CSY/reowolf Changeset - 1811fe09856a · Centrum Wiskunde & Informatica (CWI)

Changeset - 1811fe09856a

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MH - 4 years ago 2021-03-19 19:31:26
contact@maxhenger.nl

more progress on function call inference

4 files changed:

src/protocol/ast.rs

src/protocol/lexer.rs

src/protocol/parser/type_resolver.rs

434

186

src/protocol/parser/utils.rs

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src/protocol/ast.rs

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@@ @@ -738,1578 +738,1579 @@ pub enum ParserTypeVariant { @@
 impl ParserTypeVariant {
     pub(crate) fn supports_polymorphic_args(&self) -> bool {
         use ParserTypeVariant::*;
         match self {
             Message | Bool | Byte | Short | Int | Long | String | IntegerLiteral | Inferred => false,
             _ => true
+        }
+    }
+}
 /// ParserType is a specification of a type during the parsing phase and initial
 /// linker/validator phase of the compilation process. These types may be
 /// (partially) inferred or represent literals (e.g. a integer whose bytesize is
 /// not yet determined).
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct ParserType {
     pub this: ParserTypeId,
     pub pos: InputPosition,
     pub variant: ParserTypeVariant,
+}
 /// SymbolicParserType is the specification of a symbolic type. During the
 /// parsing phase we will only store the identifier of the type. During the
 /// validation phase we will determine whether it refers to a user-defined type,
 /// or a polymorphic argument. After the validation phase it may still be the
 /// case that the resulting `variant` will not pass the typechecker.
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct SymbolicParserType {
     // Phase 1: parser
     pub identifier: NamespacedIdentifier,
     /// The user-specified polymorphic arguments. Zero-length implies that the
     /// user did not specify any of them, and they're either not needed or all
     /// need to be inferred. Otherwise the number of polymorphic arguments must
     /// match those of the corresponding definition
     pub poly_args: Vec<ParserTypeId>,
     // Phase 2: validation/linking (for types in function/component bodies) and
     //  type table construction (for embedded types of structs/unions)
     pub variant: Option<SymbolicParserTypeVariant>
+}
 /// Specifies whether the symbolic type points to an actual user-defined type,
 /// or whether it points to a polymorphic argument within the definition (e.g.
 /// a defined variable `T var` within a function `int func<T>()`
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub enum SymbolicParserTypeVariant {
     Definition(DefinitionId),
     // TODO: figure out if I need the DefinitionId here
     PolyArg(DefinitionId, usize), // index of polyarg in the definition
+}
 #[derive(Debug, Clone, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
 pub enum PrimitiveType {
     Input,
     Output,
     Message,
     Boolean,
     Byte,
     Short,
     Int,
     Long,
     Symbolic(PrimitiveSymbolic)
+}
 // TODO: @cleanup, remove PartialEq implementations
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct PrimitiveSymbolic {
     // Phase 1: parser
     pub(crate) identifier: NamespacedIdentifier,
     // Phase 2: typing
     pub(crate) definition: Option<DefinitionId>
+}
 impl PartialEq for PrimitiveSymbolic {
     fn eq(&self, other: &Self) -> bool {
         self.identifier == other.identifier
+    }
+}
 impl Eq for PrimitiveSymbolic{}
 #[derive(Debug, Clone, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
 pub struct Type {
     pub primitive: PrimitiveType,
     pub array: bool,
+}
 #[allow(dead_code)]
 impl Type {
     pub const INPUT: Type = Type { primitive: PrimitiveType::Input, array: false };
     pub const OUTPUT: Type = Type { primitive: PrimitiveType::Output, array: false };
     pub const MESSAGE: Type = Type { primitive: PrimitiveType::Message, array: false };
     pub const BOOLEAN: Type = Type { primitive: PrimitiveType::Boolean, array: false };
     pub const BYTE: Type = Type { primitive: PrimitiveType::Byte, array: false };
     pub const SHORT: Type = Type { primitive: PrimitiveType::Short, array: false };
     pub const INT: Type = Type { primitive: PrimitiveType::Int, array: false };
     pub const LONG: Type = Type { primitive: PrimitiveType::Long, array: false };
     pub const INPUT_ARRAY: Type = Type { primitive: PrimitiveType::Input, array: true };
     pub const OUTPUT_ARRAY: Type = Type { primitive: PrimitiveType::Output, array: true };
     pub const MESSAGE_ARRAY: Type = Type { primitive: PrimitiveType::Message, array: true };
     pub const BOOLEAN_ARRAY: Type = Type { primitive: PrimitiveType::Boolean, array: true };
     pub const BYTE_ARRAY: Type = Type { primitive: PrimitiveType::Byte, array: true };
     pub const SHORT_ARRAY: Type = Type { primitive: PrimitiveType::Short, array: true };
     pub const INT_ARRAY: Type = Type { primitive: PrimitiveType::Int, array: true };
     pub const LONG_ARRAY: Type = Type { primitive: PrimitiveType::Long, array: true };
+}
 impl Display for Type {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         match &self.primitive {
             PrimitiveType::Input => {
                 write!(f, "in")?;
+            }
             PrimitiveType::Output => {
                 write!(f, "out")?;
+            }
             PrimitiveType::Message => {
                 write!(f, "msg")?;
+            }
             PrimitiveType::Boolean => {
                 write!(f, "boolean")?;
+            }
             PrimitiveType::Byte => {
                 write!(f, "byte")?;
+            }
             PrimitiveType::Short => {
                 write!(f, "short")?;
+            }
             PrimitiveType::Int => {
                 write!(f, "int")?;
+            }
             PrimitiveType::Long => {
                 write!(f, "long")?;
+            }
             PrimitiveType::Symbolic(data) => {
                 // Type data is in ASCII range.
                 if let Some(id) = &data.definition {
                     write!(
                         f, "Symbolic({}, id: {})",
                         String::from_utf8_lossy(&data.identifier.value),
                         id.index
                     )?;
                 } else {
                     write!(
                         f, "Symbolic({}, id: Unresolved)",
                         String::from_utf8_lossy(&data.identifier.value)
                     )?;
+                }
+            }
+        }
         if self.array {
             write!(f, "[]")
         } else {
             Ok(())
+        }
+    }
+}
 type CharacterData = Vec<u8>;
 type IntegerData = i64;
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub enum Constant {
     Null, // message
     True,
     False,
     Character(CharacterData),
     Integer(IntegerData),
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub enum Method {
     Get,
     Fires,
     Create,
     Symbolic(MethodSymbolic)
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct MethodSymbolic {
     pub(crate) identifier: NamespacedIdentifier,
     pub(crate) definition: Option<DefinitionId>
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub enum Field {
     Length,
     Symbolic(Identifier),
+}
 impl Field {
     pub fn is_length(&self) -> bool {
         match self {
             Field::Length => true,
             _ => false,
+        }
+    }
+}
 #[derive(Debug, Clone, Copy, serde::Serialize, serde::Deserialize)]
 pub enum Scope {
     Definition(DefinitionId),
     Regular(BlockStatementId),
     Synchronous((SynchronousStatementId, BlockStatementId)),
+}
 impl Scope {
     pub fn is_block(&self) -> bool {
         match &self {
             Scope::Definition(_) => false,
             Scope::Regular(_) => true,
             Scope::Synchronous(_) => true,
+        }
+    }
     pub fn to_block(&self) -> BlockStatementId {
         match &self {
             Scope::Regular(id) => *id,
             Scope::Synchronous((_, id)) => *id,
             _ => panic!("unable to get BlockStatement from Scope")
+        }
+    }
+}
 pub trait VariableScope {
     fn parent_scope(&self, h: &Heap) -> Option<Scope>;
     fn get_variable(&self, h: &Heap, id: &Identifier) -> Option<VariableId>;
+}
 impl VariableScope for Scope {
     fn parent_scope(&self, h: &Heap) -> Option<Scope> {
         match self {
             Scope::Definition(def) => h[*def].parent_scope(h),
             Scope::Regular(stmt) => h[*stmt].parent_scope(h),
             Scope::Synchronous((stmt, _)) => h[*stmt].parent_scope(h),
+        }
+    }
     fn get_variable(&self, h: &Heap, id: &Identifier) -> Option<VariableId> {
         match self {
             Scope::Definition(def) => h[*def].get_variable(h, id),
             Scope::Regular(stmt) => h[*stmt].get_variable(h, id),
             Scope::Synchronous((stmt, _)) => h[*stmt].get_variable(h, id),
+        }
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub enum Variable {
     Parameter(Parameter),
     Local(Local),
+}
 impl Variable {
     pub fn identifier(&self) -> &Identifier {
         match self {
             Variable::Parameter(var) => &var.identifier,
             Variable::Local(var) => &var.identifier,
+        }
+    }
     pub fn is_parameter(&self) -> bool {
         match self {
             Variable::Parameter(_) => true,
             _ => false,
+        }
+    }
     pub fn as_parameter(&self) -> &Parameter {
         match self {
             Variable::Parameter(result) => result,
             _ => panic!("Unable to cast `Variable` to `Parameter`"),
+        }
+    }
     pub fn as_local(&self) -> &Local {
         match self {
             Variable::Local(result) => result,
             _ => panic!("Unable to cast `Variable` to `Local`"),
+        }
+    }
     pub fn as_local_mut(&mut self) -> &mut Local {
         match self {
             Variable::Local(result) => result,
             _ => panic!("Unable to cast 'Variable' to 'Local'"),
+        }
+    }
+}
 impl SyntaxElement for Variable {
     fn position(&self) -> InputPosition {
         match self {
             Variable::Parameter(decl) => decl.position(),
             Variable::Local(decl) => decl.position(),
+        }
+    }
+}
 /// TODO: Remove distinction between parameter/local and add an enum to indicate
 ///     the distinction between the two
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct Parameter {
     pub this: ParameterId,
     // Phase 1: parser
     pub position: InputPosition,
     pub parser_type: ParserTypeId,
     pub identifier: Identifier,
+}
 impl SyntaxElement for Parameter {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct Local {
     pub this: LocalId,
     // Phase 1: parser
     pub position: InputPosition,
     pub parser_type: ParserTypeId,
     pub identifier: Identifier,
     // Phase 2: linker
     pub relative_pos_in_block: u32,
+}
 impl SyntaxElement for Local {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub enum Definition {
     Struct(StructDefinition),
     Enum(EnumDefinition),
     Component(Component),
     Function(Function),
+}
 impl Definition {
     pub fn is_struct(&self) -> bool {
         match self {
             Definition::Struct(_) => true,
             _ => false
+        }
+    }
     pub fn as_struct(&self) -> &StructDefinition {
         match self {
             Definition::Struct(result) => result,
             _ => panic!("Unable to cast 'Definition' to 'StructDefinition'"),
+        }
+    }
     pub fn is_enum(&self) -> bool {
         match self {
             Definition::Enum(_) => true,
             _ => false,
+        }
+    }
     pub fn as_enum(&self) -> &EnumDefinition {
         match self {
             Definition::Enum(result) => result,
             _ => panic!("Unable to cast 'Definition' to 'EnumDefinition'"),
+        }
+    }
     pub fn is_component(&self) -> bool {
         match self {
             Definition::Component(_) => true,
             _ => false,
+        }
+    }
     pub fn as_component(&self) -> &Component {
         match self {
             Definition::Component(result) => result,
             _ => panic!("Unable to cast `Definition` to `Component`"),
+        }
+    }
     pub fn is_function(&self) -> bool {
         match self {
             Definition::Function(_) => true,
             _ => false,
+        }
+    }
     pub fn as_function(&self) -> &Function {
         match self {
             Definition::Function(result) => result,
             _ => panic!("Unable to cast `Definition` to `Function`"),
+        }
+    }
     pub fn identifier(&self) -> &Identifier {
         match self {
             Definition::Struct(def) => &def.identifier,
             Definition::Enum(def) => &def.identifier,
             Definition::Component(com) => &com.identifier,
             Definition::Function(fun) => &fun.identifier,
+        }
+    }
     pub fn parameters(&self) -> &Vec<ParameterId> {
         // TODO: Fix this
         static EMPTY_VEC: Vec<ParameterId> = Vec::new();
         match self {
             Definition::Component(com) => &com.parameters,
             Definition::Function(fun) => &fun.parameters,
             _ => &EMPTY_VEC,
+        }
+    }
     pub fn body(&self) -> StatementId {
         // TODO: Fix this
         match self {
             Definition::Component(com) => com.body,
             Definition::Function(fun) => fun.body,
             _ => panic!("cannot retrieve body (for EnumDefinition or StructDefinition)")
+        }
+    }
+}
 impl SyntaxElement for Definition {
     fn position(&self) -> InputPosition {
         match self {
             Definition::Struct(def) => def.position,
             Definition::Enum(def) => def.position,
             Definition::Component(def) => def.position(),
             Definition::Function(def) => def.position(),
+        }
+    }
+}
 impl VariableScope for Definition {
     fn parent_scope(&self, _h: &Heap) -> Option<Scope> {
         None
+    }
     fn get_variable(&self, h: &Heap, id: &Identifier) -> Option<VariableId> {
         for &parameter_id in self.parameters().iter() {
             let parameter = &h[parameter_id];
             if parameter.identifier.value == id.value {
                 return Some(parameter_id.0);
+            }
+        }
         None
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct StructFieldDefinition {
     pub position: InputPosition,
     pub field: Identifier,
     pub parser_type: ParserTypeId,
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct StructDefinition {
     pub this: StructId,
     // Phase 1: parser
     pub position: InputPosition,
     pub identifier: Identifier,
     pub poly_vars: Vec<Identifier>,
     pub fields: Vec<StructFieldDefinition>
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize, PartialEq)]
 pub enum EnumVariantValue {
     None,
     Integer(i64),
     Type(ParserTypeId),
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct EnumVariantDefinition {
     pub position: InputPosition,
     pub identifier: Identifier,
     pub value: EnumVariantValue,
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct EnumDefinition {
     pub this: EnumId,
     // Phase 1: parser
     pub position: InputPosition,
     pub identifier: Identifier,
     pub poly_vars: Vec<Identifier>,
     pub variants: Vec<EnumVariantDefinition>,
+}
 #[derive(Debug, Clone, Copy, serde::Serialize, serde::Deserialize)]
 pub enum ComponentVariant {
     Primitive,
     Composite,
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct Component {
     pub this: ComponentId,
     // Phase 1: parser
     pub position: InputPosition,
     pub variant: ComponentVariant,
     pub identifier: Identifier,
     pub poly_vars: Vec<Identifier>,
     pub parameters: Vec<ParameterId>,
     pub body: StatementId,
+}
 impl SyntaxElement for Component {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct Function {
     pub this: FunctionId,
     // Phase 1: parser
     pub position: InputPosition,
     pub return_type: ParserTypeId,
     pub identifier: Identifier,
     pub poly_vars: Vec<Identifier>,
     pub parameters: Vec<ParameterId>,
     pub body: StatementId,
+}
 impl SyntaxElement for Function {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub enum Statement {
     Block(BlockStatement),
     Local(LocalStatement),
     Skip(SkipStatement),
     Labeled(LabeledStatement),
     If(IfStatement),
     EndIf(EndIfStatement),
     While(WhileStatement),
     EndWhile(EndWhileStatement),
     Break(BreakStatement),
     Continue(ContinueStatement),
     Synchronous(SynchronousStatement),
     EndSynchronous(EndSynchronousStatement),
     Return(ReturnStatement),
     Assert(AssertStatement),
     Goto(GotoStatement),
     New(NewStatement),
     Put(PutStatement),
     Expression(ExpressionStatement),
+}
 impl Statement {
     pub fn as_block(&self) -> &BlockStatement {
         match self {
             Statement::Block(result) => result,
             _ => panic!("Unable to cast `Statement` to `BlockStatement`"),
+        }
+    }
     pub fn as_block_mut(&mut self) -> &mut BlockStatement {
         match self {
             Statement::Block(result) => result,
             _ => panic!("Unable to cast `Statement` to `BlockStatement`"),
+        }
+    }
     pub fn as_local(&self) -> &LocalStatement {
         match self {
             Statement::Local(result) => result,
             _ => panic!("Unable to cast `Statement` to `LocalStatement`"),
+        }
+    }
     pub fn as_memory(&self) -> &MemoryStatement {
         self.as_local().as_memory()
+    }
     pub fn as_channel(&self) -> &ChannelStatement {
         self.as_local().as_channel()
+    }
     pub fn as_skip(&self) -> &SkipStatement {
         match self {
             Statement::Skip(result) => result,
             _ => panic!("Unable to cast `Statement` to `SkipStatement`"),
+        }
+    }
     pub fn as_labeled(&self) -> &LabeledStatement {
         match self {
             Statement::Labeled(result) => result,
             _ => panic!("Unable to cast `Statement` to `LabeledStatement`"),
+        }
+    }
     pub fn as_labeled_mut(&mut self) -> &mut LabeledStatement {
         match self {
             Statement::Labeled(result) => result,
             _ => panic!("Unable to cast `Statement` to `LabeledStatement`"),
+        }
+    }
     pub fn as_if(&self) -> &IfStatement {
         match self {
             Statement::If(result) => result,
             _ => panic!("Unable to cast `Statement` to `IfStatement`"),
+        }
+    }
     pub fn as_if_mut(&mut self) -> &mut IfStatement {
         match self {
             Statement::If(result) => result,
             _ => panic!("Unable to cast 'Statement' to 'IfStatement'"),
+        }
+    }
     pub fn as_end_if(&self) -> &EndIfStatement {
         match self {
             Statement::EndIf(result) => result,
             _ => panic!("Unable to cast `Statement` to `EndIfStatement`"),
+        }
+    }
     pub fn is_while(&self) -> bool {
         match self {
             Statement::While(_) => true,
             _ => false,
+        }
+    }
     pub fn as_while(&self) -> &WhileStatement {
         match self {
             Statement::While(result) => result,
             _ => panic!("Unable to cast `Statement` to `WhileStatement`"),
+        }
+    }
     pub fn as_while_mut(&mut self) -> &mut WhileStatement {
         match self {
             Statement::While(result) => result,
             _ => panic!("Unable to cast `Statement` to `WhileStatement`"),
+        }
+    }
     pub fn as_end_while(&self) -> &EndWhileStatement {
         match self {
             Statement::EndWhile(result) => result,
             _ => panic!("Unable to cast `Statement` to `EndWhileStatement`"),
+        }
+    }
     pub fn as_break(&self) -> &BreakStatement {
         match self {
             Statement::Break(result) => result,
             _ => panic!("Unable to cast `Statement` to `BreakStatement`"),
+        }
+    }
     pub fn as_break_mut(&mut self) -> &mut BreakStatement {
         match self {
             Statement::Break(result) => result,
             _ => panic!("Unable to cast `Statement` to `BreakStatement`"),
+        }
+    }
     pub fn as_continue(&self) -> &ContinueStatement {
         match self {
             Statement::Continue(result) => result,
             _ => panic!("Unable to cast `Statement` to `ContinueStatement`"),
+        }
+    }
     pub fn as_continue_mut(&mut self) -> &mut ContinueStatement {
         match self {
             Statement::Continue(result) => result,
             _ => panic!("Unable to cast `Statement` to `ContinueStatement`"),
+        }
+    }
     pub fn as_synchronous(&self) -> &SynchronousStatement {
         match self {
             Statement::Synchronous(result) => result,
             _ => panic!("Unable to cast `Statement` to `SynchronousStatement`"),
+        }
+    }
     pub fn as_synchronous_mut(&mut self) -> &mut SynchronousStatement {
         match self {
             Statement::Synchronous(result) => result,
             _ => panic!("Unable to cast `Statement` to `SynchronousStatement`"),
+        }
+    }
     pub fn as_end_synchronous(&self) -> &EndSynchronousStatement {
         match self {
             Statement::EndSynchronous(result) => result,
             _ => panic!("Unable to cast `Statement` to `EndSynchronousStatement`"),
+        }
+    }
     pub fn as_return(&self) -> &ReturnStatement {
         match self {
             Statement::Return(result) => result,
             _ => panic!("Unable to cast `Statement` to `ReturnStatement`"),
+        }
+    }
     pub fn as_assert(&self) -> &AssertStatement {
         match self {
             Statement::Assert(result) => result,
             _ => panic!("Unable to cast `Statement` to `AssertStatement`"),
+        }
+    }
     pub fn as_goto(&self) -> &GotoStatement {
         match self {
             Statement::Goto(result) => result,
             _ => panic!("Unable to cast `Statement` to `GotoStatement`"),
+        }
+    }
     pub fn as_goto_mut(&mut self) -> &mut GotoStatement {
         match self {
             Statement::Goto(result) => result,
             _ => panic!("Unable to cast `Statement` to `GotoStatement`"),
+        }
+    }
     pub fn as_new(&self) -> &NewStatement {
         match self {
             Statement::New(result) => result,
             _ => panic!("Unable to cast `Statement` to `NewStatement`"),
+        }
+    }
     pub fn as_put(&self) -> &PutStatement {
         match self {
             Statement::Put(result) => result,
             _ => panic!("Unable to cast `Statement` to `PutStatement`"),
+        }
+    }
     pub fn as_expression(&self) -> &ExpressionStatement {
         match self {
             Statement::Expression(result) => result,
             _ => panic!("Unable to cast `Statement` to `ExpressionStatement`"),
+        }
+    }
     pub fn link_next(&mut self, next: StatementId) {
         match self {
             Statement::Block(_) => todo!(),
             Statement::Local(stmt) => match stmt {
                 LocalStatement::Channel(stmt) => stmt.next = Some(next),
                 LocalStatement::Memory(stmt) => stmt.next = Some(next),
             },
             Statement::Skip(stmt) => stmt.next = Some(next),
             Statement::EndIf(stmt) => stmt.next = Some(next),
             Statement::EndWhile(stmt) => stmt.next = Some(next),
             Statement::EndSynchronous(stmt) => stmt.next = Some(next),
             Statement::Assert(stmt) => stmt.next = Some(next),
             Statement::New(stmt) => stmt.next = Some(next),
             Statement::Put(stmt) => stmt.next = Some(next),
             Statement::Expression(stmt) => stmt.next = Some(next),
             Statement::Return(_)
             | Statement::Break(_)
             | Statement::Continue(_)
             | Statement::Synchronous(_)
             | Statement::Goto(_)
             | Statement::While(_)
             | Statement::Labeled(_)
             | Statement::If(_) => unreachable!(),
+        }
+    }
+}
 impl SyntaxElement for Statement {
     fn position(&self) -> InputPosition {
         match self {
             Statement::Block(stmt) => stmt.position(),
             Statement::Local(stmt) => stmt.position(),
             Statement::Skip(stmt) => stmt.position(),
             Statement::Labeled(stmt) => stmt.position(),
             Statement::If(stmt) => stmt.position(),
             Statement::EndIf(stmt) => stmt.position(),
             Statement::While(stmt) => stmt.position(),
             Statement::EndWhile(stmt) => stmt.position(),
             Statement::Break(stmt) => stmt.position(),
             Statement::Continue(stmt) => stmt.position(),
             Statement::Synchronous(stmt) => stmt.position(),
             Statement::EndSynchronous(stmt) => stmt.position(),
             Statement::Return(stmt) => stmt.position(),
             Statement::Assert(stmt) => stmt.position(),
             Statement::Goto(stmt) => stmt.position(),
             Statement::New(stmt) => stmt.position(),
             Statement::Put(stmt) => stmt.position(),
             Statement::Expression(stmt) => stmt.position(),
+        }
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct BlockStatement {
     pub this: BlockStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub statements: Vec<StatementId>,
     // Phase 2: linker
     pub parent_scope: Option<Scope>,
     pub relative_pos_in_parent: u32,
     pub locals: Vec<LocalId>,
     pub labels: Vec<LabeledStatementId>,
+}
 impl BlockStatement {
     pub fn parent_block(&self, h: &Heap) -> Option<BlockStatementId> {
         let parent = self.parent_scope.unwrap();
         match parent {
             Scope::Definition(_) => {
                 // If the parent scope is a definition, then there is no
                 // parent block.
                 None
+            }
             Scope::Synchronous((parent, _)) => {
                 // It is always the case that when this function is called,
                 // the parent of a synchronous statement is a block statement:
                 // nested synchronous statements are flagged illegal,
                 // and that happens before resolving variables that
                 // creates the parent_scope references in the first place.
                 Some(h[parent].parent_scope(h).unwrap().to_block())
+            }
             Scope::Regular(parent) => {
                 // A variable scope is either a definition, sync, or block.
                 Some(parent)
+            }
+        }
+    }
     pub fn first(&self) -> StatementId {
         // It is an invariant (guaranteed by the lexer) that block statements have at least one stmt
         *self.statements.first().unwrap()
+    }
+}
 impl SyntaxElement for BlockStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 impl VariableScope for BlockStatement {
     fn parent_scope(&self, _h: &Heap) -> Option<Scope> {
         self.parent_scope.clone()
+    }
     fn get_variable(&self, h: &Heap, id: &Identifier) -> Option<VariableId> {
         for local_id in self.locals.iter() {
             let local = &h[*local_id];
             if local.identifier.value == id.value {
                 return Some(local_id.0);
+            }
+        }
         None
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub enum LocalStatement {
     Memory(MemoryStatement),
     Channel(ChannelStatement),
+}
 impl LocalStatement {
     pub fn this(&self) -> LocalStatementId {
         match self {
             LocalStatement::Memory(stmt) => stmt.this.upcast(),
             LocalStatement::Channel(stmt) => stmt.this.upcast(),
+        }
+    }
     pub fn as_memory(&self) -> &MemoryStatement {
         match self {
             LocalStatement::Memory(result) => result,
             _ => panic!("Unable to cast `LocalStatement` to `MemoryStatement`"),
+        }
+    }
     pub fn as_channel(&self) -> &ChannelStatement {
         match self {
             LocalStatement::Channel(result) => result,
             _ => panic!("Unable to cast `LocalStatement` to `ChannelStatement`"),
+        }
+    }
     pub fn next(&self) -> Option<StatementId> {
         match self {
             LocalStatement::Memory(stmt) => stmt.next,
             LocalStatement::Channel(stmt) => stmt.next,
+        }
+    }
+}
 impl SyntaxElement for LocalStatement {
     fn position(&self) -> InputPosition {
         match self {
             LocalStatement::Memory(stmt) => stmt.position(),
             LocalStatement::Channel(stmt) => stmt.position(),
+        }
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct MemoryStatement {
     pub this: MemoryStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub variable: LocalId,
     pub initial: ExpressionId,
     // Phase 2: linker
     pub next: Option<StatementId>,
+}
 impl SyntaxElement for MemoryStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 /// ChannelStatement is the declaration of an input and output port associated
 /// with the same channel. Note that the polarity of the ports are from the
 /// point of view of the component. So an output port is something that a
 /// component uses to send data over (i.e. it is the "input end" of the
 /// channel), and vice versa.
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct ChannelStatement {
     pub this: ChannelStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub from: LocalId, // output
     pub to: LocalId,   // input
     // Phase 2: linker
     pub relative_pos_in_block: u32,
     pub next: Option<StatementId>,
+}
 impl SyntaxElement for ChannelStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct SkipStatement {
     pub this: SkipStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     // Phase 2: linker
     pub next: Option<StatementId>,
+}
 impl SyntaxElement for SkipStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct LabeledStatement {
     pub this: LabeledStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub label: Identifier,
     pub body: StatementId,
     // Phase 2: linker
     pub relative_pos_in_block: u32,
     pub in_sync: Option<SynchronousStatementId>,
+}
 impl SyntaxElement for LabeledStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct IfStatement {
     pub this: IfStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub test: ExpressionId,
     pub true_body: StatementId,
     pub false_body: StatementId,
     // Phase 2: linker
     pub end_if: Option<EndIfStatementId>,
+}
 impl SyntaxElement for IfStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct EndIfStatement {
     pub this: EndIfStatementId,
     // Phase 2: linker
     pub start_if: IfStatementId,
     pub position: InputPosition, // of corresponding if statement
     pub next: Option<StatementId>,
+}
 impl SyntaxElement for EndIfStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct WhileStatement {
     pub this: WhileStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub test: ExpressionId,
     pub body: StatementId,
     // Phase 2: linker
     pub end_while: Option<EndWhileStatementId>,
     pub in_sync: Option<SynchronousStatementId>,
+}
 impl SyntaxElement for WhileStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct EndWhileStatement {
     pub this: EndWhileStatementId,
     // Phase 2: linker
     pub start_while: WhileStatementId,
     pub position: InputPosition, // of corresponding while
     pub next: Option<StatementId>,
+}
 impl SyntaxElement for EndWhileStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct BreakStatement {
     pub this: BreakStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub label: Option<Identifier>,
     // Phase 2: linker
     pub target: Option<EndWhileStatementId>,
+}
 impl SyntaxElement for BreakStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct ContinueStatement {
     pub this: ContinueStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub label: Option<Identifier>,
     // Phase 2: linker
     pub target: Option<WhileStatementId>,
+}
 impl SyntaxElement for ContinueStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct SynchronousStatement {
     pub this: SynchronousStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     // pub parameters: Vec<ParameterId>,
     pub body: StatementId,
     // Phase 2: linker
     pub end_sync: Option<EndSynchronousStatementId>,
     pub parent_scope: Option<Scope>,
+}
 impl SyntaxElement for SynchronousStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 impl VariableScope for SynchronousStatement {
     fn parent_scope(&self, _h: &Heap) -> Option<Scope> {
         self.parent_scope.clone()
+    }
     fn get_variable(&self, _h: &Heap, _id: &Identifier) -> Option<VariableId> {
         // TODO: Another case of "where was this used for?"
         // for parameter_id in self.parameters.iter() {
         //     let parameter = &h[*parameter_id];
         //     if parameter.identifier.value == id.value {
         //         return Some(parameter_id.0);
         //     }
         // }
         None
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct EndSynchronousStatement {
     pub this: EndSynchronousStatementId,
     // Phase 2: linker
     pub position: InputPosition, // of corresponding sync statement
     pub start_sync: SynchronousStatementId,
     pub next: Option<StatementId>,
+}
 impl SyntaxElement for EndSynchronousStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct ReturnStatement {
     pub this: ReturnStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub expression: ExpressionId,
+}
 impl SyntaxElement for ReturnStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct AssertStatement {
     pub this: AssertStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub expression: ExpressionId,
     // Phase 2: linker
     pub next: Option<StatementId>,
+}
 impl SyntaxElement for AssertStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct GotoStatement {
     pub this: GotoStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub label: Identifier,
     // Phase 2: linker
     pub target: Option<LabeledStatementId>,
+}
 impl SyntaxElement for GotoStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct NewStatement {
     pub this: NewStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub expression: CallExpressionId,
     // Phase 2: linker
     pub next: Option<StatementId>,
+}
 impl SyntaxElement for NewStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct PutStatement {
     pub this: PutStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub port: ExpressionId,
     pub message: ExpressionId,
     // Phase 2: linker
     pub next: Option<StatementId>,
+}
 impl SyntaxElement for PutStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct ExpressionStatement {
     pub this: ExpressionStatementId,
     // Phase 1: parser
     pub position: InputPosition,
     pub expression: ExpressionId,
     // Phase 2: linker
     pub next: Option<StatementId>,
+}
 impl SyntaxElement for ExpressionStatement {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, PartialEq, Eq, Clone, Copy, serde::Serialize, serde::Deserialize)]
 pub enum ExpressionParent {
     None, // only set during initial parsing
     Memory(MemoryStatementId),
     If(IfStatementId),
     While(WhileStatementId),
     Return(ReturnStatementId),
     Assert(AssertStatementId),
     New(NewStatementId),
     Put(PutStatementId, u32), // index of arg
     ExpressionStmt(ExpressionStatementId),
     Expression(ExpressionId, u32) // index within expression (e.g LHS or RHS of expression)
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub enum Expression {
     Assignment(AssignmentExpression),
     Conditional(ConditionalExpression),
     Binary(BinaryExpression),
     Unary(UnaryExpression),
     Indexing(IndexingExpression),
     Slicing(SlicingExpression),
     Select(SelectExpression),
     Array(ArrayExpression),
     Constant(ConstantExpression),
     Call(CallExpression),
     Variable(VariableExpression),
+}
 impl Expression {
     pub fn as_assignment(&self) -> &AssignmentExpression {
         match self {
             Expression::Assignment(result) => result,
             _ => panic!("Unable to cast `Expression` to `AssignmentExpression`"),
+        }
+    }
     pub fn as_conditional(&self) -> &ConditionalExpression {
         match self {
             Expression::Conditional(result) => result,
             _ => panic!("Unable to cast `Expression` to `ConditionalExpression`"),
+        }
+    }
     pub fn as_binary(&self) -> &BinaryExpression {
         match self {
             Expression::Binary(result) => result,
             _ => panic!("Unable to cast `Expression` to `BinaryExpression`"),
+        }
+    }
     pub fn as_unary(&self) -> &UnaryExpression {
         match self {
             Expression::Unary(result) => result,
             _ => panic!("Unable to cast `Expression` to `UnaryExpression`"),
+        }
+    }
     pub fn as_indexing(&self) -> &IndexingExpression {
         match self {
             Expression::Indexing(result) => result,
             _ => panic!("Unable to cast `Expression` to `IndexingExpression`"),
+        }
+    }
     pub fn as_slicing(&self) -> &SlicingExpression {
         match self {
             Expression::Slicing(result) => result,
             _ => panic!("Unable to cast `Expression` to `SlicingExpression`"),
+        }
+    }
     pub fn as_select(&self) -> &SelectExpression {
         match self {
             Expression::Select(result) => result,
             _ => panic!("Unable to cast `Expression` to `SelectExpression`"),
+        }
+    }
     pub fn as_array(&self) -> &ArrayExpression {
         match self {
             Expression::Array(result) => result,
             _ => panic!("Unable to cast `Expression` to `ArrayExpression`"),
+        }
+    }
     pub fn as_constant(&self) -> &ConstantExpression {
         match self {
             Expression::Constant(result) => result,
             _ => panic!("Unable to cast `Expression` to `ConstantExpression`"),
+        }
+    }
     pub fn as_call(&self) -> &CallExpression {
         match self {
             Expression::Call(result) => result,
             _ => panic!("Unable to cast `Expression` to `CallExpression`"),
+        }
+    }
     pub fn as_call_mut(&mut self) -> &mut CallExpression {
         match self {
             Expression::Call(result) => result,
             _ => panic!("Unable to cast `Expression` to `CallExpression`"),
+        }
+    }
     pub fn as_variable(&self) -> &VariableExpression {
         match self {
             Expression::Variable(result) => result,
             _ => panic!("Unable to cast `Expression` to `VariableExpression`"),
+        }
+    }
     pub fn as_variable_mut(&mut self) -> &mut VariableExpression {
         match self {
             Expression::Variable(result) => result,
             _ => panic!("Unable to cast `Expression` to `VariableExpression`"),
+        }
+    }
     // TODO: @cleanup
     pub fn parent(&self) -> &ExpressionParent {
         match self {
             Expression::Assignment(expr) => &expr.parent,
             Expression::Conditional(expr) => &expr.parent,
             Expression::Binary(expr) => &expr.parent,
             Expression::Unary(expr) => &expr.parent,
             Expression::Indexing(expr) => &expr.parent,
             Expression::Slicing(expr) => &expr.parent,
             Expression::Select(expr) => &expr.parent,
             Expression::Array(expr) => &expr.parent,
             Expression::Constant(expr) => &expr.parent,
             Expression::Call(expr) => &expr.parent,
             Expression::Variable(expr) => &expr.parent,
+        }
+    }
     pub fn set_parent(&mut self, parent: ExpressionParent) {
         match self {
             Expression::Assignment(expr) => expr.parent = parent,
             Expression::Conditional(expr) => expr.parent = parent,
             Expression::Binary(expr) => expr.parent = parent,
             Expression::Unary(expr) => expr.parent = parent,
             Expression::Indexing(expr) => expr.parent = parent,
             Expression::Slicing(expr) => expr.parent = parent,
             Expression::Select(expr) => expr.parent = parent,
             Expression::Array(expr) => expr.parent = parent,
             Expression::Constant(expr) => expr.parent = parent,
             Expression::Call(expr) => expr.parent = parent,
             Expression::Variable(expr) => expr.parent = parent,
+        }
+    }
+}
 impl SyntaxElement for Expression {
     fn position(&self) -> InputPosition {
         match self {
             Expression::Assignment(expr) => expr.position(),
             Expression::Conditional(expr) => expr.position(),
             Expression::Binary(expr) => expr.position(),
             Expression::Unary(expr) => expr.position(),
             Expression::Indexing(expr) => expr.position(),
             Expression::Slicing(expr) => expr.position(),
             Expression::Select(expr) => expr.position(),
             Expression::Array(expr) => expr.position(),
             Expression::Constant(expr) => expr.position(),
             Expression::Call(expr) => expr.position(),
             Expression::Variable(expr) => expr.position(),
+        }
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub enum AssignmentOperator {
     Set,
     Multiplied,
     Divided,
     Remained,
     Added,
     Subtracted,
     ShiftedLeft,
     ShiftedRight,
     BitwiseAnded,
     BitwiseXored,
     BitwiseOred,
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct AssignmentExpression {
     pub this: AssignmentExpressionId,
     // Phase 1: parser
     pub position: InputPosition,
     pub left: ExpressionId,
     pub operation: AssignmentOperator,
     pub right: ExpressionId,
     // Phase 2: linker
     pub parent: ExpressionParent,
+}
 impl SyntaxElement for AssignmentExpression {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct ConditionalExpression {
     pub this: ConditionalExpressionId,
     // Phase 1: parser
     pub position: InputPosition,
     pub test: ExpressionId,
     pub true_expression: ExpressionId,
     pub false_expression: ExpressionId,
     // Phase 2: linker
     pub parent: ExpressionParent,
+}
 impl SyntaxElement for ConditionalExpression {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
 pub enum BinaryOperator {
     Concatenate,
     LogicalOr,
     LogicalAnd,
     BitwiseOr,
     BitwiseXor,
     BitwiseAnd,
     Equality,
     Inequality,
     LessThan,
     GreaterThan,
     LessThanEqual,
     GreaterThanEqual,
     ShiftLeft,
     ShiftRight,
     Add,
     Subtract,
     Multiply,
     Divide,
     Remainder,
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct BinaryExpression {
     pub this: BinaryExpressionId,
     // Phase 1: parser
     pub position: InputPosition,
     pub left: ExpressionId,
     pub operation: BinaryOperator,
     pub right: ExpressionId,
     // Phase 2: linker
     pub parent: ExpressionParent,
+}
 impl SyntaxElement for BinaryExpression {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
 pub enum UnaryOperation {
     Positive,
     Negative,
     BitwiseNot,
     LogicalNot,
     PreIncrement,
     PreDecrement,
     PostIncrement,
     PostDecrement,
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct UnaryExpression {
     pub this: UnaryExpressionId,
     // Phase 1: parser
     pub position: InputPosition,
     pub operation: UnaryOperation,
     pub expression: ExpressionId,
     // Phase 2: linker
     pub parent: ExpressionParent,
+}
 impl SyntaxElement for UnaryExpression {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct IndexingExpression {
     pub this: IndexingExpressionId,
     // Phase 1: parser
     pub position: InputPosition,
     pub subject: ExpressionId,
     pub index: ExpressionId,
     // Phase 2: linker
     pub parent: ExpressionParent,
+}
 impl SyntaxElement for IndexingExpression {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct SlicingExpression {
     pub this: SlicingExpressionId,
     // Phase 1: parser
     pub position: InputPosition,
     pub subject: ExpressionId,
     pub from_index: ExpressionId,
     pub to_index: ExpressionId,
     // Phase 2: linker
     pub parent: ExpressionParent,
+}
 impl SyntaxElement for SlicingExpression {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct SelectExpression {
     pub this: SelectExpressionId,
     // Phase 1: parser
     pub position: InputPosition,
     pub subject: ExpressionId,
     pub field: Field,
     // Phase 2: linker
     pub parent: ExpressionParent,
+}
 impl SyntaxElement for SelectExpression {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct ArrayExpression {
     pub this: ArrayExpressionId,
     // Phase 1: parser
     pub position: InputPosition,
     pub elements: Vec<ExpressionId>,
     // Phase 2: linker
     pub parent: ExpressionParent,
+}
 impl SyntaxElement for ArrayExpression {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct CallExpression {
     pub this: CallExpressionId,
     // Phase 1: parser
     pub position: InputPosition,
     pub method: Method,
     pub arguments: Vec<ExpressionId>,
     pub poly_args: Vec<ParserTypeId>,
     // Phase 2: linker
     pub parent: ExpressionParent,
+}
 impl SyntaxElement for CallExpression {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct ConstantExpression {
     pub this: ConstantExpressionId,
     // Phase 1: parser
     pub position: InputPosition,
     pub value: Constant,
     // Phase 2: linker
     pub parent: ExpressionParent,
+}
 impl SyntaxElement for ConstantExpression {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 pub struct VariableExpression {
     pub this: VariableExpressionId,
     // Phase 1: parser
     pub position: InputPosition,
     pub identifier: NamespacedIdentifier,
     // Phase 2: linker
     pub declaration: Option<VariableId>,
     pub parent: ExpressionParent,
+}
 impl SyntaxElement for VariableExpression {
     fn position(&self) -> InputPosition {
         self.position
+    }
+}

src/protocol/lexer.rs

➞

Show inline comments

 use crate::protocol::ast::*;
 use crate::protocol::inputsource::*;
 const MAX_LEVEL: usize = 128;
 const MAX_NAMESPACES: u8 = 8; // only three levels are supported at the moment
 fn is_vchar(x: Option<u8>) -> bool {
     if let Some(c) = x {
         c >= 0x21 && c <= 0x7E
     } else {
         false
+    }
+}
 fn is_wsp(x: Option<u8>) -> bool {
     if let Some(c) = x {
         c == b' ' || c == b'\t'
     } else {
         false
+    }
+}
 fn is_ident_start(x: Option<u8>) -> bool {
     if let Some(c) = x {
         c >= b'A' && c <= b'Z' || c >= b'a' && c <= b'z'
     } else {
         false
+    }
+}
 fn is_ident_rest(x: Option<u8>) -> bool {
     if let Some(c) = x {
         c >= b'A' && c <= b'Z' || c >= b'a' && c <= b'z' || c >= b'0' && c <= b'9' || c == b'_'
     } else {
         false
+    }
+}
 fn is_constant(x: Option<u8>) -> bool {
     if let Some(c) = x {
         c >= b'0' && c <= b'9' || c == b'\''
     } else {
         false
+    }
+}
 fn is_integer_start(x: Option<u8>) -> bool {
     if let Some(c) = x {
         c >= b'0' && c <= b'9'
     } else {
         false
+    }
+}
 fn is_integer_rest(x: Option<u8>) -> bool {
     if let Some(c) = x {
         c >= b'0' && c <= b'9'
             || c >= b'a' && c <= b'f'
             || c >= b'A' && c <= b'F'
             || c == b'x'
             || c == b'o'
     } else {
         false
+    }
+}
 fn lowercase(x: u8) -> u8 {
     if x >= b'A' && x <= b'Z' {
         x - b'A' + b'a'
     } else {
+        x
+    }
+}
 pub struct Lexer<'a> {
     source: &'a mut InputSource,
     level: usize,
+}
 impl Lexer<'_> {
     pub fn new(source: &mut InputSource) -> Lexer {
         Lexer { source, level: 0 }
+    }
     fn error_at_pos(&self, msg: &str) -> ParseError2 {
         ParseError2::new_error(self.source, self.source.pos(), msg)
+    }
     fn consume_line(&mut self) -> Result<Vec<u8>, ParseError2> {
         let mut result: Vec<u8> = Vec::new();
         let mut next = self.source.next();
         while next.is_some() && next != Some(b'\n') && next != Some(b'\r') {
             if !(is_vchar(next) || is_wsp(next)) {
                 return Err(self.error_at_pos("Expected visible character or whitespace"));
+            }
             result.push(next.unwrap());
             self.source.consume();
             next = self.source.next();
+        }
         if next.is_some() {
             self.source.consume();
+        }
         if next == Some(b'\r') && self.source.next() == Some(b'\n') {
             self.source.consume();
+        }
         Ok(result)
+    }
     fn consume_whitespace(&mut self, expected: bool) -> Result<(), ParseError2> {
         let mut found = false;
         let mut next = self.source.next();
         while next.is_some() {
             if next == Some(b' ')
                 || next == Some(b'\t')
                 || next == Some(b'\r')
                 || next == Some(b'\n')
+            {
                 self.source.consume();
                 next = self.source.next();
                 found = true;
                 continue;
+            }
             if next == Some(b'/') {
                 next = self.source.lookahead(1);
                 if next == Some(b'/') {
                     self.source.consume(); // slash
                     self.source.consume(); // slash
                     self.consume_line()?;
                     next = self.source.next();
                     found = true;
                     continue;
+                }
                 if next == Some(b'*') {
                     self.source.consume(); // slash
                     self.source.consume(); // star
                     next = self.source.next();
                     while next.is_some() {
                         if next == Some(b'*') {
                             next = self.source.lookahead(1);
                             if next == Some(b'/') {
                                 self.source.consume(); // star
                                 self.source.consume(); // slash
                                 break;
+                            }
+                        }
                         self.source.consume();
                         next = self.source.next();
+                    }
                     next = self.source.next();
                     found = true;
                     continue;
+                }
+            }
             break;
+        }
         if expected && !found {
             Err(self.error_at_pos("Expected whitespace"))
         } else {
             Ok(())
+        }
+    }
     fn consume_any_chars(&mut self) {
         if !is_ident_start(self.source.next()) { return }
         self.source.consume();
         while is_ident_rest(self.source.next()) {
             self.source.consume()
+        }
+    }
     fn has_keyword(&self, keyword: &[u8]) -> bool {
         if !self.source.has(keyword) {
             return false;
+        }
         // Word boundary
         if let Some(next) = self.source.lookahead(keyword.len()) {
             !(next >= b'A' && next <= b'Z' || next >= b'a' && next <= b'z')
         } else {
             true
+        }
+    }
     fn consume_keyword(&mut self, keyword: &[u8]) -> Result<(), ParseError2> {
         let len = keyword.len();
         for i in 0..len {
             let expected = Some(lowercase(keyword[i]));
             let next = self.source.next();
             if next != expected {
                 return Err(self.error_at_pos(&format!("Expected keyword '{}'", String::from_utf8_lossy(keyword))));
+            }
             self.source.consume();
+        }
         if let Some(next) = self.source.next() {
             if next >= b'A' && next <= b'Z' || next >= b'a' && next <= b'z' || next >= b'0' && next <= b'9' {
                 return Err(self.error_at_pos(&format!("Expected word boundary after '{}'", String::from_utf8_lossy(keyword))));
+            }
+        }
         Ok(())
+    }
     fn has_string(&self, string: &[u8]) -> bool {
         self.source.has(string)
+    }
     fn consume_string(&mut self, string: &[u8]) -> Result<(), ParseError2> {
         let len = string.len();
         for i in 0..len {
             let expected = Some(string[i]);
             let next = self.source.next();
             if next != expected {
                 return Err(self.error_at_pos(&format!("Expected {}", String::from_utf8_lossy(string))));
+            }
             self.source.consume();
+        }
         Ok(())
+    }
     fn consume_ident(&mut self) -> Result<Vec<u8>, ParseError2> {
         if !self.has_identifier() {
             return Err(self.error_at_pos("Expected identifier"));
+        }
         let mut result = Vec::new();
         let mut next = self.source.next();
         result.push(next.unwrap());
         self.source.consume();
         next = self.source.next();
         while is_ident_rest(next) {
             result.push(next.unwrap());
             self.source.consume();
             next = self.source.next();
+        }
         Ok(result)
+    }
     fn has_integer(&mut self) -> bool {
         is_integer_start(self.source.next())
+    }
     fn consume_integer(&mut self) -> Result<i64, ParseError2> {
         let position = self.source.pos();
         let mut data = Vec::new();
         let mut next = self.source.next();
         while is_integer_rest(next) {
             data.push(next.unwrap());
             self.source.consume();
             next = self.source.next();
+        }
         let data_len = data.len();
         debug_assert_ne!(data_len, 0);
         if data_len == 1 {
             debug_assert!(data[0] >= b'0' && data[0] <= b'9');
             return Ok((data[0] - b'0') as i64);
         } else {
             // TODO: Fix, u64 should be supported as well
             let parsed = if data[1] == b'b' {
                 let data = String::from_utf8_lossy(&data[2..]);
                 i64::from_str_radix(&data, 2)
             } else if data[1] == b'o' {
                 let data = String::from_utf8_lossy(&data[2..]);
                 i64::from_str_radix(&data, 8)
             } else if data[1] == b'x' {
                 let data = String::from_utf8_lossy(&data[2..]);
                 i64::from_str_radix(&data, 16)
             } else {
                 // Assume decimal
                 let data = String::from_utf8_lossy(&data);
                 i64::from_str_radix(&data, 10)
             };
             if let Err(_err) = parsed {
                 return Err(ParseError2::new_error(&self.source, position, "Invalid integer constant"));
+            }
             Ok(parsed.unwrap())
+        }
+    }
     // Statement keywords
     // TODO: Clean up these functions
     fn has_statement_keyword(&self) -> bool {
         self.has_keyword(b"channel")
             || self.has_keyword(b"skip")
             || self.has_keyword(b"if")
             || self.has_keyword(b"while")
             || self.has_keyword(b"break")
             || self.has_keyword(b"continue")
             || self.has_keyword(b"synchronous")
             || self.has_keyword(b"return")
             || self.has_keyword(b"assert")
             || self.has_keyword(b"goto")
             || self.has_keyword(b"new")
             || self.has_keyword(b"put") // TODO: @fix, should be a function, even though it has sideeffects
+    }
     fn has_type_keyword(&self) -> bool {
         self.has_keyword(b"in")
             || self.has_keyword(b"out")
             || self.has_keyword(b"msg")
             || self.has_keyword(b"boolean")
             || self.has_keyword(b"byte")
             || self.has_keyword(b"short")
             || self.has_keyword(b"int")
             || self.has_keyword(b"long")
             || self.has_keyword(b"auto")
+    }
     fn has_builtin_keyword(&self) -> bool {
         self.has_keyword(b"get")
             || self.has_keyword(b"fires")
             || self.has_keyword(b"create")
             || self.has_keyword(b"length")
+    }
     fn has_reserved(&self) -> bool {
         self.has_statement_keyword()
             || self.has_type_keyword()
             || self.has_builtin_keyword()
             || self.has_keyword(b"let")
             || self.has_keyword(b"struct")
             || self.has_keyword(b"enum")
             || self.has_keyword(b"true")
             || self.has_keyword(b"false")
             || self.has_keyword(b"null")
+    }
     // Identifiers
     fn has_identifier(&self) -> bool {
         if self.has_statement_keyword() || self.has_type_keyword() || self.has_builtin_keyword() {
             return false;
+        }
         let next = self.source.next();
         is_ident_start(next)
+    }
     fn consume_identifier(&mut self) -> Result<Identifier, ParseError2> {
         if self.has_statement_keyword() || self.has_type_keyword() || self.has_builtin_keyword() {
             return Err(self.error_at_pos("Expected identifier"));
+        }
         let position = self.source.pos();
         let value = self.consume_ident()?;
         Ok(Identifier{ position, value })
+    }
     fn consume_identifier_spilled(&mut self) -> Result<(), ParseError2> {
         if self.has_statement_keyword() || self.has_type_keyword() || self.has_builtin_keyword() {
             return Err(self.error_at_pos("Expected identifier"));
+        }
         self.consume_ident()?;
         Ok(())
+    }
     fn has_namespaced_identifier(&self) -> bool {
         self.has_identifier()
+    }
     fn consume_namespaced_identifier(&mut self) -> Result<NamespacedIdentifier, ParseError2> {
         if self.has_reserved() {
             return Err(self.error_at_pos("Encountered reserved keyword"));
+        }
         let position = self.source.pos();
         let mut ns_ident = self.consume_ident()?;
         let mut num_namespaces = 1;
         while self.has_string(b"::") {
             self.consume_string(b"::");
             if num_namespaces >= MAX_NAMESPACES {
                 return Err(self.error_at_pos("Too many namespaces in identifier"));
+            }
             let new_ident = self.consume_ident()?;
             ns_ident.extend(b"::");
             ns_ident.extend(new_ident);
             num_namespaces += 1;
+        }
         Ok(NamespacedIdentifier{
             position,
             value: ns_ident,
             num_namespaces,
         })
+    }
     fn consume_namespaced_identifier_spilled(&mut self) -> Result<(), ParseError2> {
         // TODO: @performance
         if self.has_reserved() {
             return Err(self.error_at_pos("Encountered reserved keyword"));
+        }
         self.consume_ident()?;
         while self.has_string(b"::") {
             self.consume_string(b"::")?;
             self.consume_ident()?;
+        }
         Ok(())
+    }
     // Types and type annotations
     /// Consumes a type definition. When called the input position should be at
     /// the type specification. When done the input position will be at the end
     /// of the type specifications (hence may be at whitespace).
     fn consume_type2(&mut self, h: &mut Heap, allow_inference: bool) -> Result<ParserTypeId, ParseError2> {
         // Small helper function to convert in/out polymorphic arguments. Not
         // pretty, but return boolean is true if the error is due to inference
         // not being allowed
         let reduce_port_poly_args = |
             heap: &mut Heap,
             port_pos: &InputPosition,
             args: Vec<ParserTypeId>,
         | -> Result<ParserTypeId, bool> {
             match args.len() {
 => if allow_inference {
                     Ok(heap.alloc_parser_type(|this| ParserType{
                         this,
                         pos: port_pos.clone(),
                         variant: ParserTypeVariant::Inferred
                     }))
                 } else {
                     Err(true)
                 },
 => Ok(args[0]),
                 _ => Err(false)
+            }
         };
         // Consume the type
         let pos = self.source.pos();
         let parser_type_variant = if self.has_keyword(b"msg") {
             self.consume_keyword(b"msg")?;
             ParserTypeVariant::Message
         } else if self.has_keyword(b"boolean") {
             self.consume_keyword(b"boolean")?;
             ParserTypeVariant::Bool
         } else if self.has_keyword(b"byte") {
             self.consume_keyword(b"byte")?;
             ParserTypeVariant::Byte
         } else if self.has_keyword(b"short") {
             self.consume_keyword(b"short")?;
             ParserTypeVariant::Short
         } else if self.has_keyword(b"int") {
             self.consume_keyword(b"int")?;
             ParserTypeVariant::Int
         } else if self.has_keyword(b"long") {
             self.consume_keyword(b"long")?;
             ParserTypeVariant::Long
         } else if self.has_keyword(b"str") {
             self.consume_keyword(b"str")?;
             ParserTypeVariant::String
         } else if self.has_keyword(b"auto") {
             if !allow_inference {
                 return Err(ParseError2::new_error(
                         &self.source, pos,
                         "Type inference is not allowed here"
                 ));
+            }
             self.consume_keyword(b"auto")?;
             ParserTypeVariant::Inferred
         } else if self.has_keyword(b"in") {
             // TODO: @cleanup: not particularly neat to have this special case
             //  where we enforce polyargs in the parser-phase
             // TODO: @hack, temporarily allow inferred port values
             self.consume_keyword(b"in")?;
             let poly_args = self.consume_polymorphic_args(h, allow_inference)?;
             let poly_arg = reduce_port_poly_args(h, &pos, poly_args)
                 .map_err(|infer_error|  {
                     let msg = if infer_error {
                         "Type inference is not allowed here"
                     } else {
                         "Type 'in' only allows for 1 polymorphic argument"
                     };
                     ParseError2::new_error(&self.source, pos, msg)
                 })?;
             ParserTypeVariant::Input(poly_arg)
         } else if self.has_keyword(b"out") {
             // TODO: @hack, temporarily allow inferred port values
             self.consume_keyword(b"out")?;
             let poly_args = self.consume_polymorphic_args(h, allow_inference)?;
             let poly_arg = reduce_port_poly_args(h, &pos, poly_args)
                 .map_err(|infer_error| {
                     let msg = if infer_error {
                         "Type inference is not allowed here"
                     } else {
                         "Type 'out' only allows for 1 polymorphic argument, but {} were specified"
                     };
                     ParseError2::new_error(&self.source, pos, msg)
                 })?;
             ParserTypeVariant::Output(poly_arg)
         } else {
             // Must be a symbolic type
             let identifier = self.consume_namespaced_identifier()?;
             let poly_args = self.consume_polymorphic_args(h, allow_inference)?;
             ParserTypeVariant::Symbolic(SymbolicParserType{identifier, poly_args, variant: None})
         };
         // If the type was a basic type (not supporting polymorphic type
         // arguments), then we make sure the user did not specify any of them.
         let mut backup_pos = self.source.pos();
         if !parser_type_variant.supports_polymorphic_args() {
             self.consume_whitespace(false)?;
             if let Some(b'<') = self.source.next() {
                 return Err(ParseError2::new_error(
                     &self.source, self.source.pos(),
                     "This type does not allow polymorphic arguments"
                 ));
+            }
             self.source.seek(backup_pos);
+        }
         let mut parser_type_id = h.alloc_parser_type(|this| ParserType{
             this, pos, variant: parser_type_variant
         });
         // If we're dealing with arrays, then we need to wrap the currently
         // parsed type in array types
         self.consume_whitespace(false)?;
         while let Some(b'[') = self.source.next() {
             let pos = self.source.pos();
             self.source.consume();
             self.consume_whitespace(false)?;
             if let Some(b']') = self.source.next() {
                 // Type is wrapped in an array
                 self.source.consume();
                 parser_type_id = h.alloc_parser_type(|this| ParserType{
                     this, pos, variant: ParserTypeVariant::Array(parser_type_id)
                 });
                 backup_pos = self.source.pos();
                 // In case we're dealing with another array
                 self.consume_whitespace(false)?;
             } else {
                 return Err(ParseError2::new_error(
                     &self.source, pos,
                     "Expected a closing ']'"
                 ));
+            }
+        }
         self.source.seek(backup_pos);
         Ok(parser_type_id)
+    }
     /// Consumes things that look like types. If everything seems to look like
     /// a type then `true` will be returned and the input position will be
     /// placed after the type. If it doesn't appear to be a type then `false`
     /// will be returned.
     /// TODO: @cleanup, this is not particularly pretty or robust, methinks
     fn maybe_consume_type_spilled(&mut self) -> bool {
         // Spilling polymorphic args. Don't care about the input position
         fn maybe_consume_polymorphic_args(v: &mut Lexer) -> bool {
             if v.consume_whitespace(false).is_err() { return false; }
             if let Some(b'<') = v.source.next() {
                 v.source.consume();
                 if v.consume_whitespace(false).is_err() { return false; }
                 loop {
                     if !maybe_consume_type_inner(v) { return false; }
                     if v.consume_whitespace(false).is_err() { return false; }
                     let has_comma = v.source.next() == Some(b',');
                     if has_comma {
                         v.source.consume();
                         if v.consume_whitespace(false).is_err() { return false; }
+                    }
                     if let Some(b'>') = v.source.next() {
                         v.source.consume();
                         break;
                     } else if !has_comma {
                         return false;
+                    }
+                }
+            }
             return true;
+        }
         // Inner recursive type parser. This method simply advances the lexer
         // and does not store the backup position in case parsing fails
         fn maybe_consume_type_inner(v: &mut Lexer) -> bool {
             // Consume type identifier and optional polymorphic args
             if v.has_type_keyword() {
                 v.consume_any_chars()
     /// Attempts to consume a type without returning it. If it doesn't encounter
     /// a well-formed type, then the input position is left at a "random"
     /// position.
     fn maybe_consume_type_spilled_without_pos_recovery(&mut self) -> bool {
         // Consume type identifier
         if self.has_type_keyword() {
             self.consume_any_chars();
         } else {
                 let ident = v.consume_namespaced_identifier();
                 if ident.is_err() { return false }
             let ident = self.consume_namespaced_identifier();
             if ident.is_err() { return false; }
+        }
             if !maybe_consume_polymorphic_args(v) { return false; }
         // Consume any polymorphic arguments that follow the type identifier
         if self.consume_whitespace(false).is_err() { return false; }
         if !self.maybe_consume_poly_args_spilled_without_pos_recovery() { return false; }
             // Check if wrapped in array
             if v.consume_whitespace(false).is_err() { return false }
             while let Some(b'[') = v.source.next() {
                 v.source.consume();
                 if v.consume_whitespace(false).is_err() { return false; }
                 if Some(b']') != v.source.next() { return false; }
                 v.source.consume();
         // Consume any array specifiers. Make sure we always leave the input
         // position at the end of the last array specifier if we do find a
         // valid type
         let mut backup_pos = self.source.pos();
         if self.consume_whitespace(false).is_err() { return false; }
         while let Some(b'[') = self.source.next() {
             self.source.consume();
             if self.consume_whitespace(false).is_err() { return false; }
             if self.source.next() != Some(b']') { return false; }
             self.source.consume();
             backup_pos = self.source.pos();
             if self.consume_whitespace(false).is_err() { return false; }
+        }
         self.source.seek(backup_pos);
         return true;
+    }
     fn maybe_consume_type_spilled(&mut self) -> bool {
         let backup_pos = self.source.pos();
         if !maybe_consume_type_inner(self) {
             // Not a type
         if !self.maybe_consume_type_spilled_without_pos_recovery() {
             self.source.seek(backup_pos);
             return false;
+        }
         return true;
+    }
     /// Attempts to consume polymorphic arguments without returning them. If it
     /// doesn't encounter well-formed polymorphic arguments, then the input
     /// position is left at a "random" position.
     fn maybe_consume_poly_args_spilled_without_pos_recovery(&mut self) -> bool {
         if let Some(b'<') = self.source.next() {
             self.source.consume();
             if self.consume_whitespace(false).is_err() { return false; }
             loop {
                 if !self.maybe_consume_type_spilled_without_pos_recovery() { return false; }
                 if self.consume_whitespace(false).is_err() { return false; }
                 let has_comma = self.source.next() == Some(b',');
                 if has_comma {
                     self.source.consume();
                     if self.consume_whitespace(false).is_err() { return false; }
+                }
                 if let Some(b'>') = self.source.next() {
                     self.source.consume();
                     break;
                 } else if !has_comma {
                     return false;
+                }
+            }
+        }
         return true;
+    }
     /// Consumes polymorphic arguments and its delimiters if specified. The
     /// input position may be at whitespace. If polyargs are present then the
     /// whitespace and the args are consumed and the input position will be
     /// placed after the polyarg list. If polyargs are not present then the
     /// input position will remain unmodified and an empty vector will be
     /// returned.
     ///
     /// Polymorphic arguments represent the specification of the parametric
     /// types of a polymorphic type: they specify the value of the polymorphic
     /// type's polymorphic variables.
     fn consume_polymorphic_args(&mut self, h: &mut Heap, allow_inference: bool) -> Result<Vec<ParserTypeId>, ParseError2> {
         let backup_pos = self.source.pos();
         self.consume_whitespace(false)?;
         if let Some(b'<') = self.source.next() {
             // Has polymorphic args, at least one type must be specified
             self.source.consume();
             self.consume_whitespace(false)?;
             let mut poly_args = Vec::new();
             loop {
                 // TODO: @cleanup, remove the no_more_types var
                 poly_args.push(self.consume_type2(h, allow_inference)?);
                 self.consume_whitespace(false)?;
                 let has_comma = self.source.next() == Some(b',');
                 if has_comma {
                     // We might not actually be getting more types when the
                     // comma is at the end of the line, and we get a closing
                     // angular bracket on the next line.
                     self.source.consume();
                     self.consume_whitespace(false)?;
+                }
                 if let Some(b'>') = self.source.next() {
                     self.source.consume();
                     break;
                 } else if !has_comma {
                     return Err(ParseError2::new_error(
                         &self.source, self.source.pos(),
                         "Expected the end of the polymorphic argument list"
                     ))
+                }
+            }
             Ok(poly_args)
         } else {
             // No polymorphic args
             self.source.seek(backup_pos);
             Ok(vec!())
+        }
+    }
     /// Consumes polymorphic variables. These are identifiers that are used
     /// within polymorphic types. The input position may be at whitespace. If
     /// polymorphic variables are present then the whitespace, wrapping
     /// delimiters and the polymorphic variables are consumed. Otherwise the
     /// input position will stay where it is. If no polymorphic variables are
     /// present then an empty vector will be returned.
     fn consume_polymorphic_vars(&mut self) -> Result<Vec<Identifier>, ParseError2> {
         let backup_pos = self.source.pos();
         self.consume_whitespace(false)?;
         if let Some(b'<') = self.source.next() {
             // Found the opening delimiter, we want at least one polyvar
             self.source.consume();
             self.consume_whitespace(false)?;
             let mut poly_vars = Vec::new();
             loop {
                 poly_vars.push(self.consume_identifier()?);
                 self.consume_whitespace(false)?;
                 let has_comma = self.source.next() == Some(b',');
                 if has_comma {
                     // We may get another variable
                     self.source.consume();
                     self.consume_whitespace(false)?;
+                }
                 if let Some(b'>') = self.source.next() {
                     self.source.consume();
                     break;
                 } else if !has_comma {
                     return Err(ParseError2::new_error(
                         &self.source, self.source.pos(),
                         "Expected the end of the polymorphic variable list"
                     ))
+                }
+            }
             Ok(poly_vars)
         } else {
             // No polymorphic args
             self.source.seek(backup_pos);
             Ok(vec!())
+        }
+    }
     // Parameters
     fn consume_parameter(&mut self, h: &mut Heap) -> Result<ParameterId, ParseError2> {
         let parser_type = self.consume_type2(h, false)?;
         self.consume_whitespace(true)?;
         let position = self.source.pos();
         let identifier = self.consume_identifier()?;
         let id =
             h.alloc_parameter(|this| Parameter { this, position, parser_type, identifier });
         Ok(id)
+    }
     fn consume_parameters(
         &mut self,
         h: &mut Heap,
         params: &mut Vec<ParameterId>,
     ) -> Result<(), ParseError2> {
         self.consume_string(b"(")?;
         self.consume_whitespace(false)?;
         if !self.has_string(b")") {
             while self.source.next().is_some() {
                 params.push(self.consume_parameter(h)?);
                 self.consume_whitespace(false)?;
                 if self.has_string(b")") {
                     break;
+                }
                 self.consume_string(b",")?;
                 self.consume_whitespace(false)?;
+            }
+        }
         self.consume_string(b")")?;
         Ok(())
+    }
     // ====================
     // Expressions
     // ====================
     fn consume_paren_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         self.consume_string(b"(")?;
         self.consume_whitespace(false)?;
         let result = self.consume_expression(h)?;
         self.consume_whitespace(false)?;
         self.consume_string(b")")?;
         Ok(result)
+    }
     fn consume_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         if self.level >= MAX_LEVEL {
             return Err(self.error_at_pos("Too deeply nested expression"));
+        }
         self.level += 1;
         let result = self.consume_assignment_expression(h);
         self.level -= 1;
         result
+    }
     fn consume_assignment_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let result = self.consume_conditional_expression(h)?;
         self.consume_whitespace(false)?;
         if self.has_assignment_operator() {
             let position = self.source.pos();
             let left = result;
             let operation = self.consume_assignment_operator()?;
             self.consume_whitespace(false)?;
             let right = self.consume_expression(h)?;
             Ok(h.alloc_assignment_expression(|this| AssignmentExpression {
                 this,
                 position,
                 left,
                 operation,
                 right,
                 parent: ExpressionParent::None,
             })
             .upcast())
         } else {
             Ok(result)
+        }
+    }
     fn has_assignment_operator(&self) -> bool {
         self.has_string(b"=")
             || self.has_string(b"*=")
             || self.has_string(b"/=")
             || self.has_string(b"%=")
             || self.has_string(b"+=")
             || self.has_string(b"-=")
             || self.has_string(b"<<=")
             || self.has_string(b">>=")
             || self.has_string(b"&=")
             || self.has_string(b"^=")
             || self.has_string(b"|=")
+    }
     fn consume_assignment_operator(&mut self) -> Result<AssignmentOperator, ParseError2> {
         if self.has_string(b"=") {
             self.consume_string(b"=")?;
             Ok(AssignmentOperator::Set)
         } else if self.has_string(b"*=") {
             self.consume_string(b"*=")?;
             Ok(AssignmentOperator::Multiplied)
         } else if self.has_string(b"/=") {
             self.consume_string(b"/=")?;
             Ok(AssignmentOperator::Divided)
         } else if self.has_string(b"%=") {
             self.consume_string(b"%=")?;
             Ok(AssignmentOperator::Remained)
         } else if self.has_string(b"+=") {
             self.consume_string(b"+=")?;
             Ok(AssignmentOperator::Added)
         } else if self.has_string(b"-=") {
             self.consume_string(b"-=")?;
             Ok(AssignmentOperator::Subtracted)
         } else if self.has_string(b"<<=") {
             self.consume_string(b"<<=")?;
             Ok(AssignmentOperator::ShiftedLeft)
         } else if self.has_string(b">>=") {
             self.consume_string(b">>=")?;
             Ok(AssignmentOperator::ShiftedRight)
         } else if self.has_string(b"&=") {
             self.consume_string(b"&=")?;
             Ok(AssignmentOperator::BitwiseAnded)
         } else if self.has_string(b"^=") {
             self.consume_string(b"^=")?;
             Ok(AssignmentOperator::BitwiseXored)
         } else if self.has_string(b"|=") {
             self.consume_string(b"|=")?;
             Ok(AssignmentOperator::BitwiseOred)
         } else {
             Err(self.error_at_pos("Expected assignment operator"))
+        }
+    }
     fn consume_conditional_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let result = self.consume_concat_expression(h)?;
         self.consume_whitespace(false)?;
         if self.has_string(b"?") {
             let position = self.source.pos();
             let test = result;
             self.consume_string(b"?")?;
             self.consume_whitespace(false)?;
             let true_expression = self.consume_expression(h)?;
             self.consume_whitespace(false)?;
             self.consume_string(b":")?;
             self.consume_whitespace(false)?;
             let false_expression = self.consume_expression(h)?;
             Ok(h.alloc_conditional_expression(|this| ConditionalExpression {
                 this,
                 position,
                 test,
                 true_expression,
                 false_expression,
                 parent: ExpressionParent::None,
             })
             .upcast())
         } else {
             Ok(result)
+        }
+    }
     fn consume_concat_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let mut result = self.consume_lor_expression(h)?;
         self.consume_whitespace(false)?;
         while self.has_string(b"@") {
             let position = self.source.pos();
             let left = result;
             self.consume_string(b"@")?;
             let operation = BinaryOperator::Concatenate;
             self.consume_whitespace(false)?;
             let right = self.consume_lor_expression(h)?;
             self.consume_whitespace(false)?;
             result = h
                 .alloc_binary_expression(|this| BinaryExpression {
                     this,
                     position,
                     left,
                     operation,
                     right,
                     parent: ExpressionParent::None,
                 })
                 .upcast();
+        }
         Ok(result)
+    }
     fn consume_lor_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let mut result = self.consume_land_expression(h)?;
         self.consume_whitespace(false)?;
         while self.has_string(b"||") {
             let position = self.source.pos();
             let left = result;
             self.consume_string(b"||")?;
             let operation = BinaryOperator::LogicalOr;
             self.consume_whitespace(false)?;
             let right = self.consume_land_expression(h)?;
             self.consume_whitespace(false)?;
             result = h
                 .alloc_binary_expression(|this| BinaryExpression {
                     this,
                     position,
                     left,
                     operation,
                     right,
                     parent: ExpressionParent::None,
                 })
                 .upcast();
+        }
         Ok(result)
+    }
     fn consume_land_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let mut result = self.consume_bor_expression(h)?;
         self.consume_whitespace(false)?;
         while self.has_string(b"&&") {
             let position = self.source.pos();
             let left = result;
             self.consume_string(b"&&")?;
             let operation = BinaryOperator::LogicalAnd;
             self.consume_whitespace(false)?;
             let right = self.consume_bor_expression(h)?;
             self.consume_whitespace(false)?;
             result = h
                 .alloc_binary_expression(|this| BinaryExpression {
                     this,
                     position,
                     left,
                     operation,
                     right,
                     parent: ExpressionParent::None,
                 })
                 .upcast();
+        }
         Ok(result)
+    }
     fn consume_bor_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let mut result = self.consume_xor_expression(h)?;
         self.consume_whitespace(false)?;
         while self.has_string(b"|") && !self.has_string(b"||") && !self.has_string(b"|=") {
             let position = self.source.pos();
             let left = result;
             self.consume_string(b"|")?;
             let operation = BinaryOperator::BitwiseOr;
             self.consume_whitespace(false)?;
             let right = self.consume_xor_expression(h)?;
             self.consume_whitespace(false)?;
             result = h
                 .alloc_binary_expression(|this| BinaryExpression {
                     this,
                     position,
                     left,
                     operation,
                     right,
                     parent: ExpressionParent::None,
                 })
                 .upcast();
+        }
         Ok(result)
+    }
     fn consume_xor_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let mut result = self.consume_band_expression(h)?;
         self.consume_whitespace(false)?;
         while self.has_string(b"^") && !self.has_string(b"^=") {
             let position = self.source.pos();
             let left = result;
             self.consume_string(b"^")?;
             let operation = BinaryOperator::BitwiseXor;
             self.consume_whitespace(false)?;
             let right = self.consume_band_expression(h)?;
             self.consume_whitespace(false)?;
             result = h
                 .alloc_binary_expression(|this| BinaryExpression {
                     this,
                     position,
                     left,
                     operation,
                     right,
                     parent: ExpressionParent::None,
                 })
                 .upcast();
+        }
         Ok(result)
+    }
     fn consume_band_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let mut result = self.consume_eq_expression(h)?;
         self.consume_whitespace(false)?;
         while self.has_string(b"&") && !self.has_string(b"&&") && !self.has_string(b"&=") {
             let position = self.source.pos();
             let left = result;
             self.consume_string(b"&")?;
             let operation = BinaryOperator::BitwiseAnd;
             self.consume_whitespace(false)?;
             let right = self.consume_eq_expression(h)?;
             self.consume_whitespace(false)?;
             result = h
                 .alloc_binary_expression(|this| BinaryExpression {
                     this,
                     position,
                     left,
                     operation,
                     right,
                     parent: ExpressionParent::None,
                 })
                 .upcast();
+        }
         Ok(result)
+    }
     fn consume_eq_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let mut result = self.consume_rel_expression(h)?;
         self.consume_whitespace(false)?;
         while self.has_string(b"==") || self.has_string(b"!=") {
             let position = self.source.pos();
             let left = result;
             let operation;
             if self.has_string(b"==") {
                 self.consume_string(b"==")?;
                 operation = BinaryOperator::Equality;
             } else {
                 self.consume_string(b"!=")?;
                 operation = BinaryOperator::Inequality;
+            }
             self.consume_whitespace(false)?;
             let right = self.consume_rel_expression(h)?;
             self.consume_whitespace(false)?;
             result = h
                 .alloc_binary_expression(|this| BinaryExpression {
                     this,
                     position,
                     left,
                     operation,
                     right,
                     parent: ExpressionParent::None,
                 })
                 .upcast();
+        }
         Ok(result)
+    }
     fn consume_rel_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let mut result = self.consume_shift_expression(h)?;
         self.consume_whitespace(false)?;
         while self.has_string(b"<=")
             || self.has_string(b">=")
             || self.has_string(b"<") && !self.has_string(b"<<=")
             || self.has_string(b">") && !self.has_string(b">>=")
+        {
             let position = self.source.pos();
             let left = result;
             let operation;
             if self.has_string(b"<=") {
                 self.consume_string(b"<=")?;
                 operation = BinaryOperator::LessThanEqual;
             } else if self.has_string(b">=") {
                 self.consume_string(b">=")?;
                 operation = BinaryOperator::GreaterThanEqual;
             } else if self.has_string(b"<") {
                 self.consume_string(b"<")?;
                 operation = BinaryOperator::LessThan;
             } else {
                 self.consume_string(b">")?;
                 operation = BinaryOperator::GreaterThan;
+            }
             self.consume_whitespace(false)?;
             let right = self.consume_shift_expression(h)?;
             self.consume_whitespace(false)?;
             result = h
                 .alloc_binary_expression(|this| BinaryExpression {
                     this,
                     position,
                     left,
                     operation,
                     right,
                     parent: ExpressionParent::None,
                 })
                 .upcast();
+        }
         Ok(result)
+    }
     fn consume_shift_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let mut result = self.consume_add_expression(h)?;
         self.consume_whitespace(false)?;
         while self.has_string(b"<<") && !self.has_string(b"<<=")
             || self.has_string(b">>") && !self.has_string(b">>=")
+        {
             let position = self.source.pos();
             let left = result;
             let operation;
             if self.has_string(b"<<") {
                 self.consume_string(b"<<")?;
                 operation = BinaryOperator::ShiftLeft;
             } else {
                 self.consume_string(b">>")?;
                 operation = BinaryOperator::ShiftRight;
+            }
             self.consume_whitespace(false)?;
             let right = self.consume_add_expression(h)?;
             self.consume_whitespace(false)?;
             result = h
                 .alloc_binary_expression(|this| BinaryExpression {
                     this,
                     position,
                     left,
                     operation,
                     right,
                     parent: ExpressionParent::None,
                 })
                 .upcast();
+        }
         Ok(result)
+    }
     fn consume_add_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let mut result = self.consume_mul_expression(h)?;
         self.consume_whitespace(false)?;
         while self.has_string(b"+") && !self.has_string(b"+=")
             || self.has_string(b"-") && !self.has_string(b"-=")
+        {
             let position = self.source.pos();
             let left = result;
             let operation;
             if self.has_string(b"+") {
                 self.consume_string(b"+")?;
                 operation = BinaryOperator::Add;
             } else {
                 self.consume_string(b"-")?;
                 operation = BinaryOperator::Subtract;
+            }
             self.consume_whitespace(false)?;
             let right = self.consume_mul_expression(h)?;
             self.consume_whitespace(false)?;
             result = h
                 .alloc_binary_expression(|this| BinaryExpression {
                     this,
                     position,
                     left,
                     operation,
                     right,
                     parent: ExpressionParent::None,
                 })
                 .upcast();
+        }
         Ok(result)
+    }
     fn consume_mul_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let mut result = self.consume_prefix_expression(h)?;
         self.consume_whitespace(false)?;
         while self.has_string(b"*") && !self.has_string(b"*=")
             || self.has_string(b"/") && !self.has_string(b"/=")
             || self.has_string(b"%") && !self.has_string(b"%=")
+        {
             let position = self.source.pos();
             let left = result;
             let operation;
             if self.has_string(b"*") {
                 self.consume_string(b"*")?;
                 operation = BinaryOperator::Multiply;
             } else if self.has_string(b"/") {
                 self.consume_string(b"/")?;
                 operation = BinaryOperator::Divide;
             } else {
                 self.consume_string(b"%")?;
                 operation = BinaryOperator::Remainder;
+            }
             self.consume_whitespace(false)?;
             let right = self.consume_prefix_expression(h)?;
             self.consume_whitespace(false)?;
             result = h
                 .alloc_binary_expression(|this| BinaryExpression {
                     this,
                     position,
                     left,
                     operation,
                     right,
                     parent: ExpressionParent::None,
                 })
                 .upcast();
+        }
         Ok(result)
+    }
     fn consume_prefix_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         if self.has_string(b"+")
             || self.has_string(b"-")
             || self.has_string(b"~")
             || self.has_string(b"!")
+        {
             let position = self.source.pos();
             let operation;
             if self.has_string(b"+") {
                 self.consume_string(b"+")?;
                 if self.has_string(b"+") {
                     self.consume_string(b"+")?;
                     operation = UnaryOperation::PreIncrement;
                 } else {
                     operation = UnaryOperation::Positive;
+                }
             } else if self.has_string(b"-") {
                 self.consume_string(b"-")?;
                 if self.has_string(b"-") {
                     self.consume_string(b"-")?;
                     operation = UnaryOperation::PreDecrement;
                 } else {
                     operation = UnaryOperation::Negative;
+                }
             } else if self.has_string(b"~") {
                 self.consume_string(b"~")?;
                 operation = UnaryOperation::BitwiseNot;
             } else {
                 self.consume_string(b"!")?;
                 operation = UnaryOperation::LogicalNot;
+            }
             self.consume_whitespace(false)?;
             if self.level >= MAX_LEVEL {
                 return Err(self.error_at_pos("Too deeply nested expression"));
+            }
             self.level += 1;
             let result = self.consume_prefix_expression(h);
             self.level -= 1;
             let expression = result?;
             return Ok(h
                 .alloc_unary_expression(|this| UnaryExpression {
                     this,
                     position,
                     operation,
                     expression,
                     parent: ExpressionParent::None,
                 })
                 .upcast());
+        }
         self.consume_postfix_expression(h)
+    }
     fn consume_postfix_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         let mut result = self.consume_primary_expression(h)?;
         self.consume_whitespace(false)?;
         while self.has_string(b"++")
             || self.has_string(b"--")
             || self.has_string(b"[")
             || (self.has_string(b".") && !self.has_string(b".."))
+        {
             let mut position = self.source.pos();
             if self.has_string(b"++") {
                 self.consume_string(b"++")?;
                 let operation = UnaryOperation::PostIncrement;
                 let expression = result;
                 self.consume_whitespace(false)?;
                 result = h
                     .alloc_unary_expression(|this| UnaryExpression {
                         this,
                         position,
                         operation,
                         expression,
                         parent: ExpressionParent::None,
                     })
                     .upcast();
             } else if self.has_string(b"--") {
                 self.consume_string(b"--")?;
                 let operation = UnaryOperation::PostDecrement;
                 let expression = result;
                 self.consume_whitespace(false)?;
                 result = h
                     .alloc_unary_expression(|this| UnaryExpression {
                         this,
                         position,
                         operation,
                         expression,
                         parent: ExpressionParent::None,
                     })
                     .upcast();
             } else if self.has_string(b"[") {
                 self.consume_string(b"[")?;
                 self.consume_whitespace(false)?;
                 let subject = result;
                 let index = self.consume_expression(h)?;
                 self.consume_whitespace(false)?;
                 if self.has_string(b"..") || self.has_string(b":") {
                     position = self.source.pos();
                     if self.has_string(b"..") {
                         self.consume_string(b"..")?;
                     } else {
                         self.consume_string(b":")?;
+                    }
                     self.consume_whitespace(false)?;
                     let to_index = self.consume_expression(h)?;
                     self.consume_whitespace(false)?;
                     result = h
                         .alloc_slicing_expression(|this| SlicingExpression {
                             this,
                             position,
                             subject,
                             from_index: index,
                             to_index,
                             parent: ExpressionParent::None,
                         })
                         .upcast();
                 } else {
                     result = h
                         .alloc_indexing_expression(|this| IndexingExpression {
                             this,
                             position,
                             subject,
                             index,
                             parent: ExpressionParent::None,
                         })
                         .upcast();
+                }
                 self.consume_string(b"]")?;
                 self.consume_whitespace(false)?;
             } else {
                 assert!(self.has_string(b"."));
                 self.consume_string(b".")?;
                 self.consume_whitespace(false)?;
                 let subject = result;
                 let field;
                 if self.has_keyword(b"length") {
                     self.consume_keyword(b"length")?;
                     field = Field::Length;
                 } else {
                     field = Field::Symbolic(self.consume_identifier()?);
+                }
                 result = h
                     .alloc_select_expression(|this| SelectExpression {
                         this,
                         position,
                         subject,
                         field,
                         parent: ExpressionParent::None,
                     })
                     .upcast();
+            }
+        }
         Ok(result)
+    }
     fn consume_primary_expression(&mut self, h: &mut Heap) -> Result<ExpressionId, ParseError2> {
         if self.has_string(b"(") {
             return self.consume_paren_expression(h);
+        }
         if self.has_string(b"{") {
             return Ok(self.consume_array_expression(h)?.upcast());
+        }
         if self.has_constant()
             || self.has_keyword(b"null")
             || self.has_keyword(b"true")
             || self.has_keyword(b"false")
+        {
             return Ok(self.consume_constant_expression(h)?.upcast());
+        }
         if self.has_call_expression() {
             return Ok(self.consume_call_expression(h)?.upcast());
+        }
         Ok(self.consume_variable_expression(h)?.upcast())
+    }
     fn consume_array_expression(&mut self, h: &mut Heap) -> Result<ArrayExpressionId, ParseError2> {
         let position = self.source.pos();
         let mut elements = Vec::new();
         self.consume_string(b"{")?;
         self.consume_whitespace(false)?;
         if !self.has_string(b"}") {
             while self.source.next().is_some() {
                 elements.push(self.consume_expression(h)?);
                 self.consume_whitespace(false)?;
                 if self.has_string(b"}") {
                     break;
+                }
                 self.consume_string(b",")?;
                 self.consume_whitespace(false)?;
+            }
+        }
         self.consume_string(b"}")?;
         Ok(h.alloc_array_expression(|this| ArrayExpression {
             this,
             position,
             elements,
             parent: ExpressionParent::None,
         }))
+    }
     fn has_constant(&self) -> bool {
         is_constant(self.source.next())
+    }
     fn consume_constant_expression(
         &mut self,
         h: &mut Heap,
     ) -> Result<ConstantExpressionId, ParseError2> {
         let position = self.source.pos();
         let value;
         if self.has_keyword(b"null") {
             self.consume_keyword(b"null")?;
             value = Constant::Null;
         } else if self.has_keyword(b"true") {
             self.consume_keyword(b"true")?;
             value = Constant::True;
         } else if self.has_keyword(b"false") {
             self.consume_keyword(b"false")?;
             value = Constant::False;
         } else if self.source.next() == Some(b'\'') {
             self.source.consume();
             let mut data = Vec::new();
             let mut next = self.source.next();
             while next != Some(b'\'') && (is_vchar(next) || next == Some(b' ')) {
                 data.push(next.unwrap());
                 self.source.consume();
                 next = self.source.next();
+            }
             if next != Some(b'\'') || data.is_empty() {
                 return Err(self.error_at_pos("Expected character constant"));
+            }
             self.source.consume();
             value = Constant::Character(data);
         } else {
             if !self.has_integer() {
                 return Err(self.error_at_pos("Expected integer constant"));
+            }
             value = Constant::Integer(self.consume_integer()?);
+        }
         Ok(h.alloc_constant_expression(|this| ConstantExpression {
             this,
             position,
             value,
             parent: ExpressionParent::None,
         }))
+    }
     fn has_call_expression(&mut self) -> bool {
         /* We prevent ambiguity with variables, by looking ahead
         the identifier to see if we can find an opening
         parenthesis: this signals a call expression. */
         // We need to prevent ambiguity with various operators (because we may
         // be specifying polymorphic variables) and variables.
         if self.has_builtin_keyword() {
             return true;
+        }
         let backup_pos = self.source.pos();
         let mut result = false;
         match self.consume_identifier_spilled() {
             Ok(_) => match self.consume_whitespace(false) {
                 Ok(_) => {
                     result = self.has_string(b"(");
+                }
                 Err(_) => {}
             },
             Err(_) => {}
         if self.consume_namespaced_identifier_spilled().is_ok() &&
             self.consume_whitespace(false).is_ok() &&
             self.maybe_consume_poly_args_spilled_without_pos_recovery().is_ok() &&
             self.consume_whitespace(false).is_ok() &&
             self.source.next() == Some(b'(') {
             // Seems like we have a function call or an enum literal
             result = true;
+        }
         self.source.seek(backup_pos);
         return result;
+    }
     fn consume_call_expression(&mut self, h: &mut Heap) -> Result<CallExpressionId, ParseError2> {
         let position = self.source.pos();
         // Consume method identifier
         let method;
         if self.has_keyword(b"get") {
             self.consume_keyword(b"get")?;
             method = Method::Get;
         } else if self.has_keyword(b"fires") {
             self.consume_keyword(b"fires")?;
             method = Method::Fires;
         } else if self.has_keyword(b"create") {
             self.consume_keyword(b"create")?;
             method = Method::Create;
         } else {
             let identifier = self.consume_namespaced_identifier()?;
             method = Method::Symbolic(MethodSymbolic{
                 identifier,
                 definition: None
             })
+        }
         // Consume polymorphic arguments
         self.consume_whitespace(false)?;
         let poly_args = self.consume_polymorphic_args(h, true)?;
         // Consume arguments to call
         self.consume_whitespace(false)?;
         let mut arguments = Vec::new();
         self.consume_string(b"(")?;
         self.consume_whitespace(false)?;
         if !self.has_string(b")") {
             // TODO: allow trailing comma
             while self.source.next().is_some() {
                 arguments.push(self.consume_expression(h)?);
                 self.consume_whitespace(false)?;
                 if self.has_string(b")") {
                     break;
+                }
                 self.consume_string(b",")?;
                 self.consume_whitespace(false)?
+            }
+        }
         self.consume_string(b")")?;
         Ok(h.alloc_call_expression(|this| CallExpression {
             this,
             position,
             method,
             arguments,
             poly_args,
             parent: ExpressionParent::None,
         }))
+    }
     fn consume_variable_expression(
         &mut self,
         h: &mut Heap,
     ) -> Result<VariableExpressionId, ParseError2> {
         let position = self.source.pos();
         let identifier = self.consume_namespaced_identifier()?;
         Ok(h.alloc_variable_expression(|this| VariableExpression {
             this,
             position,
             identifier,
             declaration: None,
             parent: ExpressionParent::None,
         }))
+    }
     // ====================
     // Statements
     // ====================
     /// Consumes any kind of statement from the source and will error if it
     /// did not encounter a statement. Will also return an error if the
     /// statement is nested too deeply.
     ///
     /// `wrap_in_block` may be set to true to ensure that the parsed statement
     /// will be wrapped in a block statement if it is not already a block
     /// statement. This is used to ensure that all `if`, `while` and `sync`
     /// statements have a block statement as body.
     fn consume_statement(&mut self, h: &mut Heap, wrap_in_block: bool) -> Result<StatementId, ParseError2> {
         if self.level >= MAX_LEVEL {
             return Err(self.error_at_pos("Too deeply nested statement"));
+        }
         self.level += 1;
         let result = self.consume_statement_impl(h, wrap_in_block);
         self.level -= 1;
         result
+    }
     fn has_label(&mut self) -> bool {
         // To prevent ambiguity with expression statements consisting only of an
         // identifier or a namespaced identifier, we look ahead and match on the
         // *single* colon that signals a labeled statement.
         let backup_pos = self.source.pos();
         let mut result = false;
         if self.consume_identifier_spilled().is_ok() {
             // next character is ':', second character is NOT ':'
             result = Some(b':') == self.source.next() && Some(b':') != self.source.lookahead(1)
+        }
         self.source.seek(backup_pos);
         return result;
+    }
     fn consume_statement_impl(&mut self, h: &mut Heap, wrap_in_block: bool) -> Result<StatementId, ParseError2> {
         // Parse and allocate statement
         let mut must_wrap = true;
         let mut stmt_id = if self.has_string(b"{") {
             must_wrap = false;
             self.consume_block_statement(h)?
         } else if self.has_keyword(b"skip") {
             must_wrap = false;
             self.consume_skip_statement(h)?.upcast()
         } else if self.has_keyword(b"if") {
             self.consume_if_statement(h)?.upcast()
         } else if self.has_keyword(b"while") {
             self.consume_while_statement(h)?.upcast()
         } else if self.has_keyword(b"break") {
             self.consume_break_statement(h)?.upcast()
         } else if self.has_keyword(b"continue") {
             self.consume_continue_statement(h)?.upcast()
         } else if self.has_keyword(b"synchronous") {
             self.consume_synchronous_statement(h)?.upcast()
         } else if self.has_keyword(b"return") {
             self.consume_return_statement(h)?.upcast()
         } else if self.has_keyword(b"assert") {
             self.consume_assert_statement(h)?.upcast()
         } else if self.has_keyword(b"goto") {
             self.consume_goto_statement(h)?.upcast()
         } else if self.has_keyword(b"new") {
             self.consume_new_statement(h)?.upcast()
         } else if self.has_keyword(b"put") {
             self.consume_put_statement(h)?.upcast()
         } else if self.has_label() {
             self.consume_labeled_statement(h)?.upcast()
         } else {
             self.consume_expression_statement(h)?.upcast()
         };
         // Wrap if desired and if needed
         if must_wrap && wrap_in_block {
             let position = h[stmt_id].position();
             let block_wrapper = h.alloc_block_statement(|this| BlockStatement{
                 this,
                 position,
                 statements: vec![stmt_id],
                 parent_scope: None,
                 relative_pos_in_parent: 0,
                 locals: Vec::new(),
                 labels: Vec::new()
             });
             stmt_id = block_wrapper.upcast();
+        }
         Ok(stmt_id)
+    }
     fn has_local_statement(&mut self) -> bool {
         /* To avoid ambiguity, we look ahead to find either the
         channel keyword that signals a variable declaration, or
         a type annotation followed by another identifier.
         Example:
           my_type[] x = {5}; // memory statement
           my_var[5] = x; // assignment expression, expression statement
         Note how both the local and the assignment
         start with arbitrary identifier followed by [. */
         if self.has_keyword(b"channel") {
             return true;
+        }
         if self.has_statement_keyword() {
             return false;
+        }
         let backup_pos = self.source.pos();
         let mut result = false;
-        if self.maybe_consume_type_spilled() {
+        if self.maybe_consume_type_spilled_without_pos_recovery() {
             // We seem to have a valid type, do we now have an identifier?
-            if self.consume_whitespace(false).is_ok() {
+            if self.consume_whitespace(true).is_ok() {
                 result = self.has_identifier();
+            }
+        }
         self.source.seek(backup_pos);
         return result;
+    }
     fn consume_block_statement(&mut self, h: &mut Heap) -> Result<StatementId, ParseError2> {
         let position = self.source.pos();
         let mut statements = Vec::new();
         self.consume_string(b"{")?;
         self.consume_whitespace(false)?;
         while self.has_local_statement() {
             statements.push(self.consume_local_statement(h)?.upcast());
             self.consume_whitespace(false)?;
+        }
         while !self.has_string(b"}") {
             statements.push(self.consume_statement(h, false)?);
             self.consume_whitespace(false)?;
+        }
         self.consume_string(b"}")?;
         if statements.is_empty() {
             Ok(h.alloc_skip_statement(|this| SkipStatement { this, position, next: None }).upcast())
         } else {
             Ok(h.alloc_block_statement(|this| BlockStatement {
                 this,
                 position,
                 statements,
                 parent_scope: None,
                 relative_pos_in_parent: 0,
                 locals: Vec::new(),
                 labels: Vec::new(),
             })
             .upcast())
+        }
+    }
     fn consume_local_statement(&mut self, h: &mut Heap) -> Result<LocalStatementId, ParseError2> {
         if self.has_keyword(b"channel") {
             Ok(self.consume_channel_statement(h)?.upcast())
         } else {
             Ok(self.consume_memory_statement(h)?.upcast())
+        }
+    }
     fn consume_channel_statement(
         &mut self,
         h: &mut Heap,
     ) -> Result<ChannelStatementId, ParseError2> {
         // Consume channel statement and polymorphic argument if specified
         let position = self.source.pos();
         self.consume_keyword(b"channel")?;
         let poly_args = self.consume_polymorphic_args(h, true)?;
         let poly_arg_id = match poly_args.len() {
 => h.alloc_parser_type(|this| ParserType{
                 this, pos: position.clone(), variant: ParserTypeVariant::Inferred,
             }),
 => poly_args[0],
             _ => return Err(ParseError2::new_error(
                 &self.source, self.source.pos(),
                 "port construction using 'channel' accepts up to 1 polymorphic argument"
             ))
         };
         self.consume_whitespace(true)?;
         // Consume the output port
         let out_parser_type = h.alloc_parser_type(|this| ParserType{
             this, pos: position.clone(), variant: ParserTypeVariant::Output(poly_arg_id)
         });
         let out_identifier = self.consume_identifier()?;
         // Consume the "->" syntax
         self.consume_whitespace(false)?;
         self.consume_string(b"->")?;
         self.consume_whitespace(false)?;
         // Consume the input port
         // TODO: Unsure about this, both ports refer to the same ParserType, is this ok?
         let in_parser_type = h.alloc_parser_type(|this| ParserType{
             this, pos: position.clone(), variant: ParserTypeVariant::Input(poly_arg_id)
         });
         let in_identifier = self.consume_identifier()?;
         self.consume_whitespace(false)?;
         self.consume_string(b";")?;
         let out_port = h.alloc_local(|this| Local {
             this,
             position,
             parser_type: out_parser_type,
             identifier: out_identifier,
             relative_pos_in_block: 0
         });
         let in_port = h.alloc_local(|this| Local {
             this,
             position,
             parser_type: in_parser_type,
             identifier: in_identifier,
             relative_pos_in_block: 0
         });
         Ok(h.alloc_channel_statement(|this| ChannelStatement {
             this,
             position,
             from: out_port,
             to: in_port,
             relative_pos_in_block: 0,
             next: None,
         }))
+    }
     fn consume_memory_statement(&mut self, h: &mut Heap) -> Result<MemoryStatementId, ParseError2> {
         let position = self.source.pos();
         let parser_type = self.consume_type2(h, true)?;
         self.consume_whitespace(true)?;
         let identifier = self.consume_identifier()?;
         self.consume_whitespace(false)?;
         self.consume_string(b"=")?;
         self.consume_whitespace(false)?;
         let initial = self.consume_expression(h)?;
         let variable = h.alloc_local(|this| Local {
             this,
             position,
             parser_type,
             identifier,
             relative_pos_in_block: 0
         });
         self.consume_whitespace(false)?;
         self.consume_string(b";")?;
         Ok(h.alloc_memory_statement(|this| MemoryStatement {
             this,
             position,
             variable,
             initial,
             next: None,
         }))
+    }
     fn consume_labeled_statement(
         &mut self,
         h: &mut Heap,
     ) -> Result<LabeledStatementId, ParseError2> {
         let position = self.source.pos();
         let label = self.consume_identifier()?;
         self.consume_whitespace(false)?;
         self.consume_string(b":")?;
         self.consume_whitespace(false)?;
         let body = self.consume_statement(h, false)?;
         Ok(h.alloc_labeled_statement(|this| LabeledStatement {
             this,
             position,
             label,
             body,
             relative_pos_in_block: 0,
             in_sync: None,
         }))
+    }
     fn consume_skip_statement(&mut self, h: &mut Heap) -> Result<SkipStatementId, ParseError2> {
         let position = self.source.pos();
         self.consume_keyword(b"skip")?;
         self.consume_whitespace(false)?;
         self.consume_string(b";")?;
         Ok(h.alloc_skip_statement(|this| SkipStatement { this, position, next: None }))
+    }
     fn consume_if_statement(&mut self, h: &mut Heap) -> Result<IfStatementId, ParseError2> {
         let position = self.source.pos();
         self.consume_keyword(b"if")?;
         self.consume_whitespace(false)?;
         let test = self.consume_paren_expression(h)?;
         self.consume_whitespace(false)?;
         let true_body = self.consume_statement(h, true)?;
         self.consume_whitespace(false)?;
         let false_body = if self.has_keyword(b"else") {
             self.consume_keyword(b"else")?;
             self.consume_whitespace(false)?;
             self.consume_statement(h, true)?
         } else {
             h.alloc_skip_statement(|this| SkipStatement { this, position, next: None }).upcast()
         };
         Ok(h.alloc_if_statement(|this| IfStatement { this, position, test, true_body, false_body, end_if: None }))
+    }
     fn consume_while_statement(&mut self, h: &mut Heap) -> Result<WhileStatementId, ParseError2> {
         let position = self.source.pos();
         self.consume_keyword(b"while")?;
         self.consume_whitespace(false)?;
         let test = self.consume_paren_expression(h)?;
         self.consume_whitespace(false)?;
         let body = self.consume_statement(h, true)?;
         Ok(h.alloc_while_statement(|this| WhileStatement {
             this,
             position,
             test,
             body,
             end_while: None,
             in_sync: None,
         }))
+    }
     fn consume_break_statement(&mut self, h: &mut Heap) -> Result<BreakStatementId, ParseError2> {
         let position = self.source.pos();
         self.consume_keyword(b"break")?;
         self.consume_whitespace(false)?;
         let label;
         if self.has_identifier() {
             label = Some(self.consume_identifier()?);
             self.consume_whitespace(false)?;
         } else {
             label = None;
+        }
         self.consume_string(b";")?;
         Ok(h.alloc_break_statement(|this| BreakStatement { this, position, label, target: None }))
+    }
     fn consume_continue_statement(
         &mut self,
         h: &mut Heap,
     ) -> Result<ContinueStatementId, ParseError2> {
         let position = self.source.pos();
         self.consume_keyword(b"continue")?;
         self.consume_whitespace(false)?;
         let label;
         if self.has_identifier() {
             label = Some(self.consume_identifier()?);
             self.consume_whitespace(false)?;
         } else {
             label = None;
+        }
         self.consume_string(b";")?;
         Ok(h.alloc_continue_statement(|this| ContinueStatement {
             this,
             position,
             label,
             target: None,
         }))
+    }
     fn consume_synchronous_statement(
         &mut self,
         h: &mut Heap,
     ) -> Result<SynchronousStatementId, ParseError2> {
         let position = self.source.pos();
         self.consume_keyword(b"synchronous")?;
         self.consume_whitespace(false)?;
         // TODO: What was the purpose of this? Seems superfluous and confusing?
         // let mut parameters = Vec::new();
         // if self.has_string(b"(") {
         //     self.consume_parameters(h, &mut parameters)?;
         //     self.consume_whitespace(false)?;
         // } else if !self.has_keyword(b"skip") && !self.has_string(b"{") {
         //     return Err(self.error_at_pos("Expected block statement"));
         // }
         let body = self.consume_statement(h, true)?;
         Ok(h.alloc_synchronous_statement(|this| SynchronousStatement {
             this,
             position,
             body,
             end_sync: None,
             parent_scope: None,
         }))
+    }
     fn consume_return_statement(&mut self, h: &mut Heap) -> Result<ReturnStatementId, ParseError2> {
         let position = self.source.pos();
         self.consume_keyword(b"return")?;
         self.consume_whitespace(false)?;
         let expression = if self.has_string(b"(") {
             self.consume_paren_expression(h)
         } else {
             self.consume_expression(h)
         }?;
         self.consume_whitespace(false)?;
         self.consume_string(b";")?;
         Ok(h.alloc_return_statement(|this| ReturnStatement { this, position, expression }))
+    }
     fn consume_assert_statement(&mut self, h: &mut Heap) -> Result<AssertStatementId, ParseError2> {
         let position = self.source.pos();
         self.consume_keyword(b"assert")?;
         self.consume_whitespace(false)?;
         let expression = if self.has_string(b"(") {
             self.consume_paren_expression(h)
         } else {
             self.consume_expression(h)
         }?;
         self.consume_whitespace(false)?;
         self.consume_string(b";")?;
         Ok(h.alloc_assert_statement(|this| AssertStatement {
             this,
             position,
             expression,
             next: None,
         }))
+    }
     fn consume_goto_statement(&mut self, h: &mut Heap) -> Result<GotoStatementId, ParseError2> {
         let position = self.source.pos();
         self.consume_keyword(b"goto")?;
         self.consume_whitespace(false)?;
         let label = self.consume_identifier()?;
         self.consume_whitespace(false)?;
         self.consume_string(b";")?;
         Ok(h.alloc_goto_statement(|this| GotoStatement { this, position, label, target: None }))
+    }
     fn consume_new_statement(&mut self, h: &mut Heap) -> Result<NewStatementId, ParseError2> {
         let position = self.source.pos();
         self.consume_keyword(b"new")?;
         self.consume_whitespace(false)?;
         let expression = self.consume_call_expression(h)?;
         self.consume_whitespace(false)?;
         self.consume_string(b";")?;
         Ok(h.alloc_new_statement(|this| NewStatement { this, position, expression, next: None }))
+    }
     fn consume_put_statement(&mut self, h: &mut Heap) -> Result<PutStatementId, ParseError2> {
         let position = self.source.pos();
         self.consume_keyword(b"put")?;
         self.consume_whitespace(false)?;
         self.consume_string(b"(")?;
         let port = self.consume_expression(h)?;
         self.consume_whitespace(false)?;
         self.consume_string(b",")?;
         self.consume_whitespace(false)?;
         let message = self.consume_expression(h)?;
         self.consume_whitespace(false)?;
         self.consume_string(b")")?;
         self.consume_whitespace(false)?;
         self.consume_string(b";")?;
         Ok(h.alloc_put_statement(|this| PutStatement { this, position, port, message, next: None }))
+    }
     fn consume_expression_statement(
         &mut self,
         h: &mut Heap,
     ) -> Result<ExpressionStatementId, ParseError2> {
         let position = self.source.pos();
         let expression = self.consume_expression(h)?;
         self.consume_whitespace(false)?;
         self.consume_string(b";")?;
         Ok(h.alloc_expression_statement(|this| ExpressionStatement {
             this,
             position,
             expression,
             next: None,
         }))
+    }
     // ====================
     // Symbol definitions
     // ====================
     fn has_symbol_definition(&self) -> bool {
         self.has_keyword(b"composite")
             || self.has_keyword(b"primitive")
             || self.has_type_keyword()
             || self.has_identifier()
+    }
     fn consume_symbol_definition(&mut self, h: &mut Heap) -> Result<DefinitionId, ParseError2> {
         if self.has_keyword(b"struct") {
             Ok(self.consume_struct_definition(h)?.upcast())
         } else if self.has_keyword(b"enum") {
             Ok(self.consume_enum_definition(h)?.upcast())
         } else if self.has_keyword(b"composite") || self.has_keyword(b"primitive") {
             Ok(self.consume_component_definition(h)?.upcast())
         } else {
             Ok(self.consume_function_definition(h)?.upcast())
+        }
+    }
     fn consume_struct_definition(&mut self, h: &mut Heap) -> Result<StructId, ParseError2> {
         // Parse "struct" keyword, optional polyvars and its identifier
         let struct_pos = self.source.pos();
         self.consume_keyword(b"struct")?;
         self.consume_whitespace(true)?;
         let struct_ident = self.consume_identifier()?;
         let poly_vars = self.consume_polymorphic_vars()?;
         self.consume_whitespace(false)?;
         // Parse struct fields
         self.consume_string(b"{")?;
         let mut next = self.source.next();
         let mut fields = Vec::new();
         while next.is_some() {
             let char = next.unwrap();
             if char == b'}' {
                 break;
+            }
             // Consume field definition
             self.consume_whitespace(false)?;
             let field_position = self.source.pos();
             let field_parser_type = self.consume_type2(h, false)?;
             self.consume_whitespace(true)?;
             let field_ident = self.consume_identifier()?;
             self.consume_whitespace(false)?;
             fields.push(StructFieldDefinition{
                 position: field_position,
                 field: field_ident,
                 parser_type: field_parser_type,
             });
             // If we have a comma, then we may or may not have another field
             // definition. Otherwise we expect the struct to be fully defined
             // and expect a closing brace
             next = self.source.next();
             if let Some(b',') = next {
                 self.source.consume();
                 self.consume_whitespace(false)?;
                 next = self.source.next();
             } else {
                 break;
+            }
+        }
         // End of struct definition, so we expect a closing brace
         self.consume_string(b"}")?;
         // Valid struct definition
         Ok(h.alloc_struct_definition(|this| StructDefinition{
             this,
             position: struct_pos,
             identifier: struct_ident,
             poly_vars,
             fields,
         }))
+    }
     fn consume_enum_definition(&mut self, h: &mut Heap) -> Result<EnumId, ParseError2> {
         // Parse "enum" keyword, optional polyvars and its identifier
         let enum_pos = self.source.pos();
         self.consume_keyword(b"enum")?;
         self.consume_whitespace(true)?;
         let enum_ident = self.consume_identifier()?;
         let poly_vars = self.consume_polymorphic_vars()?;
         self.consume_whitespace(false)?;
         // Parse enum variants
         self.consume_string(b"{")?;
         let mut next = self.source.next();
         let mut variants = Vec::new();
         while next.is_some() {
             let char = next.unwrap();
             if char == b'}' {
                 break;
+            }
             // Consume variant identifier
             self.consume_whitespace(false)?;
             let variant_position = self.source.pos();
             let variant_ident = self.consume_identifier()?;
             self.consume_whitespace(false)?;
             // Consume variant (tag) value: may be nothing, in which case it is
             // assigned automatically, may be a constant integer, or an embedded
             // type as value, resulting in a tagged union
             next = self.source.next();
             let variant_value = if let Some(b',') = next {
                 EnumVariantValue::None
             } else if let Some(b'=') = next {
                 self.source.consume();
                 self.consume_whitespace(false)?;
                 if !self.has_integer() {
                     return Err(self.error_at_pos("expected integer"));
+                }
                 let variant_int = self.consume_integer()?;
                 self.consume_whitespace(false)?;
                 EnumVariantValue::Integer(variant_int)
             } else if let Some(b'(') = next {
                 self.source.consume();
                 self.consume_whitespace(false)?;
                 let variant_type = self.consume_type2(h, false)?;
                 self.consume_whitespace(false)?;
                 self.consume_string(b")")?;
                 self.consume_whitespace(false)?;
                 EnumVariantValue::Type(variant_type)
             } else {
                 return Err(self.error_at_pos("expected ',', '=', or '('"));
             };
             variants.push(EnumVariantDefinition{
                 position: variant_position,
                 identifier: variant_ident,
                 value: variant_value
             });
             // If we have a comma, then we may or may not have another variant,
             // otherwise we expect the enum is fully defined
             next = self.source.next();
             if let Some(b',') = next {
                 self.source.consume();
                 self.consume_whitespace(false)?;
                 next = self.source.next();
             } else {
                 break;
+            }
+        }
         self.consume_string(b"}")?;
         // An enum without variants is somewhat valid, but completely useless
         // within the language
         if variants.is_empty() {
             return Err(ParseError2::new_error(self.source, enum_pos, "enum definition without variants"));
+        }
         Ok(h.alloc_enum_definition(|this| EnumDefinition{
             this,
             position: enum_pos,
             identifier: enum_ident,
             poly_vars,
             variants,
         }))
+    }
     fn consume_component_definition(&mut self, h: &mut Heap) -> Result<ComponentId, ParseError2> {
         // TODO: Cleanup
         if self.has_keyword(b"composite") {
             Ok(self.consume_composite_definition(h)?)
         } else {
             Ok(self.consume_primitive_definition(h)?)
+        }
+    }
     fn consume_composite_definition(&mut self, h: &mut Heap) -> Result<ComponentId, ParseError2> {
         // Parse keyword, optional polyvars and the identifier
         let position = self.source.pos();
         self.consume_keyword(b"composite")?;
         self.consume_whitespace(true)?;
         let identifier = self.consume_identifier()?;
         let poly_vars = self.consume_polymorphic_vars()?;
         self.consume_whitespace(false)?;
         // Consume parameters
         let mut parameters = Vec::new();
         self.consume_parameters(h, &mut parameters)?;
         self.consume_whitespace(false)?;
         // Parse body
         let body = self.consume_block_statement(h)?;
         Ok(h.alloc_component(|this| Component {
             this,
             variant: ComponentVariant::Composite,
             position,
             identifier,
             poly_vars,
             parameters,
             body
         }))
+    }
     fn consume_primitive_definition(&mut self, h: &mut Heap) -> Result<ComponentId, ParseError2> {
         // Consume keyword, optional polyvars and identifier
         let position = self.source.pos();
         self.consume_keyword(b"primitive")?;
         self.consume_whitespace(true)?;
         let identifier = self.consume_identifier()?;
         let poly_vars = self.consume_polymorphic_vars()?;
         self.consume_whitespace(false)?;
         // Consume parameters
         let mut parameters = Vec::new();
         self.consume_parameters(h, &mut parameters)?;
         self.consume_whitespace(false)?;
         // Consume body
         let body = self.consume_block_statement(h)?;
         Ok(h.alloc_component(|this| Component {
             this,
             variant: ComponentVariant::Primitive,
             position,
             identifier,
             poly_vars,
             parameters,
             body
         }))
+    }
     fn consume_function_definition(&mut self, h: &mut Heap) -> Result<FunctionId, ParseError2> {
         // Consume return type, optional polyvars and identifier
         let position = self.source.pos();
         let return_type = self.consume_type2(h, false)?;
         self.consume_whitespace(true)?;
         let identifier = self.consume_identifier()?;
         let poly_vars = self.consume_polymorphic_vars()?;
         self.consume_whitespace(false)?;
         // Consume parameters
         let mut parameters = Vec::new();
         self.consume_parameters(h, &mut parameters)?;
         self.consume_whitespace(false)?;
         // Consume body
         let body = self.consume_block_statement(h)?;
         Ok(h.alloc_function(|this| Function {
             this,
             position,
             return_type,
             identifier,
             poly_vars,
             parameters,
             body,
         }))
+    }
     fn has_pragma(&self) -> bool {
         if let Some(c) = self.source.next() {
             c == b'#'
         } else {
             false
+        }
+    }
     fn consume_pragma(&mut self, h: &mut Heap) -> Result<PragmaId, ParseError2> {
         let position = self.source.pos();
         let next = self.source.next();
         if next != Some(b'#') {
             return Err(self.error_at_pos("Expected pragma"));
+        }
         self.source.consume();
         if !is_vchar(self.source.next()) {
             return Err(self.error_at_pos("Expected pragma"));
+        }
         if self.has_string(b"version") {
             self.consume_string(b"version")?;
             self.consume_whitespace(true)?;
             if !self.has_integer() {
                 return Err(self.error_at_pos("Expected integer constant"));
+            }
             let version = self.consume_integer()?;
             debug_assert!(version >= 0);
             return Ok(h.alloc_pragma(|this| Pragma::Version(PragmaVersion{
                 this, position, version: version as u64
             })))
         } else if self.has_string(b"module") {
             self.consume_string(b"module")?;
             self.consume_whitespace(true)?;
             if !self.has_identifier() {
                 return Err(self.error_at_pos("Expected identifier"));
+            }
             let mut value = Vec::new();
             let mut ident = self.consume_ident()?;
             value.append(&mut ident);
             while self.has_string(b".") {
                 self.consume_string(b".")?;
                 value.push(b'.');
                 ident = self.consume_ident()?;
                 value.append(&mut ident);
+            }
             return Ok(h.alloc_pragma(|this| Pragma::Module(PragmaModule{
                 this, position, value
             })));
         } else {
             return Err(self.error_at_pos("Unknown pragma"));
+        }
+    }
     fn has_import(&self) -> bool {
         self.has_keyword(b"import")
+    }
     fn consume_import(&mut self, h: &mut Heap) -> Result<ImportId, ParseError2> {
         // Parse the word "import" and the name of the module
         let position = self.source.pos();
         self.consume_keyword(b"import")?;
         self.consume_whitespace(true)?;
         let mut value = Vec::new();
         let mut ident = self.consume_ident()?;
         value.append(&mut ident);
         let mut last_ident_start = 0;
         while self.has_string(b".") {
             self.consume_string(b".")?;
             value.push(b'.');
             ident = self.consume_ident()?;
             last_ident_start = value.len();
             value.append(&mut ident);
+        }
         self.consume_whitespace(false)?;
         // Check for the potential aliasing or specific module imports
         let import = if self.has_string(b"as") {
             self.consume_string(b"as")?;
             self.consume_whitespace(true)?;
             let alias = self.consume_ident()?;
             h.alloc_import(|this| Import::Module(ImportModule{
                 this,
                 position,
                 module_name: value,
                 alias,
                 module_id: None,
             }))
         } else if self.has_string(b"::") {
             self.consume_string(b"::")?;
             self.consume_whitespace(false)?;
             if let Some(b'{') = self.source.next() {
                 // Import specific symbols, optionally with an alias
                 self.source.consume();
                 self.consume_whitespace(false)?;
                 let mut symbols = Vec::new();
                 let mut next = self.source.next();
                 while next.is_some() {
                     let char = next.unwrap();
                     if char == b'}' {
                         break;
+                    }
                     let symbol_position = self.source.pos();
                     let symbol_name = self.consume_ident()?;
                     self.consume_whitespace(false)?;
                     if self.has_string(b"as") {
                         // Symbol has an alias
                         self.consume_string(b"as")?;
                         self.consume_whitespace(true)?;
                         let symbol_alias = self.consume_ident()?;
                         symbols.push(AliasedSymbol{
                             position: symbol_position,
                             name: symbol_name,
                             alias: symbol_alias,
                             definition_id: None,
                         });
                     } else {
                         // Symbol does not have an alias
                         symbols.push(AliasedSymbol{
                             position: symbol_position,
                             name: symbol_name.clone(),
                             alias: symbol_name,
                             definition_id: None,
                         });
+                    }
                     // A comma indicates that we may have another symbol coming
                     // up (not necessary), but if not present then we expect the
                     // end of the symbol list
                     self.consume_whitespace(false)?;
                     next = self.source.next();
                     if let Some(b',') = next {
                         self.source.consume();
                         self.consume_whitespace(false)?;
                         next = self.source.next();
                     } else {
                         break;
+                    }
+                }
                 if let Some(b'}') = next {
                     // We are fine, push the imported symbols
                     self.source.consume();
                     if symbols.is_empty() {
                         return Err(ParseError2::new_error(self.source, position, "empty symbol import list"));
+                    }
                     h.alloc_import(|this| Import::Symbols(ImportSymbols{
                         this,
                         position,
                         module_name: value,
                         module_id: None,
                         symbols,
                     }))
                 } else {
                     return Err(self.error_at_pos("Expected '}'"));
+                }
             } else if let Some(b'*') = self.source.next() {
                 // Import all symbols without alias
                 self.source.consume();
                 h.alloc_import(|this| Import::Symbols(ImportSymbols{
                     this,
                     position,
                     module_name: value,
                     module_id: None,
                     symbols: Vec::new()
                 }))
             } else {
                 return Err(self.error_at_pos("Expected '*' or '{'"));
+            }
         } else {
             // No explicit alias or subimports, so implicit alias
             let alias = Vec::from(&value[last_ident_start..]);
             h.alloc_import(|this| Import::Module(ImportModule{
                 this,
                 position,
                 module_name: value,
                 alias,
                 module_id: None,
             }))
         };
         self.consume_whitespace(false)?;
         self.consume_string(b";")?;
         Ok(import)
+    }
     pub fn consume_protocol_description(&mut self, h: &mut Heap) -> Result<RootId, ParseError2> {
         let position = self.source.pos();
         let mut pragmas = Vec::new();
         let mut imports = Vec::new();
         let mut definitions = Vec::new();
         self.consume_whitespace(false)?;
         while self.has_pragma() {
             let pragma = self.consume_pragma(h)?;
             pragmas.push(pragma);
             self.consume_whitespace(false)?;
+        }
         while self.has_import() {
             let import = self.consume_import(h)?;
             imports.push(import);
             self.consume_whitespace(false)?;
+        }
         while self.has_symbol_definition() {
             let def = self.consume_symbol_definition(h)?;
             definitions.push(def);
             self.consume_whitespace(false)?;
+        }
         // end of file
         if !self.source.is_eof() {
             return Err(self.error_at_pos("Expected end of file"));
+        }
         Ok(h.alloc_protocol_description(|this| Root {
             this,
             position,
             pragmas,
             imports,
             definitions,
         }))
+    }
+}
 #[cfg(test)]
 mod tests {
     use crate::protocol::ast::*;
     use crate::protocol::lexer::*;
     use crate::protocol::inputsource::*;
     #[derive(Debug, Eq, PartialEq)]
     enum ParserTypeClass {
         Message, Bool, Byte, Short, Int, Long, String, Array, Nope
+    }
     impl ParserTypeClass {
         fn from(v: &ParserType) -> ParserTypeClass {
             use ParserTypeVariant as PTV;
             use ParserTypeClass as PTC;
             match &v.variant {
                 PTV::Message => PTC::Message,
                 PTV::Bool => PTC::Bool,
                 PTV::Byte => PTC::Byte,
                 PTV::Short => PTC::Short,
                 PTV::Int => PTC::Int,
                 PTV::Long => PTC::Long,
                 PTV::String => PTC::String,
                 PTV::Array(_) => PTC::Array,
                 _ => PTC::Nope,
+            }
+        }
+    }
     #[test]
     fn test_pragmas() {
         let mut h = Heap::new();
         let mut input = InputSource::from_string("
         #version 0o7777
         #module something.dot.separated
         ").expect("new InputSource");
         let mut lex = Lexer::new(&mut input);
         let lexed = lex.consume_protocol_description(&mut h)
             .expect("lex input source");
         let root = &h[lexed];
         assert_eq!(root.pragmas.len(), 2);
         let pv = &h[root.pragmas[0]];
         let pm = &h[root.pragmas[1]];
         if let Pragma::Version(v) = pv {
             assert_eq!(v.version, 0o7777)
         } else {
             assert!(false, "first pragma not version");
+        }
         if let Pragma::Module(m) = pm {
             assert_eq!(m.value, b"something.dot.separated");
         } else {
             assert!(false, "second pragma not module");
+        }
+    }
     #[test]
     fn test_import() {
         let mut h = Heap::new();
         let mut input = InputSource::from_string("
         // Module imports, with optional and explicit aliasing
         import single_module;
         import std.reo;
         import something.other as alias;
         // Symbol imports
         import some_module::*;
         import some_module::{Foo as Bar, Qux, Dix as Flu};
         import std.reo::{
             Foo as Bar, // because thing
             Qux as Mox, // more explanations
             Dix, /* yesh, import me */
         };
         ").unwrap();
         let mut lex = Lexer::new(&mut input);
         let lexed = lex.consume_protocol_description(&mut h).unwrap();
         let root = &h[lexed];
         assert_eq!(root.imports.len(), 6);
         let no_alias_single = h[root.imports[0]].as_module();
         let no_alias_multi = h[root.imports[1]].as_module();
         let with_alias = h[root.imports[2]].as_module();
         assert_eq!(no_alias_single.module_name, b"single_module");
         assert_eq!(no_alias_single.alias, b"single_module");
         assert_eq!(no_alias_multi.module_name, b"std.reo");
         assert_eq!(no_alias_multi.alias, b"reo");
         assert_eq!(with_alias.module_name, b"something.other");
         assert_eq!(with_alias.alias, b"alias");
         let all_symbols = h[root.imports[3]].as_symbols();
         let single_line_symbols = h[root.imports[4]].as_symbols();
         let multi_line_symbols = h[root.imports[5]].as_symbols();
         assert_eq!(all_symbols.module_name, b"some_module");
         assert!(all_symbols.symbols.is_empty());
         assert_eq!(single_line_symbols.module_name, b"some_module");
         assert_eq!(single_line_symbols.symbols.len(), 3);
         assert_eq!(single_line_symbols.symbols[0].name, b"Foo");
         assert_eq!(single_line_symbols.symbols[0].alias, b"Bar");
         assert_eq!(single_line_symbols.symbols[1].name, b"Qux");
         assert_eq!(single_line_symbols.symbols[1].alias, b"Qux");
         assert_eq!(single_line_symbols.symbols[2].name, b"Dix");
         assert_eq!(single_line_symbols.symbols[2].alias, b"Flu");
         assert_eq!(multi_line_symbols.module_name, b"std.reo");
         assert_eq!(multi_line_symbols.symbols.len(), 3);
         assert_eq!(multi_line_symbols.symbols[0].name, b"Foo");
         assert_eq!(multi_line_symbols.symbols[0].alias, b"Bar");
         assert_eq!(multi_line_symbols.symbols[1].name, b"Qux");
         assert_eq!(multi_line_symbols.symbols[1].alias, b"Mox");
         assert_eq!(multi_line_symbols.symbols[2].name, b"Dix");
         assert_eq!(multi_line_symbols.symbols[2].alias, b"Dix");
+    }
     #[test]
     fn test_struct_definition() {
         let mut h = Heap::new();
         let mut input = InputSource::from_string("
         struct Foo {
             byte one,
             short two,
             Bar three,
+        }
         struct Bar{int[] one, int[] two, Qux[] three}
         ").unwrap();
         let mut lex = Lexer::new(&mut input);
         let lexed = lex.consume_protocol_description(&mut h);
         if let Err(err) = &lexed {
             println!("{}", err);
+        }
         let lexed = lexed.unwrap();
         let root = &h[lexed];
         assert_eq!(root.definitions.len(), 2);
         // let symbolic_type = |v: &PrimitiveType| -> Vec<u8> {
         //     if let PrimitiveType::Symbolic(v) = v {
         //         v.identifier.value.clone()
         //     } else {
         //         assert!(false);
         //         unreachable!();
         //     }
         // };
         let foo_def = h[root.definitions[0]].as_struct();
         assert_eq!(foo_def.identifier.value, b"Foo");
         assert_eq!(foo_def.fields.len(), 3);
         assert_eq!(foo_def.fields[0].field.value, b"one");
         assert_eq!(ParserTypeClass::from(&h[foo_def.fields[0].parser_type]), ParserTypeClass::Byte);
         assert_eq!(foo_def.fields[1].field.value, b"two");
         assert_eq!(ParserTypeClass::from(&h[foo_def.fields[1].parser_type]), ParserTypeClass::Short);
         assert_eq!(foo_def.fields[2].field.value, b"three");
         // assert_eq!(
         //     symbolic_type(&h[foo_def.fields[2].the_type].the_type.primitive),
         //     Vec::from("Bar".as_bytes())
         // );
         let bar_def = h[root.definitions[1]].as_struct();
         assert_eq!(bar_def.identifier.value, b"Bar");
         assert_eq!(bar_def.fields.len(), 3);
         assert_eq!(bar_def.fields[0].field.value, b"one");
         assert_eq!(ParserTypeClass::from(&h[bar_def.fields[0].parser_type]), ParserTypeClass::Array);
         assert_eq!(bar_def.fields[1].field.value, b"two");
         assert_eq!(ParserTypeClass::from(&h[bar_def.fields[1].parser_type]), ParserTypeClass::Array);
         assert_eq!(bar_def.fields[2].field.value, b"three");
         assert_eq!(ParserTypeClass::from(&h[bar_def.fields[2].parser_type]), ParserTypeClass::Array);
         // assert_eq!(
         //     symbolic_type(&h[bar_def.fields[2].parser_type].the_type.primitive),
         //     Vec::from("Qux".as_bytes())
         // );
+    }
     #[test]
     fn test_enum_definition() {
         let mut h = Heap::new();
         let mut input = InputSource::from_string("
         enum Foo {
             A = 0,
             B = 5,
             C,
             D = 0xFF,
+        }
         enum Bar { Ayoo, Byoo, Cyoo,}
         enum Qux { A(byte[]), B(Bar[]), C(byte)
+        }
         ").unwrap();
         let mut lex = Lexer::new(&mut input);
         let lexed = lex.consume_protocol_description(&mut h).unwrap();
         let root = &h[lexed];
         assert_eq!(root.definitions.len(), 3);
         let foo_def = h[root.definitions[0]].as_enum();
         assert_eq!(foo_def.identifier.value, b"Foo");
         assert_eq!(foo_def.variants.len(), 4);
         assert_eq!(foo_def.variants[0].identifier.value, b"A");
         assert_eq!(foo_def.variants[0].value, EnumVariantValue::Integer(0));
         assert_eq!(foo_def.variants[1].identifier.value, b"B");
         assert_eq!(foo_def.variants[1].value, EnumVariantValue::Integer(5));
         assert_eq!(foo_def.variants[2].identifier.value, b"C");
         assert_eq!(foo_def.variants[2].value, EnumVariantValue::None);
         assert_eq!(foo_def.variants[3].identifier.value, b"D");
         assert_eq!(foo_def.variants[3].value, EnumVariantValue::Integer(0xFF));
         let bar_def = h[root.definitions[1]].as_enum();
         assert_eq!(bar_def.identifier.value, b"Bar");
         assert_eq!(bar_def.variants.len(), 3);
         assert_eq!(bar_def.variants[0].identifier.value, b"Ayoo");
         assert_eq!(bar_def.variants[0].value, EnumVariantValue::None);
         assert_eq!(bar_def.variants[1].identifier.value, b"Byoo");
         assert_eq!(bar_def.variants[1].value, EnumVariantValue::None);
         assert_eq!(bar_def.variants[2].identifier.value, b"Cyoo");
         assert_eq!(bar_def.variants[2].value, EnumVariantValue::None);
         let qux_def = h[root.definitions[2]].as_enum();
         let enum_type = |value: &EnumVariantValue| -> &ParserType {
             if let EnumVariantValue::Type(t) = value {
                 &h[*t]
             } else {
                 assert!(false);
                 unreachable!();
+            }
         };
         assert_eq!(qux_def.identifier.value, b"Qux");
         assert_eq!(qux_def.variants.len(), 3);
         assert_eq!(qux_def.variants[0].identifier.value, b"A");
         assert_eq!(ParserTypeClass::from(enum_type(&qux_def.variants[0].value)), ParserTypeClass::Array);
         assert_eq!(qux_def.variants[1].identifier.value, b"B");
         assert_eq!(ParserTypeClass::from(enum_type(&qux_def.variants[1].value)), ParserTypeClass::Array);
         // if let PrimitiveType::Symbolic(t) = &enum_type(&qux_def.variants[1].value).the_type.primitive {
         //     assert_eq!(t.identifier.value, Vec::from("Bar".as_bytes()));
         // } else { assert!(false) }
         assert_eq!(qux_def.variants[2].identifier.value, b"C");
         assert_eq!(ParserTypeClass::from(enum_type(&qux_def.variants[2].value)), ParserTypeClass::Byte);
+    }
 //     #[test]
 //     fn test_lowercase() {
 //         assert_eq!(lowercase(b'a'), b'a');
 //         assert_eq!(lowercase(b'A'), b'a');
 //         assert_eq!(lowercase(b'z'), b'z');
 //         assert_eq!(lowercase(b'Z'), b'z');
 //     }
 //     #[test]
 //     fn test_basic_expression() {
 //         let mut h = Heap::new();
 //         let mut is = InputSource::from_string("a+b;").unwrap();
 //         let mut lex = Lexer::new(&mut is);
 //         match lex.consume_expression(&mut h) {
 //             Ok(expr) => {
 //                 println!("{:?}", expr);
 //                 if let Binary(bin) = &h[expr] {
 //                     if let Variable(left) = &h[bin.left] {
 //                         if let Variable(right) = &h[bin.right] {
 //                             assert_eq!("a", format!("{}", h[left.identifier]));
 //                             assert_eq!("b", format!("{}", h[right.identifier]));
 //                             assert_eq!(Some(b';'), is.next());
 //                             return;
 //                         }
 //                     }
 //                 }
 //                 assert!(false);
 //             }
 //             Err(err) => {
 //                 err.print(&is);
 //                 assert!(false);
 //             }
 //         }
 //     }
 //     #[test]
 //     fn test_paren_expression() {
 //         let mut h = Heap::new();
 //         let mut is = InputSource::from_string("(true)").unwrap();
 //         let mut lex = Lexer::new(&mut is);
 //         match lex.consume_paren_expression(&mut h) {
 //             Ok(expr) => {
 //                 println!("{:#?}", expr);
 //                 if let Constant(con) = &h[expr] {
 //                     if let ast::Constant::True = con.value {
 //                         return;
 //                     }
 //                 }
 //                 assert!(false);
 //             }
 //             Err(err) => {
 //                 err.print(&is);
 //                 assert!(false);
 //             }
 //         }
 //     }
 //     #[test]
 //     fn test_expression() {
 //         let mut h = Heap::new();
 //         let mut is = InputSource::from_string("(x(1+5,get(y))-w[5])+z++\n").unwrap();
 //         let mut lex = Lexer::new(&mut is);
 //         match lex.consume_expression(&mut h) {
 //             Ok(expr) => {
 //                 println!("{:#?}", expr);
 //             }
 //             Err(err) => {
 //                 err.print(&is);
 //                 assert!(false);
 //             }
 //         }
 //     }
 //     #[test]
 //     fn test_basic_statement() {
 //         let mut h = Heap::new();
 //         let mut is = InputSource::from_string("while (true) { skip; }").unwrap();
 //         let mut lex = Lexer::new(&mut is);
 //         match lex.consume_statement(&mut h) {
 //             Ok(stmt) => {
 //                 println!("{:#?}", stmt);
 //                 if let Statement::While(w) = &h[stmt] {
 //                     if let Expression::Constant(_) = h[w.test] {
 //                         if let Statement::Block(_) = h[w.body] {
 //                             return;
 //                         }
 //                     }
 //                 }
 //                 assert!(false);
 //             }
 //             Err(err) => {
 //                 err.print(&is);
 //                 assert!(false);
 //             }
 //         }
 //     }
 //     #[test]
 //     fn test_statement() {
 //         let mut h = Heap::new();
 //         let mut is = InputSource::from_string(
 //             "label: while (true) { if (x++ > y[0]) break label; else continue; }\n",
 //         )
 //         .unwrap();
 //         let mut lex = Lexer::new(&mut is);
 //         match lex.consume_statement(&mut h) {
 //             Ok(stmt) => {
 //                 println!("{:#?}", stmt);
 //             }
 //             Err(err) => {
 //                 err.print(&is);
 //                 assert!(false);
 //             }
 //         }
 //     }
+}

src/protocol/parser/type_resolver.rs

➞

Show inline comments

 use std::collections::{HashMap, HashSet, VecDeque};
 use crate::protocol::ast::*;
 use crate::protocol::inputsource::*;
 use super::type_table::*;
 use super::symbol_table::*;
 use super::visitor::{
     STMT_BUFFER_INIT_CAPACITY,
     EXPR_BUFFER_INIT_CAPACITY,
     Ctx,
     Visitor2,
     VisitorResult
 };
 use std::collections::hash_map::Entry;
 const BOOL_TEMPLATE: [InferenceTypePart; 1] = [ InferenceTypePart::Bool ];
 const NUMBERLIKE_TEMPLATE: [InferenceTypePart; 1] = [ InferenceTypePart::NumberLike ];
 const INTEGERLIKE_TEMPLATE: [InferenceTypePart; 1] = [ InferenceTypePart::IntegerLike ];
 const ARRAY_TEMPLATE: [InferenceTypePart; 2] = [ InferenceTypePart::Array, InferenceTypePart::Unknown ];
 const ARRAYLIKE_TEMPLATE: [InferenceTypePart; 2] = [ InferenceTypePart::ArrayLike, InferenceTypePart::Unknown ];
 const PORTLIKE_TEMPLATE: [InferenceTypePart; 2] = [ InferenceTypePart::PortLike, InferenceTypePart::Unknown ];
 /// TODO: @performance Turn into PartialOrd+Ord to simplify checks
 #[derive(Debug, Clone, Eq, PartialEq)]
 pub(crate) enum InferenceTypePart {
     // A marker with an identifier which we can use to seek subsections of the
     // inferred type
     Marker(usize),
     // 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
     Message,
     Bool,
     Byte,
     Short,
     Int,
     Long,
     String,
     // One subtype
     Array,
     Slice,
     Input,
     Output,
     // A user-defined type with any number of subtypes
     Instance(DefinitionId, usize)
+}
 impl InferenceTypePart {
     fn is_marker(&self) -> bool {
         if let InferenceTypePart::Marker(_) = self { true } else { 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 => false,
+            ITP::Unknown | ITP::NumberLike | ITP::IntegerLike | ITP::ArrayLike | ITP::PortLike => false,
             _ => true
+        }
+    }
     fn is_concrete_number(&self) -> bool {
         // TODO: @float
         use InferenceTypePart as ITP;
         match self {
             ITP::Byte | ITP::Short | ITP::Int | ITP::Long => true,
             _ => false,
+        }
+    }
     fn is_concrete_integer(&self) -> bool {
         use InferenceTypePart as ITP;
         match self {
             ITP::Byte | ITP::Short | ITP::Int | ITP::Long => true,
             _ => false,
+        }
+    }
     fn is_concrete_array_or_slice(&self) -> bool {
         use InferenceTypePart as ITP;
         match self {
             ITP::Array | ITP::Slice => true,
             _ => false,
+        }
+    }
     fn is_concrete_port(&self) -> bool {
         use InferenceTypePart as ITP;
         match self {
             ITP::Input | ITP::Output => true,
             _ => false,
+        }
+    }
     /// 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::Message | ITP::Bool |
             ITP::Byte | ITP::Short | ITP::Int | ITP::Long |
             ITP::String => {
                 -1
             },
             ITP::Marker(_) | ITP::ArrayLike | ITP::Array | ITP::Slice |
             ITP::Input | ITP::Output => {
+            ITP::PortLike | ITP::Input | ITP::Output => {
                 // One subtype, so do not modify depth
             },
             ITP::Instance(_, num_args) => {
                 (*num_args as i32) - 1
+            }
+        }
+    }
+}
 impl From<ConcreteTypeVariant> for InferenceTypePart {
     fn from(v: ConcreteTypeVariant) -> InferenceTypePart {
         use ConcreteTypeVariant as CTV;
         use InferenceTypePart as ITP;
         match v {
             CTV::Message => ITP::Message,
             CTV::Bool => ITP::Bool,
             CTV::Byte => ITP::Byte,
             CTV::Short => ITP::Short,
             CTV::Int => ITP::Int,
             CTV::Long => ITP::Long,
             CTV::String => ITP::String,
             CTV::Array => ITP::Array,
             CTV::Slice => ITP::Slice,
             CTV::Input => ITP::Input,
             CTV::Output => ITP::Output,
             CTV::Instance(id, num) => ITP::Instance(id, num),
+        }
+    }
+}
 struct InferenceType {
     has_marker: bool,
     is_done: bool,
     parts: Vec<InferenceTypePart>,
+}
 impl InferenceType {
     fn new(has_marker: bool, is_done: bool, parts: Vec<InferenceTypePart>) -> Self {
         if cfg!(debug_assertions) {
             debug_assert(!parts.is_empty());
+            debug_assert!(!parts.is_empty());
             if !has_marker {
                 debug_assert!(parts.iter().all(|v| !v.is_marker()));
+            }
             if is_done {
                 debug_assert!(parts.iter().all(|v| v.is_concrete()));
+            }
+        }
         Self{ has_marker, is_done, parts }
+    }
     // TODO: @performance, might all be done inline in the type inference methods
     fn recompute_is_done(&mut self) {
-        self.done = self.parts.iter().all(|v| v.is_concrete());
+        self.is_done = self.parts.iter().all(|v| v.is_concrete());
+    }
     /// Checks if type is, or may be inferred as, a number
     // TODO: @float
     fn might_be_number(&self) -> bool {
         use InferenceTypePart as ITP;
         // TODO: @marker?
         if self.parts.len() != 1 { return false; }
         match self.parts[0] {
             ITP::Unknown | ITP::NumberLike | ITP::IntegerLike |
             ITP::Byte | ITP::Short | ITP::Int | ITP::Long =>
                 true,
             _ =>
                 false,
+        }
+    }
     /// Checks if type is, or may be inferred as, an integer
     fn might_be_integer(&self) -> bool {
         use InferenceTypePart as ITP;
         // TODO: @marker?
         if self.parts.len() != 1 { return false; }
         match self.parts[0] {
             ITP::Unknown | ITP::IntegerLike |
             ITP::Byte | ITP::Short | ITP::Int | ITP::Long =>
                 true,
             _ =>
                 false,
+        }
+    }
     /// Checks if type is, or may be inferred as, a boolean
     fn might_be_boolean(&self) -> bool {
         use InferenceTypePart as ITP;
         // TODO: @marker?
         if self.parts.len() != 1 { return false; }
         match self.parts[0] {
             ITP::Unknown | ITP::Bool => true,
             _ => false
+        }
+    }
     fn marker_iter(&self) -> InferenceTypeMarkerIter {
         InferenceTypeMarkerIter::new(&self.parts)
+    }
     /// Given that the `parts` are a depth-first serialized tree of types, this
     /// function finds the subtree anchored at a specific node. The returned
     /// index is exclusive.
     fn find_subtree_end_idx(parts: &[InferenceTypePart], start_idx: usize) -> usize {
         let mut depth = 1;
         let mut idx = start_idx;
         while idx < parts.len() {
             depth += parts[idx].depth_change();
             if depth == 0 {
                 return idx + 1;
+            }
             idx += 1;
+        }
         // If here, then the inference type is malformed
         unreachable!();
+    }
     /// Call that attempts to infer the part at `to_infer.parts[to_infer_idx]`
     /// using the subtree at `template.parts[template_idx]`. Will return
     /// `Some(depth_change_due_to_traversal)` if type inference has been
     /// applied. In this case the indices will also be modified to point to the
     /// next part in both templates. If type inference has not (or: could not)
     /// be applied then `None` will be returned. Note that this might mean that
     /// the types are incompatible.
     ///
     /// As this is a helper functions, some assumptions: the parts are not
     /// exactly equal, and neither of them contains a marker.
     fn infer_part_for_single_type(
         to_infer: &mut InferenceType, to_infer_idx: &mut usize,
         template_parts: &[InferenceTypePart], template_idx: &mut usize,
     ) -> Option<i32> {
         use InferenceTypePart as ITP;
         let to_infer_part = &to_infer.parts[*to_infer_idx];
         let template_part = &template_parts[*template_idx];
         // Check for programmer mistakes
         if cfg!(debug_assertions) {
             debug_assert_ne!(to_infer_part, template_part);
             if let ITP::Marker(_) = to_infer_part {
                 debug_assert!(false, "marker encountered in 'infer part'");
+            }
             if let ITP::Marker(_) = template_part {
                 debug_assert!(false, "marker encountered in 'infer part'");
+            }
+        }
         // Inference of a somewhat-specified type
-        if (*to_infer_part == ITP::IntegerLike && template_part.is_concrete_int()) ||
+        if (*to_infer_part == ITP::IntegerLike && template_part.is_concrete_integer()) ||
             (*to_infer_part == ITP::NumberLike && template_part.is_concrete_number()) ||
             (*to_infer_part == ITP::ArrayLike && template_part.is_concrete_array_or_slice())
             (*to_infer_part == ITP::NumberLike && *template_part == ITP::IntegerLike) ||
             (*to_infer_part == ITP::ArrayLike && template_part.is_concrete_array_or_slice()) ||
             (*to_infer_part == ITP::PortLike && template_part.is_concrete_port())
+        {
             let depth_change = to_infer_part.depth_change();
             debug_assert_eq!(depth_change, template_part.depth_change());
             to_infer.parts[*to_infer_idx] = template_part.clone();
             *to_infer_idx += 1;
             *template_idx += 1;
             return Some(depth_change);
+        }
         // Inference of a completely unknown type
         if *to_infer_part == ITP::Unknown {
             // template part is different, so cannot be unknown, hence copy the
             // entire subtree
             let template_end_idx = Self::find_subtree_end_idx(template_parts, *template_idx);
             to_infer.parts[*to_infer_idx] = template_part.clone();
             *to_infer_idx += 1;
             for insert_idx in (*template_idx + 1)..template_end_idx {
                 to_infer.parts.insert(*to_infer_idx, template_parts[insert_idx].clone());
                 *to_infer_idx += 1;
+            }
             *template_idx = template_end_idx;
             // Note: by definition the LHS was Unknown and the RHS traversed a
             // full subtree.
             return Some(-1);
+        }
         None
+    }
     /// Attempts to infer types between two `InferenceType` instances. This
     /// function is unsafe as it accepts pointers to work around Rust's
     /// borrowing rules. The caller must ensure that the pointers are distinct.
     unsafe fn infer_subtrees_for_both_types(
         type_a: *mut InferenceType, start_idx_a: usize,
         type_b: *mut InferenceType, start_idx_b: usize
     ) -> DualInferenceResult {
         use InferenceTypePart as ITP;
         debug_assert!(!std::ptr::eq(type_a, type_b), "same inference types");
         let type_a = &mut *type_a;
         let type_b = &mut *type_b;
         let mut modified_a = false;
         let mut modified_b = false;
         let mut idx_a = start_idx_a;
         let mut idx_b = start_idx_b;
         let mut depth = 1;
         while depth > 0 {
             // Advance indices if we encounter markers or equal parts
             let part_a = &type_a.parts[idx_a];
             let part_b = &type_b.parts[idx_b];
             if part_a == part_b {
                 depth += part_a.depth_change();
                 debug_assert_eq!(depth, part_b.depth_change());
                 idx_a += 1;
                 idx_b += 1;
                 continue;
+            }
             if let ITP::Marker(_) = part_a { idx_a += 1; continue; }
             if let ITP::Marker(_) = part_b { idx_b += 1; continue; }
             // Types are not equal and are both not markers
             if let Some(depth_change) = Self::infer_part_for_single_type(type_a, &mut idx_a, &type_b.parts, &mut idx_b) {
                 depth += depth_change;
                 modified_a = true;
                 continue;
+            }
             if let Some(depth_change) = Self::infer_part_for_single_type(type_b, &mut idx_b, &type_a.parts, &mut idx_a) {
                 depth += depth_change;
                 modified_b = true;
                 continue;
+            }
             // And can also not be inferred in any way: types must be incompatible
             return DualInferenceResult::Incompatible;
+        }
         if modified_a { type_a.recompute_is_done(); }
         if modified_b { type_b.recompute_is_done(); }
         // If here then we completely inferred the subtrees.
         match (modified_a, modified_b) {
             (false, false) => DualInferenceResult::Neither,
             (false, true) => DualInferenceResult::Second,
             (true, false) => DualInferenceResult::First,
             (true, true) => DualInferenceResult::Both
+        }
+    }
     /// Attempts to infer the first subtree based on the template. Like
     /// `infer_subtrees_for_both_types`, but now only applying inference to
     /// `to_infer` based on the type information in `template`.
     /// Secondary use is to make sure that a type follows a certain template.
     fn infer_subtree_for_single_type(
         to_infer: &mut InferenceType, mut to_infer_idx: usize,
         template: &[InferenceTypePart], mut template_idx: usize,
     ) -> SingleInferenceResult {
         use InferenceTypePart as ITP;
         let mut modified = false;
         let mut depth = 1;
         while depth > 0 {
             let to_infer_part = &to_infer.parts[to_infer_idx];
-            let template_part = &template.parts[template_idx];
             let template_part = &template[template_idx];
-            if part_a == part_b {
+            if to_infer_part == template_part {
                 depth += to_infer_part.depth_change();
-                debug_assert!(depth, template_part.depth_change());
+                debug_assert_eq!(depth, template_part.depth_change());
                 to_infer_idx += 1;
                 template_idx += 1;
                 continue;
+            }
             if let ITP::Marker(_) = to_infer_part { to_infer_idx += 1; continue; }
             if let ITP::Marker(_) = template_part { to_infer_idx += 1; continue; }
             // Types are not equal and not markers
             if let Some(depth_change) = Self::infer_part_for_single_type(
                 to_infer, &mut to_infer_idx, template, &mut template_idx
             ) {
                 depth += depth_change;
                 modified = true;
                 continue;
+            }
             // The template might contain partially known types, so check for
             // these and allow them
             if *template_part == ITP::Unknown {
                 to_infer_idx = Self::find_subtree_end_idx(&to_infer.parts, to_infer_idx);
                 template_idx += 1;
                 continue;
+            }
             if (*template_part == ITP::NumberLike && (*to_infer_part == ITP::IntegerLike || to_infer_part.is_concrete_number())) ||
                 (*template_part == ITP::IntegerLike && to_infer_part.is_concrete_integer()) ||
                 (*template_part == ITP::ArrayLike && to_infer_part.is_concrete_array_or_slice()) ||
                 (*template_part == ITP::PortLike && (*to_infer_part == ITP::PortLike || to_infer_part.is_concrete_port()))
+            {
                 to_infer_idx += 1;
                 template_idx += 1;
                 continue;
+            }
             return SingleInferenceResult::Incompatible
+        }
         return if modified {
             to_infer.recompute_is_done();
             SingleInferenceResult::Modified
         } else {
             SingleInferenceResult::Unmodified
+        }
+    }
     /// Returns a human-readable version of the type. Only use for debugging
     /// or returning errors (since it allocates a string).
     fn display_name(&self, heap: &Heap) -> String {
-        use InferredPart as IP;
+        use InferenceTypePart as ITP;
         fn write_recursive(v: &mut String, t: &InferenceType, h: &Heap, idx: &mut usize) {
             match &t.parts[*idx] {
                 IP::Unknown => v.push_str("?"),
                 IP::Void => v.push_str("void"),
                 IP::IntegerLike => v.push_str("int?"),
                 IP::Message => v.push_str("msg"),
                 IP::Bool => v.push_str("bool"),
                 IP::Byte => v.push_str("byte"),
                 IP::Short => v.push_str("short"),
                 IP::Int => v.push_str("int"),
                 IP::Long => v.push_str("long"),
                 IP::String => v.push_str("str"),
                 IP::ArrayLike => {
                 ITP::Marker(_) => {},
                 ITP::Unknown => v.push_str("?"),
                 ITP::NumberLike => v.push_str("num?"),
                 ITP::IntegerLike => v.push_str("int?"),
                 ITP::ArrayLike => {
                     *idx += 1;
                     write_recursive(v, t, h, idx);
                     v.push_str("[?]");
                 },
                 ITP::PortLike => {
                     *idx += 1;
                     v.push_str("port?<");
                     write_recursive(v, t, h, idx);
                     v.push('>');
+                }
                 IP::Array => {
                 ITP::Void => v.push_str("void"),
                 ITP::Message => v.push_str("msg"),
                 ITP::Bool => v.push_str("bool"),
                 ITP::Byte => v.push_str("byte"),
                 ITP::Short => v.push_str("short"),
                 ITP::Int => v.push_str("int"),
                 ITP::Long => v.push_str("long"),
                 ITP::String => v.push_str("str"),
                 ITP::Array => {
                     *idx += 1;
                     write_recursive(v, t, h, idx);
                     v.push_str("[]");
                 },
-                IP::Slice => {
+                ITP::Slice => {
                     *idx += 1;
                     write_recursive(v, t, h, idx);
                     v.push_str("[..]")
                 },
-                IP::Input => {
+                ITP::Input => {
                     *idx += 1;
                     v.push_str("in<");
                     write_recursive(v, t, h, idx);
                     v.push('>');
                 },
-                IP::Output => {
+                ITP::Output => {
                     *idx += 1;
                     v.push_str("out<");
                     write_recursive(v, t, h, idx);
                     v.push('>');
                 },
-                IP::Instance(definition_id, num_sub) => {
+                ITP::Instance(definition_id, num_sub) => {
                     let definition = &h[*definition_id];
                     v.push_str(&String::from_utf8_lossy(&definition.identifier().value));
                     if *num_sub > 0 {
                         v.push('<');
                         *idx += 1;
                         write_recursive(v, t, h, idx);
                         for _sub_idx in 1..*num_sub {
                             *idx += 1;
                             v.push_str(", ");
                             write_recursive(v, t, h, idx);
+                        }
                         v.push('>');
+                    }
                 },
+            }
+        }
         let mut buffer = String::with_capacity(self.parts.len() * 5);
         let mut idx = 0;
         write_recursive(&mut buffer, self, heap, &mut idx);
         buffer
+    }
+}
 /// Iterator over the subtrees that follow a marker in an `InferenceType`
 /// instance
 struct InferenceTypeMarkerIter<'a> {
     parts: &'a [InferenceTypePart],
     idx: usize,
+}
 impl<'a> InferenceTypeMarkerIter<'a> {
     fn new(parts: &'a [InferenceTypePart]) -> Self {
         Self{ parts, idx: 0 }
+    }
+}
 impl<'a> Iterator for InferenceTypeMarkerIter<'a> {
     type Item = (usize, &'a [InferenceTypePart]);
     fn next(&mut self) -> Option<Self::Item> {
         // Iterate until we find a marker
         while self.idx < self.parts.len() {
             if let InferenceTypePart::Marker(marker) = self.parts[self.idx] {
                 // Found a marker, find the subtree end
                 let start_idx = self.idx + 1;
                 let end_idx = InferenceType::find_subtree_end_idx(self.parts, start_idx);
                 // Modify internal index, then return items
                 self.idx = end_idx;
                 return Some((marker, &self.parts[start_idx..end_idx]))
+            }
             self.idx += 1;
+        }
         None
+    }
+}
 /// Extra data needed to fully resolve polymorphic types. Each argument contains
 /// "markers" with an index corresponding to the polymorphic variable. Hence if
 /// we advance any of the inference types with markers then we need to compare
 /// them against the polymorph type. If the polymorph type is then progressed
 /// then we need to apply that to all arguments that contain that polymorphic
 /// type.
 struct PolymorphInferenceType {
     definition: DefinitionId,
     poly_vars: Vec<InferenceType>,
     arguments: Vec<InferenceType>,
     return_type: InferenceType,
+}
 #[derive(PartialEq, Eq)]
 enum DualInferenceResult {
     Neither,        // neither argument is clarified
     First,          // first argument is clarified using the second one
     Second,         // second argument is clarified using the first one
     Both,           // both arguments are clarified
     Incompatible,   // types are incompatible: programmer error
+}
 impl DualInferenceResult {
     fn modified_any(&self) -> bool {
         match self {
             DualInferenceResult::First | DualInferenceResult::Second | DualInferenceResult::Both => true,
             _ => false
+        }
+    }
     fn modified_lhs(&self) -> bool {
         match self {
             DualInferenceResult::First | DualInferenceResult::Both => true,
             _ => false
+        }
+    }
     fn modified_rhs(&self) -> bool {
         match self {
             DualInferenceResult::Second | DualInferenceResult::Both => true,
             _ => false
+        }
+    }
+}
 #[derive(PartialEq, Eq)]
 enum SingleInferenceResult {
     Unmodified,
     Modified,
     Incompatible
+}
 enum DefinitionType{
     None,
     Component(ComponentId),
     Function(FunctionId),
+}
 /// This particular visitor will recurse depth-first into the AST and ensures
 /// that all expressions have the appropriate types. At the moment this implies:
 ///
 ///     - Type checking arguments to unary and binary operators.
 ///     - Type checking assignment, indexing, slicing and select expressions.
 ///     - Checking arguments to functions and component instantiations.
 ///
 /// This will be achieved by slowly descending into the AST. At any given
 /// expression we may depend on
 pub(crate) struct TypeResolvingVisitor {
     definition_type: DefinitionType,
     // Buffers for iteration over substatements and subexpressions
     stmt_buffer: Vec<StatementId>,
     expr_buffer: Vec<ExpressionId>,
     // If instantiating a monomorph of a polymorphic proctype, then we store the
     // values of the polymorphic values here. There should be as many, and in
     // the same order as, in the definition's polyargs.
     polyvars: Vec<ConcreteType>,
     // Mapping from parser type to inferred type. We attempt to continue to
     // specify these types until we're stuck or we've fully determined the type.
     infer_types: HashMap<VariableId, InferenceType>,
     expr_types: HashMap<ExpressionId, InferenceType>,
     extra_data: HashMap<ExpressionId, ExtraData>,
     expr_queued: HashSet<ExpressionId>,
+}
 // TODO: @rename used for calls and struct literals, maybe union literals?
 struct ExtraData {
     /// Progression of polymorphic variables (if any)
     poly_vars: Vec<InferenceType>,
     /// Progression of types of call arguments or struct members
     embedded: Vec<InferenceType>,
     returned: InferenceType,
+}
 impl TypeResolvingVisitor {
     pub(crate) fn new() -> Self {
         TypeResolvingVisitor{
             definition_type: DefinitionType::None,
             stmt_buffer: Vec::with_capacity(STMT_BUFFER_INIT_CAPACITY),
             expr_buffer: Vec::with_capacity(EXPR_BUFFER_INIT_CAPACITY),
             polyvars: Vec::new(),
             infer_types: HashMap::new(),
             expr_types: HashMap::new(),
             extra_data: HashMap::new(),
             expr_queued: HashSet::new(),
+        }
+    }
     fn reset(&mut self) {
         self.definition_type = DefinitionType::None;
         self.stmt_buffer.clear();
         self.expr_buffer.clear();
         self.polyvars.clear();
         self.infer_types.clear();
         self.expr_types.clear();
+    }
+}
 impl Visitor2 for TypeResolvingVisitor {
     // Definitions
     fn visit_component_definition(&mut self, ctx: &mut Ctx, id: ComponentId) -> VisitorResult {
         self.reset();
         self.definition_type = DefinitionType::Component(id);
         let comp_def = &ctx.heap[id];
         debug_assert_eq!(comp_def.poly_vars.len(), self.polyvars.len(), "component polyvars do not match imposed polyvars");
         for param_id in comp_def.parameters.clone() {
             let param = &ctx.heap[param_id];
             let infer_type = self.determine_inference_type_from_parser_type(ctx, param.parser_type);
             debug_assert!(infer_type.done, "expected component arguments to be concrete types");
             let infer_type = self.determine_inference_type_from_parser_type(ctx, param.parser_type, true);
             debug_assert!(infer_type.is_done, "expected component arguments to be concrete types");
             self.infer_types.insert(param_id.upcast(), infer_type);
+        }
         let body_stmt_id = ctx.heap[id].body;
         self.visit_stmt(ctx, body_stmt_id)
+    }
     fn visit_function_definition(&mut self, ctx: &mut Ctx, id: FunctionId) -> VisitorResult {
         self.reset();
         self.definition_type = DefinitionType::Function(id);
         let func_def = &ctx.heap[id];
         debug_assert_eq!(func_def.poly_vars.len(), self.polyvars.len(), "function polyvars do not match imposed polyvars");
         for param_id in func_def.parameters.clone() {
             let param = &ctx.heap[param_id];
             let infer_type = self.determine_inference_type_from_parser_type(ctx, param.parser_type);
             debug_assert!(infer_type.done, "expected function arguments to be concrete types");
             let infer_type = self.determine_inference_type_from_parser_type(ctx, param.parser_type, true);
             debug_assert!(infer_type.is_done, "expected function arguments to be concrete types");
             self.infer_types.insert(param_id.upcast(), infer_type);
+        }
         let body_stmt_id = ctx.heap[id].body;
         self.visit_stmt(ctx, body_stmt_id)
+    }
     // Statements
     fn visit_block_stmt(&mut self, ctx: &mut Ctx, id: BlockStatementId) -> VisitorResult {
         // Transfer statements for traversal
         let block = &ctx.heap[id];
         for stmt_id in block.statements.clone() {
             self.visit_stmt(ctx, stmt_id);
+        }
         Ok(())
+    }
     fn visit_local_memory_stmt(&mut self, ctx: &mut Ctx, id: MemoryStatementId) -> VisitorResult {
         let memory_stmt = &ctx.heap[id];
         let local = &ctx.heap[memory_stmt.variable];
         let infer_type = self.determine_inference_type_from_parser_type(ctx, local.parser_type);
+        let infer_type = self.determine_inference_type_from_parser_type(ctx, local.parser_type, true);
         self.infer_types.insert(memory_stmt.variable.upcast(), infer_type);
         let expr_id = memory_stmt.initial;
         self.visit_expr(ctx, expr_id)?;
         Ok(())
+    }
     fn visit_local_channel_stmt(&mut self, ctx: &mut Ctx, id: ChannelStatementId) -> VisitorResult {
         let channel_stmt = &ctx.heap[id];
         let from_local = &ctx.heap[channel_stmt.from];
         let from_infer_type = self.determine_inference_type_from_parser_type(ctx, from_local.parser_type);
+        let from_infer_type = self.determine_inference_type_from_parser_type(ctx, from_local.parser_type, true);
         self.infer_types.insert(from_local.this.upcast(), from_infer_type);
         let to_local = &ctx.heap[channel_stmt.to];
         let to_infer_type = self.determine_inference_type_from_parser_type(ctx, to_local.parser_type);
+        let to_infer_type = self.determine_inference_type_from_parser_type(ctx, to_local.parser_type, true);
         self.infer_types.insert(to_local.this.upcast(), to_infer_type);
         Ok(())
+    }
     fn visit_labeled_stmt(&mut self, ctx: &mut Ctx, id: LabeledStatementId) -> VisitorResult {
         let labeled_stmt = &ctx.heap[id];
         let substmt_id = labeled_stmt.body;
         self.visit_stmt(ctx, substmt_id)
+    }
     fn visit_if_stmt(&mut self, ctx: &mut Ctx, id: IfStatementId) -> VisitorResult {
         let if_stmt = &ctx.heap[id];
         let true_body_id = if_stmt.true_body;
         let false_body_id = if_stmt.false_body;
         let test_expr_id = if_stmt.test;
         self.visit_expr(ctx, test_expr_id)?;
         self.visit_stmt(ctx, true_body_id)?;
         self.visit_stmt(ctx, false_body_id)?;
         Ok(())
+    }
     fn visit_while_stmt(&mut self, ctx: &mut Ctx, id: WhileStatementId) -> VisitorResult {
         let while_stmt = &ctx.heap[id];
         let body_id = while_stmt.body;
         let test_expr_id = while_stmt.test;
         self.visit_expr(ctx, test_expr_id)?;
         self.visit_stmt(ctx, body_id)?;
         Ok(())
+    }
     fn visit_synchronous_stmt(&mut self, ctx: &mut Ctx, id: SynchronousStatementId) -> VisitorResult {
         let sync_stmt = &ctx.heap[id];
         let body_id = sync_stmt.body;
         self.visit_stmt(ctx, body_id)
+    }
     fn visit_return_stmt(&mut self, ctx: &mut Ctx, id: ReturnStatementId) -> VisitorResult {
         let return_stmt = &ctx.heap[id];
         let expr_id = return_stmt.expression;
         self.visit_expr(ctx, expr_id)
+    }
     fn visit_assert_stmt(&mut self, ctx: &mut Ctx, id: AssertStatementId) -> VisitorResult {
         let assert_stmt = &ctx.heap[id];
         let test_expr_id = assert_stmt.expression;
         self.visit_expr(ctx, test_expr_id)
+    }
     fn visit_new_stmt(&mut self, ctx: &mut Ctx, id: NewStatementId) -> VisitorResult {
         let new_stmt = &ctx.heap[id];
         let call_expr_id = new_stmt.expression;
         self.visit_call_expr(ctx, call_expr_id)
+    }
     fn visit_put_stmt(&mut self, ctx: &mut Ctx, id: PutStatementId) -> VisitorResult {
         let put_stmt = &ctx.heap[id];
         let port_expr_id = put_stmt.port;
         let msg_expr_id = put_stmt.message;
         // TODO: What what?
         self.visit_expr(ctx, port_expr_id)?;
         self.visit_expr(ctx, msg_expr_id)?;
         Ok(())
+    }
     fn visit_expr_stmt(&mut self, ctx: &mut Ctx, id: ExpressionStatementId) -> VisitorResult {
         let expr_stmt = &ctx.heap[id];
         let subexpr_id = expr_stmt.expression;
         self.visit_expr(ctx, subexpr_id)
+    }
     // Expressions
     fn visit_assignment_expr(&mut self, ctx: &mut Ctx, id: AssignmentExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         self.insert_initial_expr_inference_type(ctx, upcast_id);
+        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
         let assign_expr = &ctx.heap[id];
         let left_expr_id = assign_expr.left;
         let right_expr_id = assign_expr.right;
         self.visit_expr(ctx, left_expr_id)?;
         self.visit_expr(ctx, right_expr_id)?;
         self.progress_assignment_expr(ctx, id)
+    }
     fn visit_conditional_expr(&mut self, ctx: &mut Ctx, id: ConditionalExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         self.insert_initial_expr_inference_type(ctx, upcast_id);
+        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
         let conditional_expr = &ctx.heap[id];
         let test_expr_id = conditional_expr.test;
         let true_expr_id = conditional_expr.true_expression;
         let false_expr_id = conditional_expr.false_expression;
         self.expr_types.insert(test_expr_id, InferenceType::new(false, true, vec![InferenceTypePart::Bool]));
         self.visit_expr(ctx, test_expr_id)?;
         self.visit_expr(ctx, true_expr_id)?;
         self.visit_expr(ctx, false_expr_id)?;
         self.progress_conditional_expr(ctx, id)
+    }
     fn visit_binary_expr(&mut self, ctx: &mut Ctx, id: BinaryExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         self.insert_initial_expr_inference_type(ctx, upcast_id);
+        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
         let binary_expr = &ctx.heap[id];
         let lhs_expr_id = binary_expr.left;
         let rhs_expr_id = binary_expr.right;
         self.visit_expr(ctx, lhs_expr_id)?;
         self.visit_expr(ctx, rhs_expr_id)?;
         self.progress_binary_expr(ctx, id)
+    }
     fn visit_unary_expr(&mut self, ctx: &mut Ctx, id: UnaryExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         self.insert_initial_expr_inference_type(ctx, upcast_id);
+        self.insert_initial_expr_inference_type(ctx, upcast_id)?;
         let unary_expr = &ctx.heap[id];
         let arg_expr_id = unary_expr.expression;
         self.visit_expr(ctx, arg_expr_id);
         self.progress_unary_expr(ctx, id)
+    }
     fn visit_call_expr(&mut self, ctx: &mut Ctx, id: CallExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         self.insert_initial_expr_inference_type(ctx, upcast_id);
         self.insert_initial_expr_inference_type(ctx, upcast_id)?;
         self.insert_initial_call_polymorph_data(ctx, id);
         let call_expr = &ctx.heap[id];
         // TODO: @performance
         let call_expr = &ctx.heap[id];
         for arg_expr_id in call_expr.arguments.clone() {
             self.visit_expr(ctx, arg_expr_id)?;
+        }
         self.progress_call_expr(ctx, id)
+    }
+}
 // TODO: @cleanup Decide to use this where appropriate or to make templates for
 //  everything
 enum TypeClass {
     Numeric, // int and float
     Integer, // only ints
     Boolean, // only boolean
+}
 impl std::fmt::Display for TypeClass {
     fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
         write!(f, "{}", match self {
             TypeClass::Numeric => "numeric",
             TypeClass::Integer => "integer",
             TypeClass::Boolean => "boolean",
         })
+    }
+}
 macro_rules! debug_assert_expr_ids_unique_and_known {
     // Base case for a single expression ID
     ($resolver:ident, $id:ident) => {
         if cfg!(debug_assertions) {
             $resolver.expr_types.contains_key(&$id);
+        }
     };
     // Base case for two expression IDs
     ($resolver:ident, $id1:ident, $id2:ident) => {
         debug_assert_ne!($id1, $id2);
         debug_assert_expr_ids_unique_and_known!($resolver, $id1);
         debug_assert_expr_ids_unique_and_known!($resolver, $id2);
     };
     // Generic case
     ($resolver:ident, $id1:ident, $id2:ident, $($tail:ident),+) => {
         debug_assert_ne!($id1, $id2);
         debug_assert_expr_ids_unique_and_known!($resolver, $id1);
         debug_assert_expr_ids_unique_and_known!($resolver, $id2, $($tail),+);
     };
+}
 enum TypeConstraintResult {
     Progress, // Success: Made progress in applying constraints
     NoProgess, // Success: But did not make any progress in applying constraints
     ErrExprType, // Error: Expression type did not match the argument(s) of the expression type
     ErrArgType, // Error: Expression argument types did not match
+}
 impl TypeResolvingVisitor {
     fn progress_assignment_expr(&mut self, ctx: &mut Ctx, id: AssignmentExpressionId) -> Result<(), ParseError2> {
         use AssignmentOperator as AO;
         // TODO: Assignable check
-        let (type_class, arg1_expr_id, arg2_expr_id) = {
+        let upcast_id = id.upcast();
         let expr = &ctx.heap[id];
             let type_class = match expr.operation {
         let arg1_expr_id = expr.left;
         let arg2_expr_id = expr.right;
         let progress_base = match expr.operation {
             AO::Set =>
-                    None,
+                false,
             AO::Multiplied | AO::Divided | AO::Added | AO::Subtracted =>
-                    Some(TypeClass::Numeric),
+                self.apply_forced_constraint(ctx, upcast_id, &NUMBERLIKE_TEMPLATE)?,
             AO::Remained | AO::ShiftedLeft | AO::ShiftedRight |
             AO::BitwiseAnded | AO::BitwiseXored | AO::BitwiseOred =>
-                    Some(TypeClass::Integer),
+                self.apply_forced_constraint(ctx, upcast_id, &INTEGERLIKE_TEMPLATE)?,
         };
             (type_class, expr.left, expr.right)
         };
         let upcast_id = id.upcast();
         let (progress_expr, progress_arg1, progress_arg2) = self.apply_equal3_constraint(
             ctx, upcast_id, arg1_expr_id, arg2_expr_id
+            ctx, upcast_id, arg1_expr_id, arg2_expr_id, 0
         )?;
         if let Some(type_class) = type_class {
             self.expr_type_is_of_type_class(ctx, id.upcast(), type_class)?
+        }
         if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
         if progress_base || progress_expr { self.queue_expr_parent(ctx, upcast_id); }
         if progress_arg1 { self.queue_expr(arg1_expr_id); }
         if progress_arg2 { self.queue_expr(arg2_expr_id); }
         Ok(())
+    }
     fn progress_conditional_expr(&mut self, ctx: &mut Ctx, id: ConditionalExpressionId) -> Result<(), ParseError2> {
         // Note: test expression type is already enforced
         let upcast_id = id.upcast();
         let expr = &ctx.heap[id];
         let arg1_expr_id = expr.true_expression;
         let arg2_expr_id = expr.false_expression;
         let (progress_expr, progress_arg1, progress_arg2) = self.apply_equal3_constraint(
             ctx, upcast_id, arg1_expr_id, arg2_expr_id
+            ctx, upcast_id, arg1_expr_id, arg2_expr_id, 0
         )?;
         if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
         if progress_arg1 { self.queue_expr(arg1_expr_id); }
         if progress_arg2 { self.queue_expr(arg2_expr_id); }
         Ok(())
+    }
     fn progress_binary_expr(&mut self, ctx: &mut Ctx, id: BinaryExpressionId) -> Result<(), ParseError2> {
         // Note: our expression type might be fixed by our parent, but we still
         // need to make sure it matches the type associated with our operation.
         use BinaryOperator as BO;
         let upcast_id = id.upcast();
         let expr = &ctx.heap[id];
         let arg1_id = expr.left;
         let arg2_id = expr.right;
         let (progress_expr, progress_arg1, progress_arg2) = match expr.operation {
             BO::Concatenate => {
                 // Arguments may be arrays/slices with the same subtype. Output
                 // is always an array with that subtype
                 (false, false, false)
                 // Arguments may be arrays/slices, output is always an array
                 let progress_expr = self.apply_forced_constraint(ctx, upcast_id, &ARRAY_TEMPLATE)?;
                 let progress_arg1 = self.apply_forced_constraint(ctx, arg1_id, &ARRAYLIKE_TEMPLATE)?;
                 let progress_arg2 = self.apply_forced_constraint(ctx, arg2_id, &ARRAYLIKE_TEMPLATE)?;
                 // If they're all arraylike, then we want the subtype to match
                 let (subtype_expr, subtype_arg1, subtype_arg2) =
                     self.apply_equal3_constraint(ctx, upcast_id, arg1_id, arg2_id, 1)?;
                 (progress_expr || subtype_expr, progress_arg1 || subtype_arg1, progress_arg2 || subtype_arg2)
             },
             BO::LogicalOr | BO::LogicalAnd => {
                 // Forced boolean on all
-                let progress_expr = self.apply_forced_constraint(ctx, upcast_id, BOOL_TEMPLATE.as_slice())?;
+                let progress_expr = self.apply_forced_constraint(ctx, upcast_id, &BOOL_TEMPLATE)?;
                 let progress_arg1 = self.apply_forced_constraint(ctx, arg1_id, &BOOL_TEMPLATE)?;
                 let progress_arg2 = self.apply_forced_constraint(ctx, arg2_id, &BOOL_TEMPLATE)?;
                 (progress_expr, progress_arg1, progress_arg2)
             },
             BO::BitwiseOr | BO::BitwiseXor | BO::BitwiseAnd | BO::Remainder | BO::ShiftLeft | BO::ShiftRight => {
                 let result = self.apply_equal3_constraint(ctx, upcast_id, arg1_id, arg2_id)?;
                 self.expr_type_is_of_type_class(ctx, upcast_id, TypeClass::Integer)?;
                 result
                 // All equal of integer type
                 let progress_base = self.apply_forced_constraint(ctx, upcast_id, &INTEGERLIKE_TEMPLATE)?;
                 let (progress_expr, progress_arg1, progress_arg2) =
                     self.apply_equal3_constraint(ctx, upcast_id, arg1_id, arg2_id, 0)?;
                 (progress_base || progress_expr, progress_base || progress_arg1, progress_base || progress_arg2)
             },
             BO::Equality | BO::Inequality | BO::LessThan | BO::GreaterThan | BO::LessThanEqual | BO::GreaterThanEqual => {
                 // Equal2 on args, forced boolean output
                 let progress_expr = self.apply_forced_constraint(ctx, upcast_id, &BOOL_TEMPLATE)?;
                 let (progress_arg1, progress_arg2) = self.apply_equal2_constraint(ctx, upcast_id, arg1_id, arg2_id)?;
                 self.expr_type_is_of_type_class(ctx, arg1_id, TypeClass::Numeric)?;
                 let progress_arg_base = self.apply_forced_constraint(ctx, arg1_id, &NUMBERLIKE_TEMPLATE)?;
                 let (progress_arg1, progress_arg2) =
                     self.apply_equal2_constraint(ctx, upcast_id, arg1_id, 0, arg2_id, 0)?;
                 (progress_expr, progress_arg1, progress_arg2)
+                (progress_expr, progress_arg_base || progress_arg1, progress_arg_base || progress_arg2)
             },
             BO::Add | BO::Subtract | BO::Multiply | BO::Divide => {
                 let result = self.apply_equal3_constraint(ctx, upcast_id, arg1_id, arg2_id)?;
                 self.expr_type_is_of_type_class(ctx, upcast_id, TypeClass::Numeric)?;
                 result
                 // All equal of number type
                 let progress_base = self.apply_forced_constraint(ctx, upcast_id, &NUMBERLIKE_TEMPLATE)?;
                 let (progress_expr, progress_arg1, progress_arg2) =
                     self.apply_equal3_constraint(ctx, upcast_id, arg1_id, arg2_id, 0)?;
                 (progress_base || progress_expr, progress_base || progress_arg1, progress_base || progress_arg2)
             },
         };
         if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
         if progress_arg1 { self.queue_expr(arg1_id); }
         if progress_arg2 { self.queue_expr(arg2_id); }
         Ok(())
+    }
     fn progress_unary_expr(&mut self, ctx: &mut Ctx, id: UnaryExpressionId) -> Result<(), ParseError2> {
         use UnaryOperation as UO;
         let upcast_id = id.upcast();
         let expr = &ctx.heap[id];
         let arg_id = expr.expression;
         let (progress_expr, progress_arg) = match expr.operation {
             UO::Positive | UO::Negative => {
                 // Equal types of numeric class
                 let progress = self.apply_equal2_constraint(ctx, upcast_id, upcast_id, arg_id)?;
                 self.expr_type_is_of_type_class(ctx, upcast_id, TypeClass::Numeric)?;
                 progress
                 let progress_base = self.apply_forced_constraint(ctx, upcast_id, &NUMBERLIKE_TEMPLATE)?;
                 let (progress_expr, progress_arg) =
                     self.apply_equal2_constraint(ctx, upcast_id, upcast_id, 0, arg_id, 0)?;
                 (progress_base || progress_expr, progress_base || progress_arg)
             },
             UO::BitwiseNot | UO::PreIncrement | UO::PreDecrement | UO::PostIncrement | UO::PostDecrement => {
                 // Equal types of integer class
                 let progress = self.apply_equal2_constraint(ctx, upcast_id, upcast_id, arg_id)?;
                 self.expr_type_is_of_type_class(ctx, upcast_id, TypeClass::Integer)?;
                 progress
                 let progress_base = self.apply_forced_constraint(ctx, upcast_id, &INTEGERLIKE_TEMPLATE)?;
                 let (progress_expr, progress_arg) =
                     self.apply_equal2_constraint(ctx, upcast_id, upcast_id, 0, arg_id, 0)?;
                 (progress_base || progress_expr, progress_base || progress_arg)
             },
             UO::LogicalNot => {
                 // Both booleans
                 let progress_expr = self.apply_forced_constraint(ctx, upcast_id, &BOOL_TEMPLATE)?;
                 let progress_arg = self.apply_forced_constraint(ctx, upcast_id, &BOOL_TEMPLATE)?;
                 (progress_expr, progress_arg)
+            }
         };
         if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
         if progress_arg { self.queue_expr(arg_id); }
         Ok(())
+    }
     fn progress_indexing_expr(&mut self, ctx: &mut Ctx, id: IndexingExpressionId) -> Result<(), ParseError2> {
         // TODO: Indexable check
         let upcast_id = id.upcast();
         let expr = &ctx.heap[id];
         let subject_id = expr.subject;
         let index_id = expr.index;
         let progress_subject = self.apply_forced_constraint(ctx, subject_id, &ARRAYLIKE_TEMPLATE)?;
         // Make sure subject is arraylike and index is integerlike
         let progress_subject_base = self.apply_forced_constraint(ctx, subject_id, &ARRAYLIKE_TEMPLATE)?;
         let progress_index = self.apply_forced_constraint(ctx, index_id, &INTEGERLIKE_TEMPLATE)?;
         // TODO: Finish this
         // Make sure if output is of T then subject is Array<T>
         let (progress_expr, progress_subject) =
             self.apply_equal2_constraint(ctx, upcast_id, upcast_id, 0, subject_id, 1)?;
         if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
         if progress_subject_base || progress_subject { self.queue_expr(subject_id); }
         if progress_index { self.queue_expr(index_id); }
         Ok(())
+    }
     fn progress_call_expr(&mut self, ctx: &mut Ctx, id: CallExpressionId) -> Result<(), ParseError2> {
         let
             upcast_id = id.upcast();
     fn progress_slicing_expr(&mut self, ctx: &mut Ctx, id: SlicingExpressionId) -> Result<(), ParseError2> {
         let upcast_id = id.upcast();
         let expr = &ctx.heap[id];
         let subject_id = expr.subject;
         let from_id = expr.from_index;
         let to_id = expr.to_index;
         // Make sure subject is arraylike and indices are of equal integerlike
         let progress_subject_base = self.apply_forced_constraint(ctx, subject_id, &ARRAYLIKE_TEMPLATE)?;
         let progress_idx_base = self.apply_forced_constraint(ctx, from_id, &INTEGERLIKE_TEMPLATE)?;
         let (progress_from, progress_to) = self.apply_equal2_constraint(ctx, upcast_id, from_id, 0, to_id, 0)?;
         // Make sure if output is of T then subject is Array<T>
         let (progress_expr, progress_subject) =
             self.apply_equal2_constraint(ctx, upcast_id, upcast_id, 0, subject_id, 1)?;
         if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
         if progress_subject_base || progress_subject { self.queue_expr(subject_id); }
         if progress_idx_base || progress_from { self.queue_expr(from_id); }
         if progress_idx_base || progress_to { self.queue_expr(to_id); }
         Ok(())
+    }
     fn progress_call_expr(&mut self, ctx: &mut Ctx, id: CallExpressionId) -> Result<(), ParseError2> {
         let upcast_id = id.upcast();
         let expr = &ctx.heap[id];
         let extra = self.extra_data.get_mut(&upcast_id).unwrap();
         // Check if we can make progress using the arguments and/or return types
         // while keeping track of the polyvars we've extended
         let mut poly_progress = HashSet::new();
         debug_assert_eq!(extra.embedded.len(), expr.arguments.len());
         for (arg_idx, arg_id) in expr.arguments.clone().into_iter().enumerate() {
             let extra_type: *mut _ = &mut extra.embedded[arg_idx];
             let (progress_expr, progress_extra) = self.apply_arglike_equal2_constraint(ctx, arg_id, extra_type)?;
             if progress_expr { self.queue_expr(arg_id); }
             if progress_extra {
                 unsafe {
                     // Try to advance each polymorphic variable
                     debug_assert!((*extra_type).has_marker);
                     let mut marker_iter = unsafe { (*extra_type).marker_iter() };
                     for (marker_idx, section) in marker_iter {
                         let poly_type: *mut _ = &mut extra.poly_vars[marker_idx];
                         match InferenceType::infer_subtree_for_single_type(&mut *poly_type, 0, section, 0) {
                             SingleInferenceResult::Unmodified => {},
                             SingleInferenceResult::Modified => {
                                 poly_progress.insert(marker_idx);
                             },
                             SingleInferenceResult::Incompatible => {
                                 todo!("Decent error message, and how?");
+                            }
+                        }
+                    }
+                }
+            }
+        }
         Ok(())
+    }
     fn queue_expr_parent(&mut self, ctx: &Ctx, expr_id: ExpressionId) {
         if let ExpressionParent::Expression(parent_expr_id, _) = &ctx.heap[expr_id].parent() {
             self.expr_queued.insert(*parent_expr_id);
+        }
+    }
     fn queue_expr(&mut self, expr_id: ExpressionId) {
         self.expr_queued.insert(expr_id);
+    }
     /// Applies a forced type constraint: the type associated with the supplied
     /// expression will be molded into the provided "template". The template may
     /// be fully specified (e.g. a bool) or contain "inference" variables (e.g.
     /// an array of T)
     fn apply_forced_constraint(
         &mut self, ctx: &mut Ctx, expr_id: ExpressionId, template: &[InferenceTypePart]
     ) -> Result<bool, ParseError2> {
         debug_assert_expr_ids_unique_and_known!(self, expr_id);
         let expr_type = self.expr_types.get_mut(&expr_id).unwrap();
         match InferenceType::infer_subtree_for_single_type(expr_type, 0, template, 0) {
             InferenceTemplateResult::Modified => Ok(true),
             InferenceTemplateResult::Unmodified => Ok(false),
             InferenceTemplateResult::Incompatible => Err(
             SingleInferenceResult::Modified => Ok(true),
             SingleInferenceResult::Unmodified => Ok(false),
             SingleInferenceResult::Incompatible => Err(
                 self.construct_template_type_error(ctx, expr_id, template)
+            )
+        }
+    }
     /// Applies a type constraint that expects the two provided types to be
     /// equal. We attempt to make progress in inferring the types. If the call
     /// is successful then the composition of all types are made equal.
     /// The "parent" `expr_id` is provided to construct errors.
     fn apply_equal2_constraint(
         &mut self, ctx: &mut Ctx, expr_id: ExpressionId, arg1_id: ExpressionId, arg2_id: ExpressionId
         &mut self, ctx: &Ctx, expr_id: ExpressionId,
         arg1_id: ExpressionId, arg1_start_idx: usize,
         arg2_id: ExpressionId, arg2_start_idx: usize
     ) -> Result<(bool, bool), ParseError2> {
         debug_assert_expr_ids_unique_and_known!(self, arg1_id, arg2_id);
         let arg1_type: *mut _ = self.expr_types.get_mut(&arg1_id).unwrap();
         let arg2_type: *mut _ = self.expr_types.get_mut(&arg2_id).unwrap();
         let infer_res = unsafe{ InferenceType::infer_subtrees_for_both_types(arg1_type, 0, arg2_type, 0) };
         let infer_res = unsafe{ InferenceType::infer_subtrees_for_both_types(
             arg1_type, arg1_start_idx,
             arg2_type, arg2_start_idx
         ) };
         if infer_res == DualInferenceResult::Incompatible {
             return Err(self.construct_arg_type_error(ctx, expr_id, arg1_id, arg2_id));
+        }
         Ok((infer_res.modified_lhs(), infer_res.modified_rhs()))
+    }
     // TODO: @cleanup Bit of a hack, but borrowing rules are really annoying here. Maybe not pack
     //  `ExtraData` together, but keep as a HashMap with very specific keys? e.g. ReturnType(ExprId)
     fn apply_arglike_equal2_constraint(
         &mut self, ctx: &Ctx, expr_id: ExpressionId,
         direct_type: *mut InferenceType
     ) -> Result<(bool, bool), ParseError2> {
         let expr_type: *mut _ = self.expr_types.get_mut(&expr_id).unwrap();
         let infer_res = unsafe{
             InferenceType::infer_subtrees_for_both_types(expr_type, 0, direct_type, 0)
         };
         if infer_res == DualInferenceResult::Incompatible {
             let expr_type = unsafe{ &*expr_type };
             let direct_type = unsafe{ &*direct_type };
             return Err(ParseError2::new_error(
                 &ctx.module.source, ctx.heap[expr_id].position(),
                 &format!(
                     "Expected type '{}' but got '{}'",
                     direct_type.display_name(ctx.heap), expr_type.display_name(ctx.heap)
+                )
             ));
+        }
         Ok((infer_res.modified_lhs(), infer_res.modified_rhs()))
+    }
     /// Applies a type constraint that expects all three provided types to be
     /// equal. In case we can make progress in inferring the types then we
     /// attempt to do so. If the call is successful then the composition of all
     /// types is made equal.
     fn apply_equal3_constraint(
         &mut self, ctx: &mut Ctx, expr_id: ExpressionId,
         arg1_id: ExpressionId, arg2_id: ExpressionId
         &mut self, ctx: &Ctx, expr_id: ExpressionId,
         arg1_id: ExpressionId, arg2_id: ExpressionId,
         start_idx: usize
     ) -> Result<(bool, bool, bool), ParseError2> {
         // Safety: all expression IDs are always distinct, and we do not modify
         //  the container
         debug_assert_expr_ids_unique_and_known!(self, expr_id, arg1_id, arg2_id);
         let expr_type: *mut _ = self.expr_types.get_mut(&expr_id).unwrap();
         let arg1_type: *mut _ = self.expr_types.get_mut(&arg1_id).unwrap();
         let arg2_type: *mut _ = self.expr_types.get_mut(&arg2_id).unwrap();
         let expr_res = unsafe{ InferenceType::infer_subtrees_for_both_types(expr_type, 0, arg1_type, 0) };
         let expr_res = unsafe{
             InferenceType::infer_subtrees_for_both_types(expr_type, start_idx, arg1_type, start_idx)
         };
         if expr_res == DualInferenceResult::Incompatible {
             return Err(self.construct_expr_type_error(ctx, expr_id, arg1_id));
+        }
         let args_res = unsafe{ InferenceType::infer_subtrees_for_both_types(arg1_type, 0, arg2_type, 0) };
         let args_res = unsafe{
             InferenceType::infer_subtrees_for_both_types(arg1_type, start_idx, arg2_type, start_idx) };
         if args_res == DualInferenceResult::Incompatible {
             return Err(self.construct_arg_type_error(ctx, expr_id, arg1_id, arg2_id));
+        }
         // If all types are compatible, but the second call caused the arg1_type
         // to be expanded, then we must also assign this to expr_type.
         let mut progress_expr = expr_res.modified_lhs();
         let mut progress_arg1 = expr_res.modified_rhs();
         let mut progress_arg2 = args_res.modified_rhs();
         if args_res.modified_lhs() {
             unsafe {
                 (*expr_type).parts.clear();
                 (*expr_type).parts.extend((*arg2_type).parts.iter());
                 (*expr_type).parts.drain(start_idx..);
                 (*expr_type).parts.extend_from_slice(&((*arg2_type).parts[start_idx..]));
+            }
             progress_expr = true;
             progress_arg1 = true;
+        }
         Ok((progress_expr, progress_arg1, progress_arg2))
+    }
     /// Applies a typeclass constraint: checks if the type is of a particular
     /// class or not
     fn expr_type_is_of_type_class(
         &mut self, ctx: &mut Ctx, expr_id: ExpressionId, type_class: TypeClass
     ) -> Result<(), ParseError2> {
         debug_assert_expr_ids_unique_and_known!(self, expr_id);
         let expr_type = self.expr_types.get(&expr_id).unwrap();
         let is_ok = match type_class {
             TypeClass::Numeric => expr_type.might_be_numeric(),
             TypeClass::Integer => expr_type.might_be_integer(),
             TypeClass::Boolean => expr_type.might_be_boolean(),
         };
         if is_ok {
             Ok(())
         } else {
             Err(self.construct_type_class_error(ctx, expr_id, type_class))
+        }
+    }
     /// Determines the `InferenceType` for the expression based on the
     /// expression parent. Note that if the parent is another expression, we do
     /// not take special action, instead we let parent expressions fix the type
     /// of subexpressions before they have a chance to call this function.
     /// Hence: if the expression type is already set, this function doesn't do
     /// anything.
     fn insert_initial_expr_inference_type(
         &mut self, ctx: &mut Ctx, expr_id: ExpressionId
     ) {
         // TODO: @cleanup Concept of "parent expression" can be removed, the
         //  type inferer/checker can set this upon the initial pass
     ) -> Result<(), ParseError2> {
         use ExpressionParent as EP;
-        if self.expr_types.contains_key(&expr_id) { return; }
+        use InferenceTypePart as ITP;
         let expr = &ctx.heap[expr_id];
         let inference_type = match expr.parent() {
             EP::None =>
                 // Should have been set by linker
                 unreachable!(),
             EP::Memory(_) | EP::ExpressionStmt(_) | EP::Expression(_, _) =>
                 // Determined during type inference
-                InferenceType::new(false, false, vec![InferredPart::Unknown]),
+                InferenceType::new(false, false, vec![ITP::Unknown]),
             EP::If(_) | EP::While(_) | EP::Assert(_) =>
                 // Must be a boolean
-                InferenceType::new(false, true, vec![InferredPart::Bool]),
+                InferenceType::new(false, true, vec![ITP::Bool]),
             EP::Return(_) =>
                 // Must match the return type of the function
                 if let DefinitionType::Function(func_id) = self.definition_type {
                     let return_parser_type_id = ctx.heap[func_id].return_type;
                     self.determine_inference_type_from_parser_type(ctx, return_parser_type_id)
+                    self.determine_inference_type_from_parser_type(ctx, return_parser_type_id, true)
                 } else {
                     // Cannot happen: definition always set upon body traversal
                     // and "return" calls in components are illegal.
                     unreachable!();
                 },
             EP::New(_) =>
                 // Must be a component call, which we assign a "Void" return
                 // type
-                InferenceType::new(false, true, vec![InferredPart::Void]),
+                InferenceType::new(false, true, vec![ITP::Void]),
             EP::Put(_, 0) =>
                 // TODO: Change put to be a builtin function
                 // port of "put" call
-                InferenceType::new(false, false, vec![InferredPart::Output, InferredPart::Unknown]),
+                InferenceType::new(false, false, vec![ITP::Output, ITP::Unknown]),
             EP::Put(_, 1) =>
                 // TODO: Change put to be a builtin function
                 // message of "put" call
-                InferenceType::new(false, true, vec![InferredPart::Message]),
+                InferenceType::new(false, true, vec![ITP::Message]),
             EP::Put(_, _) =>
                 unreachable!()
         };
         self.expr_types.insert(expr_id, inference_type);
         match self.expr_types.entry(expr_id) {
             Entry::Vacant(vacant) => {
                 vacant.insert(inference_type);
             },
             Entry::Occupied(mut preexisting) => {
                 // We already have an entry, this happens if our parent fixed
                 // our type (e.g. we're used in a conditional expression's test)
                 // but we have a different type.
                 // TODO: Is this ever called? Seems like it can't
                 debug_assert!(false, "I am actually called, my ID is {}", expr_id.index);
                 let old_type = preexisting.get_mut();
                 if let SingleInferenceResult::Incompatible = InferenceType::infer_subtree_for_single_type(
                     old_type, 0, &inference_type.parts, 0
                 ) {
                     return Err(self.construct_expr_type_error(ctx, expr_id, expr_id))
+                }
+            }
+        }
         Ok(())
+    }
     fn insert_initial_call_polymorph_data(
         &mut self, ctx: &mut Ctx, call_id: CallExpressionId
     ) {
         use InferenceTypePart as ITP;
         // Note: the polymorph variables may be partially specified and may
         // contain references to the wrapping definition's (i.e. the proctype
         // we are currently visiting) polymorphic arguments.
         //
         // The arguments of the call may refer to polymorphic variables in the
         // definition of the function we're calling, not of the wrapping
         // definition. We insert markers in these inferred types to be able to
         // map them back and forth to the polymorphic arguments of the function
         // we are calling.
         let call = &ctx.heap[call_id];
         debug_assert!(!call.poly_args.is_empty());
         // Handle the polymorphic variables themselves
         let mut poly_vars = Vec::with_capacity(call.poly_args.len());
         for poly_arg_type_id in call.poly_args.clone() { // TODO: @performance
             poly_vars.push(self.determine_inference_type_from_parser_type(ctx, poly_arg_type_id, true));
+        }
         // Handle the arguments
         // TODO: @cleanup: Maybe factor this out for reuse in the validator/linker, should also
         //  make the code slightly more robust.
         let (embedded_types, return_type) = match &call.method {
             Method::Create => {
                 // Not polymorphic
                 unreachable!("insert initial polymorph data for builtin 'create()' call")
             },
             Method::Fires => {
                 // bool fires<T>(PortLike<T> arg)
+                (
                     vec![InferenceType::new(true, false, vec![ITP::PortLike, ITP::Marker(0), ITP::Unknown])],
                     InferenceType::new(false, true, vec![ITP::Bool])
+                )
             },
             Method::Get => {
                 // T get<T>(input<T> arg)
+                (
                     vec![InferenceType::new(true, false, vec![ITP::Input, ITP::Marker(0), ITP::Unknown])],
                     InferenceType::new(true, false, vec![ITP::Marker(0), ITP::Unknown])
+                )
             },
             Method::Symbolic(symbolic) => {
                 let definition = &ctx.heap[symbolic.definition.unwrap()];
                 match definition {
                     Definition::Component(definition) => {
                         let mut parameter_types = Vec::with_capacity(definition.parameters.len());
                         for param_id in definition.parameters.clone() {
                             let param = &ctx.heap[param_id];
                             let param_parser_type_id = param.parser_type;
                             parameter_types.push(self.determine_inference_type_from_parser_type(ctx, param_parser_type_id, false));
+                        }
                         (parameter_types, InferenceType::new(false, true, vec![InferenceTypePart::Unknown]))
                     },
                     Definition::Function(definition) => {
                         let mut parameter_types = Vec::with_capacity(definition.parameters.len());
                         for param_id in definition.parameters.clone() {
                             let param = &ctx.heap[param_id];
                             let param_parser_type_id = param.parser_type;
                             parameter_types.push(self.determine_inference_type_from_parser_type(ctx, param_parser_type_id, false));
+                        }
                         let return_type = self.determine_inference_type_from_parser_type(ctx, definition.return_type, false);
                         (parameter_types, return_type)
                     },
                     Definition::Struct(_) | Definition::Enum(_) => {
                         unreachable!("insert initial polymorph data for struct/enum");
+                    }
+                }
+            }
         };
         self.extra_data.insert(call_id.upcast(), ExtraData {
             poly_vars,
             embedded: embedded_types,
             returned: return_type
         });
+    }
     /// Determines the initial InferenceType from the provided ParserType. This
     /// may be called with two kinds of intentions:
     /// 1. To resolve a ParserType within the body of a function, or on
     ///     polymorphic arguments to calls/instantiations within that body. This
     ///     means that the polymorphic variables are known and can be replaced
     ///     with the monomorph we're instantiating.
     /// 2. To resolve a ParserType on a called function's definition or on
     ///     an instantiated datatype's members. This means that the polymorphic
     ///     arguments inside those ParserTypes refer to the polymorphic
     ///     variables in the called/instantiated type's definition.
     /// In the second case we place InferenceTypePart::Marker instances such
     /// that we can perform type inference on the polymorphic variables.
     fn determine_inference_type_from_parser_type(
         &mut self, ctx: &mut Ctx, parser_type_id: ParserTypeId
         &mut self, ctx: &Ctx, parser_type_id: ParserTypeId,
         parser_type_in_body: bool
     ) -> InferenceType {
         use ParserTypeVariant as PTV;
-        use InferredPart as IP;
+        use InferenceTypePart as ITP;
         let mut to_consider = VecDeque::with_capacity(16);
         to_consider.push_back(parser_type_id);
         let mut infer_type = Vec::new();
         let mut has_inferred = false;
         let mut has_markers = false;
         while !to_consider.is_empty() {
             let parser_type_id = to_consider.pop_front().unwrap();
             let parser_type = &ctx.heap[parser_type_id];
             match &parser_type.variant {
                 PTV::Message => { infer_type.push(IP::Message); },
                 PTV::Bool => { infer_type.push(IP::Bool); },
                 PTV::Byte => { infer_type.push(IP::Byte); },
                 PTV::Short => { infer_type.push(IP::Short); },
                 PTV::Int => { infer_type.push(IP::Int); },
                 PTV::Long => { infer_type.push(IP::Long); },
                 PTV::String => { infer_type.push(IP::String); },
                 PTV::Message => { infer_type.push(ITP::Message); },
                 PTV::Bool => { infer_type.push(ITP::Bool); },
                 PTV::Byte => { infer_type.push(ITP::Byte); },
                 PTV::Short => { infer_type.push(ITP::Short); },
                 PTV::Int => { infer_type.push(ITP::Int); },
                 PTV::Long => { infer_type.push(ITP::Long); },
                 PTV::String => { infer_type.push(ITP::String); },
                 PTV::IntegerLiteral => { unreachable!("integer literal type on variable type"); },
                 PTV::Inferred => {
-                    infer_type.push(IP::Unknown);
+                    infer_type.push(ITP::Unknown);
                     has_inferred = true;
                 },
                 PTV::Array(subtype_id) => {
-                    infer_type.push(IP::Array);
+                    infer_type.push(ITP::Array);
                     to_consider.push_front(*subtype_id);
                 },
                 PTV::Input(subtype_id) => {
-                    infer_type.push(IP::Input);
+                    infer_type.push(ITP::Input);
                     to_consider.push_front(*subtype_id);
                 },
                 PTV::Output(subtype_id) => {
-                    infer_type.push(IP::Output);
+                    infer_type.push(ITP::Output);
                     to_consider.push_front(*subtype_id);
                 },
                 PTV::Symbolic(symbolic) => {
                     debug_assert!(symbolic.variant.is_some(), "symbolic variant not yet determined");
                     match symbolic.variant.unwrap() {
                         SymbolicParserTypeVariant::PolyArg(_, arg_idx) => {
                             // Retrieve concrete type of argument and add it to
                             // the inference type.
                             debug_assert!(symbolic.poly_args.is_empty()); // TODO: @hkt
                             if parser_type_in_body {
                                 debug_assert!(arg_idx < self.polyvars.len());
                                 for concrete_part in &self.polyvars[arg_idx].v {
                                 infer_type.push(IP::from(*concrete_part));
                                     infer_type.push(ITP::from(*concrete_part));
+                                }
                             } else {
                                 has_markers = true;
                                 infer_type.push(ITP::Marker(arg_idx));
                                 infer_type.push(ITP::Unknown);
+                            }
                         },
                         SymbolicParserTypeVariant::Definition(definition_id) => {
                             // TODO: @cleanup
                             if cfg!(debug_assertions) {
                                 let definition = &ctx.heap[definition_id];
                                 debug_assert!(definition.is_struct() || definition.is_enum()); // TODO: @function_ptrs
                                 let num_poly = match definition {
                                     Definition::Struct(v) => v.poly_vars.len(),
                                     Definition::Enum(v) => v.poly_vars.len(),
                                     _ => unreachable!(),
                                 };
                                 debug_assert_eq!(symbolic.poly_args.len(), num_poly);
+                            }
-                            infer_type.push(IP::Instance(definition_id, symbolic.poly_args.len()));
+                            infer_type.push(ITP::Instance(definition_id, symbolic.poly_args.len()));
                             let mut poly_arg_idx = symbolic.poly_args.len();
                             while poly_arg_idx > 0 {
                                 poly_arg_idx -= 1;
                                 to_consider.push_front(symbolic.poly_args[poly_arg_idx]);
+                            }
+                        }
+                    }
+                }
+            }
+        }
-        InferenceType::new(false, !has_inferred, infer_type)
+        InferenceType::new(has_markers, !has_inferred, infer_type)
+    }
     /// Construct an error when an expression's type does not match. This
     /// happens if we infer the expression type from its arguments (e.g. the
     /// expression type of an addition operator is the type of the arguments)
     /// But the expression type was already set due to our parent (e.g. an
     /// "if statement" or a "logical not" always expecting a boolean)
     fn construct_expr_type_error(
         &self, ctx: &Ctx, expr_id: ExpressionId, arg_id: ExpressionId
     ) -> ParseError2 {
         // TODO: Expand and provide more meaningful information for humans
         let expr = &ctx.heap[expr_id];
         let arg_expr = &ctx.heap[arg_id];
         let expr_type = self.expr_types.get(&expr_id).unwrap();
         let arg_type = self.expr_types.get(&arg_id).unwrap();
         return ParseError2::new_error(
             &ctx.module.source, expr.position(),
             &format!(
                 "Incompatible types: this expression expected a '{}'",
                 expr_type.display_name(&ctx.heap)
+            )
         ).with_postfixed_info(
             &ctx.module.source, arg_expr.position(),
             &format!(
                 "But this expression yields a '{}'",
                 arg_type.display_name(&ctx.heap)
+            )
+        )
+    }
     fn construct_arg_type_error(
         &self, ctx: &Ctx, expr_id: ExpressionId,
         arg1_id: ExpressionId, arg2_id: ExpressionId
     ) -> ParseError2 {
         let expr = &ctx.heap[expr_id];
         let arg1 = &ctx.heap[arg1_id];
         let arg2 = &ctx.heap[arg2_id];
         let arg1_type = self.expr_types.get(&arg1_id).unwrap();
         let arg2_type = self.expr_types.get(&arg2_id).unwrap();
         return ParseError2::new_error(
             &ctx.module.source, expr.position(),
             "Incompatible types: cannot apply this expression"
         ).with_postfixed_info(
             &ctx.module.source, arg1.position(),
             &format!(
                 "Because this expression has type '{}'",
                 arg1_type.display_name(&ctx.heap)
+            )
         ).with_postfixed_info(
             &ctx.module.source, arg2.position(),
             &format!(
                 "But this expression has type '{}'",
                 arg2_type.display_name(&ctx.heap)
+            )
+        )
+    }
     fn construct_type_class_error(
         &self, ctx: &Ctx, expr_id: ExpressionId, type_class: TypeClass
     ) -> ParseError2 {
         let expr = &ctx.heap[expr_id];
         let expr_type = self.expr_types.get(&expr_id).unwrap();
         return ParseError2::new_error(
             &ctx.module.source, expr.position(),
             &format!(
                 "Incompatible types: got a '{}' but expected a {} type",
                 expr_type.display_name(&ctx.heap), type_class
+            )
+        )
+    }
     fn construct_template_type_error(
-        &self, ctx: &Ctx, expr_id: ExpressionId, template: &[InferenceType]
+        &self, ctx: &Ctx, expr_id: ExpressionId, template: &[InferenceTypePart]
     ) -> ParseError2 {
         // TODO: @cleanup
         let fake = InferenceType::new(false, false, Vec::from(template));
         let expr = &ctx.heap[expr_id];
         let expr_type = self.expr_types.get(&expr_id).unwrap();
         return ParseError2::new_error(
             &ctx.module.source, expr.position(),
             &format!(
                 "Incompatible types: got a '{}' but expected a '{}'",
                 expr_type.display_name(&ctx.heap), template.display_name(&ctx.heap)
+            )
+        )
+    }
+}
@@ \ No newline at end of file @@

src/protocol/parser/utils.rs

➞

Show inline comments

 use crate::protocol::ast::*;
 use crate::protocol::inputsource::*;
 use super::symbol_table::*;
 use super::type_table::*;
 /// Utility result type.
 pub(crate) enum FindTypeResult<'t, 'i> {
     // Found the type exactly
     Found(&'t DefinedType),
     // Could not match symbol
     SymbolNotFound{ident_pos: InputPosition},
     // Matched part of the namespaced identifier, but not completely
     SymbolPartial{ident_pos: InputPosition, symbol_pos: InputPosition, ident_iter: NamespacedIdentifierIter<'i>},
     // Symbol matched, but points to a namespace/module instead of a type
     SymbolNamespace{ident_pos: InputPosition, symbol_pos: InputPosition},
+}
 // TODO: @cleanup Find other uses of this pattern
 impl<'t, 'i> FindTypeResult<'t, 'i> {
     /// Utility function to transform the `FindTypeResult` into a `Result` where
     /// `Ok` contains the resolved type, and `Err` contains a `ParseError` which
     /// can be readily returned. This is the most common use.
     pub(crate) fn as_parse_error(self, module_source: &InputSource) -> Result<&'t DefinedType, ParseError2> {
         match self {
             FindTypeResult::Found(defined_type) => Ok(defined_type),
             FindTypeResult::SymbolNotFound{ident_pos} => {
                 Err(ParseError2::new_error(
                     module_source, ident_pos,
                     "Could not resolve this identifier to a symbol"
                 ))
             },
             FindTypeResult::SymbolPartial{ident_pos, symbol_pos, ident_iter} => {
                 Err(ParseError2::new_error(
                     module_source, ident_pos,
                     "Could not fully resolve this identifier to a symbol"
                 ).with_postfixed_info(
                     module_source, symbol_pos,
                     &format!(
                         "The partial identifier '{}' was matched to this symbol",
                         String::from_utf8_lossy(ident_iter.returned_section()),
+                    )
                 ))
             },
             FindTypeResult::SymbolNamespace{ident_pos, symbol_pos} => {
                 Err(ParseError2::new_error(
                     module_source, ident_pos,
                     "This identifier was resolved to a namespace instead of a type"
                 ).with_postfixed_info(
                     module_source, symbol_pos,
                     "This is the referenced namespace"
                 ))
+            }
+        }
+    }
+}
 /// Attempt to find the type pointer to by a (root, identifier) combination. The
 /// type must match exactly (no parts in the namespace iterator remaining) and
 /// must be a type, not a namespace.
 pub(crate) fn find_type_definition<'t, 'i>(
     symbols: &SymbolTable, types: &'t TypeTable,
     root_id: RootId, identifier: &'i NamespacedIdentifier
 ) -> FindTypeResult<'t, 'i> {
     // Lookup symbol
     let symbol = symbols.resolve_namespaced_symbol(root_id, identifier);
     if symbol.is_none() {
         return FindTypeResult::SymbolNotFound{ident_pos: identifier.position};
+    }
     // Make sure we resolved it exactly
     let (symbol, ident_iter) = symbol.unwrap();
     if ident_iter.num_remaining() != 0 {
         return FindTypeResult::SymbolPartial{
             ident_pos: identifier.position,
             symbol_pos: symbol.position,
             ident_iter
         };
+    }
     match symbol.symbol {
         Symbol::Namespace(_) => {
             FindTypeResult::SymbolNamespace{
                 ident_pos: identifier.position,
                 symbol_pos: symbol.position
+            }
         },
         Symbol::Definition((_, definition_id)) => {
             // If this function is called correctly, then we should always be
             // able to match the definition's ID to an entry in the type table.
             let definition = types.get_base_definition(&definition_id);
             debug_assert!(definition.is_some());
             FindTypeResult::Found(definition.unwrap())
+        }
+    }
+}
@@ \ No newline at end of file @@

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

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