 
                let variant_idx = union_definition.variants.iter().position(|v| {
 
                    v.identifier == literal.variant
 
                });
 
                if variant_idx.is_none() {
 
                    let literal = ctx.heap[id].value.as_union();
 
                    let ast_definition = ctx.heap[literal.definition].as_union();
 
                    return Err(ParseError::new_error_at_span(
 
                        &ctx.module().source, literal.parser_type.full_span, format!(
 
                            "the variant '{}' does not exist on the union '{}'",
 
                            literal.variant.value.as_str(), ast_definition.identifier.value.as_str()
 
                        )
 
                    ));
 
                }
 

	
 
                literal.variant_idx = variant_idx.unwrap();
 

	
 
                // Make sure the number of specified values matches the expected
 
                // number of embedded values in the union variant.
 
                let union_variant = &union_definition.variants[literal.variant_idx];
 
                if union_variant.embedded.len() != literal.values.len() {
 
                    let literal = ctx.heap[id].value.as_union();
 
                    let ast_definition = ctx.heap[literal.definition].as_union();
 
                    return Err(ParseError::new_error_at_span(
 
                        &ctx.module().source, literal.parser_type.full_span, format!(
 
                            "The variant '{}' of union '{}' expects {} embedded values, but {} were specified",
 
                            literal.variant.value.as_str(), ast_definition.identifier.value.as_str(),
 
                            union_variant.embedded.len(), literal.values.len()
 
                        ),
 
                    ))
 
                }
 

	
 
                // Traverse embedded values of union (if any) and evaluate the
 
                // polymorphic arguments
 
                let upcast_id = id.upcast();
 
                let mut expr_section = self.expression_buffer.start_section();
 
                for value in &literal.values {
 
                    expr_section.push(*value);
 
                }
 

	
 
                for expr_idx in 0..expr_section.len() {
 
                    let expr_id = expr_section[expr_idx];
 
                    self.expr_parent = ExpressionParent::Expression(upcast_id, expr_idx as u32);
 
                    self.visit_expr(ctx, expr_id)?;
 
                }
 

	
 
                expr_section.forget();
 
            },
 
            Literal::Array(literal) | Literal::Tuple(literal) => {
 
                // Visit all expressions in the array
 
                let upcast_id = id.upcast();
 
                let expr_section = self.expression_buffer.start_section_initialized(literal);
 
                for expr_idx in 0..expr_section.len() {
 
                    let expr_id = expr_section[expr_idx];
 
                    self.expr_parent = ExpressionParent::Expression(upcast_id, expr_idx as u32);
 
                    self.visit_expr(ctx, expr_id)?;
 
                }
 

	
 
                expr_section.forget();
 
            }
 
        }
 

	
 
        self.expr_parent = old_expr_parent;
 

	
 
        Ok(())
 
    }
 

	
 
    fn visit_cast_expr(&mut self, ctx: &mut Ctx, id: CastExpressionId) -> VisitorResult {
 
        let cast_expr = &mut ctx.heap[id];
 

	
 
        if let Some(span) = self.must_be_assignable {
 
            return Err(ParseError::new_error_str_at_span(
 
                &ctx.module().source, span, "cannot assign to the result from a cast expression"
 
            ))
 
        }
 

	
 
        let upcast_id = id.upcast();
 
        let old_expr_parent = self.expr_parent;
 
        cast_expr.parent = old_expr_parent;
 

	
 
        // Recurse into the thing that we're casting
 
        self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
 
        let subject_id = cast_expr.subject;
 
        self.visit_expr(ctx, subject_id)?;

Changeset was too big and was cut off... Show full diff anyway

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