CSY/reowolf Changeset - 339b493050e2 · Centrum Wiskunde & Informatica (CWI)

Changeset - 339b493050e2

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0 9 0

MH - 3 years ago 2022-05-14 21:18:24
contact@maxhenger.nl

WIP on tcp listener/socket test

9 files changed with 202 insertions and 50 deletions:

src/protocol/ast.rs

src/protocol/eval/executor.rs

src/protocol/mod.rs

src/protocol/parser/pass_definitions.rs

src/protocol/parser/pass_validation_linking.rs

src/runtime2/component/component.rs

src/runtime2/component/component_internet.rs

src/runtime2/tests/internet.rs

104

std/std.internet.pdl

0 comments (0 inline, 0 general)

src/protocol/ast.rs

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@@ @@ -321,1668 +321,1670 @@ impl Import { @@
 pub struct ImportModule {
     pub this: ImportId,
     // Phase 1: parser
     pub span: InputSpan,
     pub module: Identifier,
     pub alias: Identifier,
     pub module_id: RootId,
+}
 #[derive(Debug, Clone)]
 pub struct AliasedSymbol {
     pub name: Identifier,
     pub alias: Option<Identifier>,
     pub definition_id: DefinitionId,
+}
 #[derive(Debug, Clone)]
 pub struct ImportSymbols {
     pub this: ImportId,
     // Phase 1: parser
     pub span: InputSpan,
     pub module: Identifier,
     pub module_id: RootId,
     pub symbols: Vec<AliasedSymbol>,
+}
 #[derive(Debug, Clone)]
 pub struct Identifier {
     pub span: InputSpan,
     pub value: StringRef<'static>,
+}
 impl Identifier {
     pub(crate) const fn new_empty(span: InputSpan) -> Identifier {
         return Identifier{
             span,
             value: StringRef::new_empty(),
         };
+    }
+}
 impl PartialEq for Identifier {
     fn eq(&self, other: &Self) -> bool {
         return self.value == other.value
+    }
+}
 impl Display for Identifier {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         write!(f, "{}", self.value.as_str())
+    }
+}
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub enum ParserTypeVariant {
     // Special builtin, only usable by the compiler and not constructable by the
     // programmer
     Void,
     InputOrOutput,
     ArrayLike,
     IntegerLike,
     // Basic builtin
     Message,
     Bool,
     UInt8, UInt16, UInt32, UInt64,
     SInt8, SInt16, SInt32, SInt64,
     Character, String,
     // Literals (need to get concrete builtin type during typechecking)
     IntegerLiteral,
     // Marker for inference
     Inferred,
     // Builtins expecting one subsequent type
     Array,
     Input,
     Output,
     // Tuple: expecting any number of elements. Note that the parser type can
     // have one-valued tuples, these will be filtered out later during type
     // checking.
     Tuple(u32), // u32 = number of subsequent types
     // User-defined types
     PolymorphicArgument(DefinitionId, u32), // u32 = index into polymorphic variables
     Definition(DefinitionId, u32), // u32 = number of subsequent types in the type tree.
+}
 impl ParserTypeVariant {
     pub(crate) fn num_embedded(&self) -> usize {
         use ParserTypeVariant::*;
         match self {
             Void | IntegerLike |
             Message | Bool |
             UInt8 | UInt16 | UInt32 | UInt64 |
             SInt8 | SInt16 | SInt32 | SInt64 |
             Character | String | IntegerLiteral |
             Inferred | PolymorphicArgument(_, _) =>
 ,
             ArrayLike | InputOrOutput | Array | Input | Output =>
 ,
             Definition(_, num) | Tuple(num) => *num as usize,
+        }
+    }
+}
 /// ParserTypeElement is an element of the type tree. An element may be
 /// implicit, meaning that the user didn't specify the type, but it was set by
 /// the compiler.
 #[derive(Debug, Clone)]
 pub struct ParserTypeElement {
     pub element_span: InputSpan, // span of this element, not including the child types
     pub variant: ParserTypeVariant,
+}
 /// 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).
 ///
 /// Its contents are the depth-first serialization of the type tree. Each node
 /// is a type that may accept polymorphic arguments. The polymorphic arguments
 /// are then the children of the node.
 #[derive(Debug, Clone)]
 pub struct ParserType {
     pub elements: Vec<ParserTypeElement>,
     pub full_span: InputSpan,
+}
 impl ParserType {
     pub(crate) fn iter_embedded(&self, parent_idx: usize) -> ParserTypeIter {
         ParserTypeIter::new(&self.elements, parent_idx)
+    }
+}
 /// Iterator over the embedded elements of a specific element.
 pub struct ParserTypeIter<'a> {
     pub elements: &'a [ParserTypeElement],
     pub cur_embedded_idx: usize,
+}
 impl<'a> ParserTypeIter<'a> {
     fn new(elements: &'a [ParserTypeElement], parent_idx: usize) -> Self {
         debug_assert!(parent_idx < elements.len(), "parent index exceeds number of elements in ParserType");
         if elements[0].variant.num_embedded() == 0 {
             // Parent element does not have any embedded types, place
             // `cur_embedded_idx` at end so we will always return `None`
             Self{ elements, cur_embedded_idx: elements.len() }
         } else {
             // Parent element has an embedded type
             Self{ elements, cur_embedded_idx: parent_idx + 1 }
+        }
+    }
+}
 impl<'a> Iterator for ParserTypeIter<'a> {
     type Item = &'a [ParserTypeElement];
     fn next(&mut self) -> Option<Self::Item> {
         let elements_len = self.elements.len();
         if self.cur_embedded_idx >= elements_len {
             return None;
+        }
         // Seek to the end of the subtree
         let mut depth = 1;
         let start_element = self.cur_embedded_idx;
         while self.cur_embedded_idx < elements_len {
             let cur_element = &self.elements[self.cur_embedded_idx];
             let depth_change = cur_element.variant.num_embedded() as i32 - 1;
             depth += depth_change;
             debug_assert!(depth >= 0, "illegally constructed ParserType: {:?}", self.elements);
             self.cur_embedded_idx += 1;
             if depth == 0 {
                 break;
+            }
+        }
         debug_assert!(depth == 0, "illegally constructed ParserType: {:?}", self.elements);
         return Some(&self.elements[start_element..self.cur_embedded_idx]);
+    }
+}
 /// ConcreteType is the representation of a type after the type inference and
 /// checker is finished. These are fully typed.
 #[derive(Debug, Clone, Copy, Eq, PartialEq, Hash)]
 pub enum ConcreteTypePart {
     // Special types (cannot be explicitly constructed by the programmer)
     Void,
     // Builtin types without nested types
     Message,
     Bool,
     UInt8, UInt16, UInt32, UInt64,
     SInt8, SInt16, SInt32, SInt64,
     Character, String,
     // Builtin types with one nested type
     Array,
     Slice,
     Input,
     Output,
     Pointer,
     // Tuple: variable number of nested types, will never be 1
     Tuple(u32),
     // User defined type with any number of nested types
     Instance(DefinitionId, u32),    // instance of data type
     Function(ProcedureDefinitionId, u32),    // instance of function
     Component(ProcedureDefinitionId, u32),   // instance of a connector
+}
 impl ConcreteTypePart {
     pub(crate) fn num_embedded(&self) -> u32 {
         use ConcreteTypePart::*;
         match self {
             Void | Message | Bool |
             UInt8 | UInt16 | UInt32 | UInt64 |
             SInt8 | SInt16 | SInt32 | SInt64 |
             Character | String =>
 ,
             Array | Slice | Input | Output | Pointer =>
 ,
             Tuple(num_embedded) => *num_embedded,
             Instance(_, num_embedded) => *num_embedded,
             Function(_, num_embedded) => *num_embedded,
             Component(_, num_embedded) => *num_embedded,
+        }
+    }
+}
 #[derive(Debug, Clone, Eq, PartialEq)]
 pub struct ConcreteType {
     pub(crate) parts: Vec<ConcreteTypePart>
+}
 impl Default for ConcreteType {
     fn default() -> Self {
         Self{ parts: Vec::new() }
+    }
+}
 impl ConcreteType {
     /// Returns an iterator over the subtrees that are type arguments (e.g. an
     /// array element's type, or a polymorphic type's arguments) to the
     /// provided parent type (specified by its index in the `parts` array).
     pub(crate) fn embedded_iter(&self, parent_part_idx: usize) -> ConcreteTypeIter {
         return ConcreteTypeIter::new(&self.parts, parent_part_idx);
+    }
     /// Construct a human-readable name for the type. Because this performs
     /// a string allocation don't use it for anything else then displaying the
     /// type to the user.
     pub(crate) fn display_name(&self, heap: &Heap) -> String {
         return Self::type_parts_display_name(self.parts.as_slice(), heap);
+    }
     // --- Utilities that operate on slice of parts
     /// Given the starting position of a type tree, determine the exclusive
     /// ending index.
     pub(crate) fn type_parts_subtree_end_idx(parts: &[ConcreteTypePart], start_idx: usize) -> usize {
         let mut depth = 1;
         let num_parts = parts.len();
         debug_assert!(start_idx < num_parts);
         for part_idx in start_idx..parts.len() {
             let depth_change = parts[part_idx].num_embedded() as i32 - 1;
             depth += depth_change;
             debug_assert!(depth >= 0);
             if depth == 0 {
                 return part_idx + 1;
+            }
+        }
         debug_assert!(false, "incorrectly constructed ConcreteType instance");
         return 0;
+    }
     /// Produces a human-readable representation of the concrete type parts
     fn type_parts_display_name(parts: &[ConcreteTypePart], heap: &Heap) -> String {
         let mut name = String::with_capacity(128);
         let _final_idx = Self::render_type_part_at(parts, heap, 0, &mut name);
         debug_assert_eq!(_final_idx, parts.len());
         return name;
+    }
     /// Produces a human-readable representation of a single type part. Lower
     /// level utility for `type_parts_display_name`.
     fn render_type_part_at(parts: &[ConcreteTypePart], heap: &Heap, mut idx: usize, target: &mut String) -> usize {
         use ConcreteTypePart as CTP;
         use crate::protocol::parser::token_parsing::*;
         let cur_idx = idx;
         idx += 1; // increment by 1, because it always happens
         match parts[cur_idx] {
             CTP::Void => { target.push_str("void"); },
             CTP::Message => { target.push_str(KW_TYPE_MESSAGE_STR); },
             CTP::Bool => { target.push_str(KW_TYPE_BOOL_STR); },
             CTP::UInt8 => { target.push_str(KW_TYPE_UINT8_STR); },
             CTP::UInt16 => { target.push_str(KW_TYPE_UINT16_STR); },
             CTP::UInt32 => { target.push_str(KW_TYPE_UINT32_STR); },
             CTP::UInt64 => { target.push_str(KW_TYPE_UINT64_STR); },
             CTP::SInt8 => { target.push_str(KW_TYPE_SINT8_STR); },
             CTP::SInt16 => { target.push_str(KW_TYPE_SINT16_STR); },
             CTP::SInt32 => { target.push_str(KW_TYPE_SINT32_STR); },
             CTP::SInt64 => { target.push_str(KW_TYPE_SINT64_STR); },
             CTP::Character => { target.push_str(KW_TYPE_CHAR_STR); },
             CTP::String => { target.push_str(KW_TYPE_STRING_STR); },
             CTP::Array | CTP::Slice => {
                 idx = Self::render_type_part_at(parts, heap, idx, target);
                 target.push_str("[]");
             },
             CTP::Input => {
                 target.push_str(KW_TYPE_IN_PORT_STR);
                 target.push('<');
                 idx = Self::render_type_part_at(parts, heap, idx, target);
                 target.push('>');
             },
             CTP::Output => {
                 target.push_str(KW_TYPE_OUT_PORT_STR);
                 target.push('<');
                 idx = Self::render_type_part_at(parts, heap, idx, target);
                 target.push('>');
             },
             CTP::Pointer => {
                 target.push('*');
                 idx = Self::render_type_part_at(parts, heap, idx, target);
+            }
             CTP::Tuple(num_parts) => {
                 target.push('(');
                 if num_parts != 0 {
                     idx = Self::render_type_part_at(parts, heap, idx, target);
                     for _ in 1..num_parts {
                         target.push(',');
                         idx = Self::render_type_part_at(parts, heap, idx, target);
+                    }
+                }
                 target.push(')');
             },
             CTP::Instance(definition_id, num_poly_args) => {
                 idx = Self::render_definition_type_parts_at(parts, heap, definition_id, num_poly_args, idx, target);
+            }
             CTP::Function(definition_id, num_poly_args) |
             CTP::Component(definition_id, num_poly_args) => {
                 idx = Self::render_definition_type_parts_at(parts, heap, definition_id.upcast(), num_poly_args, idx, target);
+            }
+        }
         idx
+    }
     fn render_definition_type_parts_at(parts: &[ConcreteTypePart], heap: &Heap, definition_id: DefinitionId, num_poly_args: u32, mut idx: usize, target: &mut String) -> usize {
         let definition = &heap[definition_id];
         target.push_str(definition.identifier().value.as_str());
         if num_poly_args != 0 {
             target.push('<');
             for poly_arg_idx in 0..num_poly_args {
                 if poly_arg_idx != 0 {
                     target.push(',');
+                }
                 idx = Self::render_type_part_at(parts, heap, idx, target);
+            }
             target.push('>');
+        }
         return idx;
+    }
+}
 #[derive(Debug)]
 pub struct ConcreteTypeIter<'a> {
     parts: &'a [ConcreteTypePart],
     idx_embedded: u32,
     num_embedded: u32,
     part_idx: usize,
+}
 impl<'a> ConcreteTypeIter<'a> {
     pub(crate) fn new(parts: &'a[ConcreteTypePart], parent_idx: usize) -> Self {
         let num_embedded = parts[parent_idx].num_embedded();
         return ConcreteTypeIter{
             parts,
             idx_embedded: 0,
             num_embedded,
             part_idx: parent_idx + 1,
+        }
+    }
+}
 impl<'a> Iterator for ConcreteTypeIter<'a> {
     type Item = &'a [ConcreteTypePart];
     fn next(&mut self) -> Option<Self::Item> {
         if self.idx_embedded == self.num_embedded {
             return None;
+        }
         // Retrieve the subtree of interest
         let start_idx = self.part_idx;
         let end_idx = ConcreteType::type_parts_subtree_end_idx(&self.parts, start_idx);
         self.idx_embedded += 1;
         self.part_idx = end_idx;
         return Some(&self.parts[start_idx..end_idx]);
+    }
+}
 #[derive(Debug, Clone, Copy)]
 pub enum ScopeAssociation {
     Definition(DefinitionId),
     Block(BlockStatementId),
     If(IfStatementId, bool), // if true, then body of "if", otherwise body of "else"
     While(WhileStatementId),
     Synchronous(SynchronousStatementId),
     SelectCase(SelectStatementId, u32), // index is select case
+}
 /// `ScopeNode` is a helper that links scopes in two directions. It doesn't
 /// actually contain any information associated with the scope, this may be
 /// found on the AST elements that `Scope` points to.
 #[derive(Debug, Clone)]
 pub struct Scope {
     // Relation to other scopes
     pub this: ScopeId,
     pub parent: Option<ScopeId>,
     pub nested: Vec<ScopeId>,
     // Locally available variables/labels
     pub association: ScopeAssociation,
     pub variables: Vec<VariableId>,
     pub labels: Vec<LabeledStatementId>,
     // Location trackers/counters
     pub relative_pos_in_parent: i32,
     pub first_unique_id_in_scope: i32,
     pub next_unique_id_in_scope: i32,
+}
 impl Scope {
     pub(crate) fn new(id: ScopeId, association: ScopeAssociation) -> Self {
         return Self{
             this: id,
             parent: None,
             nested: Vec::new(),
             association,
             variables: Vec::new(),
             labels: Vec::new(),
             relative_pos_in_parent: -1,
             first_unique_id_in_scope: -1,
             next_unique_id_in_scope: -1,
+        }
+    }
+}
 impl Scope {
     pub(crate) fn new_invalid(this: ScopeId) -> Self {
         return Self{
             this,
             parent: None,
             nested: Vec::new(),
             association: ScopeAssociation::Definition(DefinitionId::new_invalid()),
             variables: Vec::new(),
             labels: Vec::new(),
             relative_pos_in_parent: -1,
             first_unique_id_in_scope: -1,
             next_unique_id_in_scope: -1,
         };
+    }
+}
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub enum VariableKind {
     Parameter,      // in parameter list of function/component
     Local,          // declared in function/component body
     Binding,        // may be bound to in a binding expression (determined in validator/linker)
+}
 #[derive(Debug, Clone)]
 pub struct Variable {
     pub this: VariableId,
     // Parsing
     pub kind: VariableKind,
     pub parser_type: ParserType,
     pub identifier: Identifier,
     // Validator/linker
     pub relative_pos_in_parent: i32,
     pub unique_id_in_scope: i32, // Temporary fix until proper bytecode/asm is generated
+}
 #[derive(Debug)]
 pub enum Definition {
     Struct(StructDefinition),
     Enum(EnumDefinition),
     Union(UnionDefinition),
     Procedure(ProcedureDefinition),
+}
 impl Definition {
     pub fn is_struct(&self) -> bool {
         match self {
             Definition::Struct(_) => true,
             _ => false
+        }
+    }
     pub(crate) fn as_struct(&self) -> &StructDefinition {
         match self {
             Definition::Struct(result) => result,
             _ => panic!("Unable to cast 'Definition' to 'StructDefinition'"),
+        }
+    }
     pub(crate) fn as_struct_mut(&mut self) -> &mut 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(crate) fn as_enum(&self) -> &EnumDefinition {
         match self {
             Definition::Enum(result) => result,
             _ => panic!("Unable to cast 'Definition' to 'EnumDefinition'"),
+        }
+    }
     pub(crate) fn as_enum_mut(&mut self) -> &mut EnumDefinition {
         match self {
             Definition::Enum(result) => result,
             _ => panic!("Unable to cast 'Definition' to 'EnumDefinition'"),
+        }
+    }
     pub fn is_union(&self) -> bool {
         match self {
             Definition::Union(_) => true,
             _ => false,
+        }
+    }
     pub(crate) fn as_union(&self) -> &UnionDefinition {
         match self {
             Definition::Union(result) => result,
             _ => panic!("Unable to cast 'Definition' to 'UnionDefinition'"),
+        }
+    }
     pub(crate) fn as_union_mut(&mut self) -> &mut UnionDefinition {
         match self {
             Definition::Union(result) => result,
             _ => panic!("Unable to cast 'Definition' to 'UnionDefinition'"),
+        }
+    }
     pub fn is_procedure(&self) -> bool {
         match self {
             Definition::Procedure(_) => true,
             _ => false,
+        }
+    }
     pub(crate) fn as_procedure(&self) -> &ProcedureDefinition {
         match self {
             Definition::Procedure(result) => result,
             _ => panic!("Unable to cast `Definition` to `Function`"),
+        }
+    }
     pub(crate) fn as_procedure_mut(&mut self) -> &mut ProcedureDefinition {
         match self {
             Definition::Procedure(result) => result,
             _ => panic!("Unable to cast `Definition` to `Function`"),
+        }
+    }
     pub fn defined_in(&self) -> RootId {
         match self {
             Definition::Struct(def) => def.defined_in,
             Definition::Enum(def) => def.defined_in,
             Definition::Union(def) => def.defined_in,
             Definition::Procedure(def) => def.defined_in,
+        }
+    }
     pub fn identifier(&self) -> &Identifier {
         match self {
             Definition::Struct(def) => &def.identifier,
             Definition::Enum(def) => &def.identifier,
             Definition::Union(def) => &def.identifier,
             Definition::Procedure(def) => &def.identifier,
+        }
+    }
     pub fn poly_vars(&self) -> &Vec<Identifier> {
         match self {
             Definition::Struct(def) => &def.poly_vars,
             Definition::Enum(def) => &def.poly_vars,
             Definition::Union(def) => &def.poly_vars,
             Definition::Procedure(def) => &def.poly_vars,
+        }
+    }
+}
 #[derive(Debug, Clone)]
 pub struct StructFieldDefinition {
     pub span: InputSpan,
     pub field: Identifier,
     pub parser_type: ParserType,
+}
 #[derive(Debug, Clone)]
 pub struct StructDefinition {
     pub this: StructDefinitionId,
     pub defined_in: RootId,
     // Symbol scanning
     pub identifier: Identifier,
     pub poly_vars: Vec<Identifier>,
     // Parsing
     pub fields: Vec<StructFieldDefinition>
+}
 impl StructDefinition {
     pub(crate) fn new_empty(
         this: StructDefinitionId, defined_in: RootId,
         identifier: Identifier, poly_vars: Vec<Identifier>
     ) -> Self {
         Self{ this, defined_in, identifier, poly_vars, fields: Vec::new() }
+    }
+}
 #[derive(Debug, Clone, Copy)]
 pub enum EnumVariantValue {
     None,
     Integer(i64),
+}
 #[derive(Debug, Clone)]
 pub struct EnumVariantDefinition {
     pub identifier: Identifier,
     pub value: EnumVariantValue,
+}
 #[derive(Debug, Clone)]
 pub struct EnumDefinition {
     pub this: EnumDefinitionId,
     pub defined_in: RootId,
     // Symbol scanning
     pub identifier: Identifier,
     pub poly_vars: Vec<Identifier>,
     // Parsing
     pub variants: Vec<EnumVariantDefinition>,
+}
 impl EnumDefinition {
     pub(crate) fn new_empty(
         this: EnumDefinitionId, defined_in: RootId,
         identifier: Identifier, poly_vars: Vec<Identifier>
     ) -> Self {
         Self{ this, defined_in, identifier, poly_vars, variants: Vec::new() }
+    }
+}
 #[derive(Debug, Clone)]
 pub struct UnionVariantDefinition {
     pub span: InputSpan,
     pub identifier: Identifier,
     pub value: Vec<ParserType>, // if empty, then union variant does not contain any embedded types
+}
 #[derive(Debug, Clone)]
 pub struct UnionDefinition {
     pub this: UnionDefinitionId,
     pub defined_in: RootId,
     // Phase 1: symbol scanning
     pub identifier: Identifier,
     pub poly_vars: Vec<Identifier>,
     // Phase 2: parsing
     pub variants: Vec<UnionVariantDefinition>,
+}
 impl UnionDefinition {
     pub(crate) fn new_empty(
         this: UnionDefinitionId, defined_in: RootId,
         identifier: Identifier, poly_vars: Vec<Identifier>
     ) -> Self {
         Self{ this, defined_in, identifier, poly_vars, variants: Vec::new() }
+    }
+}
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum ProcedureKind {
     Function, // with return type
     Component,
+}
 /// Monomorphed instantiation of a procedure (or the sole instantiation of a
 /// non-polymorphic procedure).
 #[derive(Debug)]
 pub struct ProcedureDefinitionMonomorph {
     pub argument_types: Vec<TypeId>,
     pub expr_info: Vec<ExpressionInfo>
+}
 impl ProcedureDefinitionMonomorph {
     pub(crate) fn new_invalid() -> Self {
         return Self{
             argument_types: Vec::new(),
             expr_info: Vec::new(),
+        }
+    }
+}
 #[derive(Debug, Clone, Copy)]
 pub struct ExpressionInfo {
     pub type_id: TypeId,
     pub variant: ExpressionInfoVariant,
+}
 impl ExpressionInfo {
     pub(crate) fn new_invalid() -> Self {
         return Self{
             type_id: TypeId::new_invalid(),
             variant: ExpressionInfoVariant::Generic,
+        }
+    }
+}
 #[derive(Debug, Clone, Copy)]
 pub enum ExpressionInfoVariant {
     Generic,
     Procedure(TypeId, u32), // procedure TypeID and its monomorph index
     Select(i32), // index
+}
 impl ExpressionInfoVariant {
     pub(crate) fn as_select(&self) -> i32 {
         match self {
             ExpressionInfoVariant::Select(v) => *v,
             _ => unreachable!(),
+        }
+    }
     pub(crate) fn as_procedure(&self) -> (TypeId, u32) {
         match self {
             ExpressionInfoVariant::Procedure(type_id, monomorph_index) => (*type_id, *monomorph_index),
             _ => unreachable!(),
+        }
+    }
+}
 #[derive(Debug)]
 pub enum ProcedureSource {
     FuncUserDefined,
     CompUserDefined,
     // Builtin functions, available to user
     FuncGet,
     FuncPut,
     FuncFires,
     FuncCreate,
     FuncLength,
     FuncAssert,
     FuncPrint,
     // Buitlin functions, not available to user
     FuncSelectStart,
     FuncSelectRegisterCasePort,
     FuncSelectWait,
     // Builtin components, available to user
     CompRandomU32, // TODO: Remove, temporary thing
     CompTcpClient,
     CompTcpListener,
+}
 impl ProcedureSource {
     pub(crate) fn is_builtin(&self) -> bool {
         match self {
             ProcedureSource::FuncUserDefined | ProcedureSource::CompUserDefined => false,
             _ => true,
+        }
+    }
+}
 /// Generic storage for functions and components.
 // Note that we will have function definitions for builtin functions as well. In
 // that case the span, the identifier span and the body are all invalid.
 #[derive(Debug)]
 pub struct ProcedureDefinition {
     pub this: ProcedureDefinitionId,
     pub defined_in: RootId,
     // Symbol scanning
     pub kind: ProcedureKind,
     pub identifier: Identifier,
     pub poly_vars: Vec<Identifier>,
     // Parser
     pub source: ProcedureSource,
     pub return_type: Option<ParserType>, // present on functions, not components
     pub parameters: Vec<VariableId>,
     pub scope: ScopeId,
     pub body: BlockStatementId,
     // Monomorphization of typed procedures
     pub monomorphs: Vec<ProcedureDefinitionMonomorph>,
+}
 impl ProcedureDefinition {
     pub(crate) fn new_empty(
         this: ProcedureDefinitionId, defined_in: RootId,
         kind: ProcedureKind, identifier: Identifier, poly_vars: Vec<Identifier>
     ) -> Self {
         Self {
             this, defined_in,
             kind, identifier, poly_vars,
             source: ProcedureSource::FuncUserDefined,
             return_type: None,
             parameters: Vec::new(),
             scope: ScopeId::new_invalid(),
             body: BlockStatementId::new_invalid(),
             monomorphs: Vec::new(),
+        }
+    }
+}
 #[derive(Debug, Clone)]
 pub enum Statement {
     Block(BlockStatement),
     EndBlock(EndBlockStatement),
     Local(LocalStatement),
     Labeled(LabeledStatement),
     If(IfStatement),
     EndIf(EndIfStatement),
     While(WhileStatement),
     EndWhile(EndWhileStatement),
     Break(BreakStatement),
     Continue(ContinueStatement),
     Synchronous(SynchronousStatement),
     EndSynchronous(EndSynchronousStatement),
     Fork(ForkStatement),
     EndFork(EndForkStatement),
     Select(SelectStatement),
     EndSelect(EndSelectStatement),
     Return(ReturnStatement),
     Goto(GotoStatement),
     New(NewStatement),
     Expression(ExpressionStatement),
+}
 impl Statement {
     pub fn as_new(&self) -> &NewStatement {
         match self {
             Statement::New(result) => result,
             _ => panic!("Unable to cast `Statement` to `NewStatement`"),
+        }
+    }
     pub fn span(&self) -> InputSpan {
         match self {
             Statement::Block(v) => v.span,
             Statement::Local(v) => v.span(),
             Statement::Labeled(v) => v.label.span,
             Statement::If(v) => v.span,
             Statement::While(v) => v.span,
             Statement::Break(v) => v.span,
             Statement::Continue(v) => v.span,
             Statement::Synchronous(v) => v.span,
             Statement::Fork(v) => v.span,
             Statement::Select(v) => v.span,
             Statement::Return(v) => v.span,
             Statement::Goto(v) => v.span,
             Statement::New(v) => v.span,
             Statement::Expression(v) => v.span,
             Statement::EndBlock(_)
             | Statement::EndIf(_)
             | Statement::EndWhile(_)
             | Statement::EndSynchronous(_)
             | Statement::EndFork(_)
             | Statement::EndSelect(_) => unreachable!(),
+        }
+    }
     pub fn link_next(&mut self, next: StatementId) {
         match self {
             Statement::Block(stmt) => stmt.next = next,
             Statement::EndBlock(stmt) => stmt.next = next,
             Statement::Local(stmt) => match stmt {
                 LocalStatement::Channel(stmt) => stmt.next = next,
                 LocalStatement::Memory(stmt) => stmt.next = next,
             },
             Statement::EndIf(stmt) => stmt.next = next,
             Statement::EndWhile(stmt) => stmt.next = next,
             Statement::EndSynchronous(stmt) => stmt.next = next,
             Statement::EndFork(stmt) => stmt.next = next,
             Statement::EndSelect(stmt) => stmt.next = next,
             Statement::New(stmt) => stmt.next = next,
             Statement::Expression(stmt) => stmt.next = next,
             Statement::Return(_)
             | Statement::Break(_)
             | Statement::Continue(_)
             | Statement::Synchronous(_)
             | Statement::Fork(_)
             | Statement::Select(_)
             | Statement::Goto(_)
             | Statement::While(_)
             | Statement::Labeled(_)
             | Statement::If(_) => unreachable!(),
+        }
+    }
+}
 #[derive(Debug, Clone)]
 pub struct BlockStatement {
     pub this: BlockStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the complete block
     pub statements: Vec<StatementId>,
     pub end_block: EndBlockStatementId,
     // Phase 2: linker
     pub scope: ScopeId,
     pub next: StatementId,
+}
 #[derive(Debug, Clone)]
 pub struct EndBlockStatement {
     pub this: EndBlockStatementId,
     // Parser
     pub start_block: BlockStatementId,
     // Validation/Linking
     pub next: StatementId,
+}
 #[derive(Debug, Clone)]
 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 span(&self) -> InputSpan {
         match self {
             LocalStatement::Channel(v) => v.span,
             LocalStatement::Memory(v) => v.span,
+        }
+    }
+}
 #[derive(Debug, Clone)]
 pub struct MemoryStatement {
     pub this: MemoryStatementId,
     // Phase 1: parser
     pub span: InputSpan,
     pub variable: VariableId,
     pub initial_expr: AssignmentExpressionId,
     // Phase 2: linker
     pub next: StatementId,
+}
 /// 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)]
 pub struct ChannelStatement {
     pub this: ChannelStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the "channel" keyword
     pub from: VariableId, // output
     pub to: VariableId,   // input
     // Phase 2: linker
     pub relative_pos_in_parent: i32,
     pub next: StatementId,
+}
 #[derive(Debug, Clone)]
 pub struct LabeledStatement {
     pub this: LabeledStatementId,
     // Phase 1: parser
     pub label: Identifier,
     pub body: StatementId,
     // Phase 2: linker
     pub relative_pos_in_parent: i32,
     pub in_sync: SynchronousStatementId, // may be invalid
+}
 #[derive(Debug, Clone)]
 pub struct IfStatement {
     pub this: IfStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the "if" keyword
     pub test: ExpressionId,
     pub true_case: IfStatementCase,
     pub false_case: Option<IfStatementCase>,
     pub end_if: EndIfStatementId,
+}
 #[derive(Debug, Clone, Copy)]
 pub struct IfStatementCase {
     pub body: StatementId,
     pub scope: ScopeId,
+}
 #[derive(Debug, Clone)]
 pub struct EndIfStatement {
     pub this: EndIfStatementId,
     pub start_if: IfStatementId,
     pub next: StatementId,
+}
 #[derive(Debug, Clone)]
 pub struct WhileStatement {
     pub this: WhileStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the "while" keyword
     pub test: ExpressionId,
     pub scope: ScopeId,
     pub body: StatementId,
     pub end_while: EndWhileStatementId,
     pub in_sync: SynchronousStatementId, // may be invalid
+}
 #[derive(Debug, Clone)]
 pub struct EndWhileStatement {
     pub this: EndWhileStatementId,
     pub start_while: WhileStatementId,
     // Phase 2: linker
     pub next: StatementId,
+}
 #[derive(Debug, Clone)]
 pub struct BreakStatement {
     pub this: BreakStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the "break" keyword
     pub label: Option<Identifier>,
     // Phase 2: linker
     pub target: EndWhileStatementId, // invalid if not yet set
+}
 #[derive(Debug, Clone)]
 pub struct ContinueStatement {
     pub this: ContinueStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the "continue" keyword
     pub label: Option<Identifier>,
     // Phase 2: linker
     pub target: WhileStatementId, // invalid if not yet set
+}
 #[derive(Debug, Clone)]
 pub struct SynchronousStatement {
     pub this: SynchronousStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the "sync" keyword
     pub scope: ScopeId,
     pub body: StatementId,
     pub end_sync: EndSynchronousStatementId,
+}
 #[derive(Debug, Clone)]
 pub struct EndSynchronousStatement {
     pub this: EndSynchronousStatementId,
     pub start_sync: SynchronousStatementId,
     // Phase 2: linker
     pub next: StatementId,
+}
 #[derive(Debug, Clone)]
 pub struct ForkStatement {
     pub this: ForkStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the "fork" keyword
     pub left_body: StatementId,
     pub right_body: Option<StatementId>,
     pub end_fork: EndForkStatementId,
+}
 #[derive(Debug, Clone)]
 pub struct EndForkStatement {
     pub this: EndForkStatementId,
     pub start_fork: ForkStatementId,
     pub next: StatementId,
+}
 #[derive(Debug, Clone)]
 pub struct SelectStatement {
     pub this: SelectStatementId,
     pub span: InputSpan, // of the "select" keyword
     pub cases: Vec<SelectCase>,
     pub end_select: EndSelectStatementId,
     pub relative_pos_in_parent: i32,
     pub next: StatementId, // note: the select statement will be transformed into other AST elements, this `next` jumps to those replacement statements
+}
 #[derive(Debug, Clone)]
 pub struct SelectCase {
     // The guard statement of a `select` is either a MemoryStatement or an
     // ExpressionStatement. Nothing else is allowed by the initial parsing
     pub guard: StatementId,
     pub body: StatementId,
     pub scope: ScopeId,
     // Phase 2: Validation and Linking
     pub involved_ports: Vec<(CallExpressionId, ExpressionId)>, // call to `get` and its port argument
+}
 #[derive(Debug, Clone)]
 pub struct EndSelectStatement {
     pub this: EndSelectStatementId,
     pub start_select: SelectStatementId,
     pub next: StatementId,
+}
 #[derive(Debug, Clone)]
 pub struct ReturnStatement {
     pub this: ReturnStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the "return" keyword
     pub expressions: Vec<ExpressionId>,
+}
 #[derive(Debug, Clone)]
 pub struct GotoStatement {
     pub this: GotoStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the "goto" keyword
     pub label: Identifier,
     // Phase 2: linker
     pub target: LabeledStatementId, // invalid if not yet set
+}
 #[derive(Debug, Clone)]
 pub struct NewStatement {
     pub this: NewStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the "new" keyword
     pub expression: CallExpressionId,
     // Phase 2: linker
     pub next: StatementId,
+}
 #[derive(Debug, Clone)]
 pub struct ExpressionStatement {
     pub this: ExpressionStatementId,
     // Phase 1: parser
     pub span: InputSpan,
     pub expression: ExpressionId,
     // Phase 2: linker
     pub next: StatementId,
+}
 #[derive(Debug, PartialEq, Eq, Clone, Copy)]
 pub enum ExpressionParent {
     None, // only set during initial parsing
     Memory(MemoryStatementId),
     If(IfStatementId),
     While(WhileStatementId),
     Return(ReturnStatementId),
     New(NewStatementId),
     ExpressionStmt(ExpressionStatementId),
     Expression(ExpressionId, u32) // index within expression (e.g LHS or RHS of expression, or index in array literal, etc.)
+}
 impl ExpressionParent {
     pub fn is_new(&self) -> bool {
         match self {
             ExpressionParent::New(_) => true,
             _ => false,
+        }
+    }
     pub fn as_expression(&self) -> ExpressionId {
         match self {
             ExpressionParent::Expression(id, _) => *id,
             _ => panic!("called as_expression() on {:?}", self),
+        }
+    }
+}
 #[derive(Debug, Clone)]
 pub enum Expression {
     Assignment(AssignmentExpression),
     Binding(BindingExpression),
     Conditional(ConditionalExpression),
     Binary(BinaryExpression),
     Unary(UnaryExpression),
     Indexing(IndexingExpression),
     Slicing(SlicingExpression),
     Select(SelectExpression),
     Literal(LiteralExpression),
     Cast(CastExpression),
     Call(CallExpression),
     Variable(VariableExpression),
+}
 impl Expression {
     pub fn as_variable(&self) -> &VariableExpression {
         match self {
             Expression::Variable(result) => result,
             _ => panic!("Unable to cast `Expression` to `VariableExpression`"),
+        }
+    }
     /// Returns operator span, function name, a binding's "let" span, etc. An
     /// indicator for the kind of expression that is being applied.
     pub fn operation_span(&self) -> InputSpan {
         match self {
             Expression::Assignment(expr) => expr.operator_span,
             Expression::Binding(expr) => expr.operator_span,
             Expression::Conditional(expr) => expr.operator_span,
             Expression::Binary(expr) => expr.operator_span,
             Expression::Unary(expr) => expr.operator_span,
             Expression::Indexing(expr) => expr.operator_span,
             Expression::Slicing(expr) => expr.slicing_span,
             Expression::Select(expr) => expr.operator_span,
             Expression::Literal(expr) => expr.span,
             Expression::Cast(expr) => expr.cast_span,
             Expression::Call(expr) => expr.func_span,
             Expression::Variable(expr) => expr.identifier.span,
+        }
+    }
     /// Returns the span covering the entire expression (i.e. including the
     /// spans of the arguments as well).
     pub fn full_span(&self) -> InputSpan {
         match self {
             Expression::Assignment(expr) => expr.full_span,
             Expression::Binding(expr) => expr.full_span,
             Expression::Conditional(expr) => expr.full_span,
             Expression::Binary(expr) => expr.full_span,
             Expression::Unary(expr) => expr.full_span,
             Expression::Indexing(expr) => expr.full_span,
             Expression::Slicing(expr) => expr.full_span,
             Expression::Select(expr) => expr.full_span,
             Expression::Literal(expr) => expr.span,
             Expression::Cast(expr) => expr.full_span,
             Expression::Call(expr) => expr.full_span,
             Expression::Variable(expr) => expr.identifier.span,
+        }
+    }
     pub fn parent(&self) -> &ExpressionParent {
         match self {
             Expression::Assignment(expr) => &expr.parent,
             Expression::Binding(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::Literal(expr) => &expr.parent,
             Expression::Cast(expr) => &expr.parent,
             Expression::Call(expr) => &expr.parent,
             Expression::Variable(expr) => &expr.parent,
+        }
+    }
     pub fn parent_mut(&mut self) -> &mut ExpressionParent {
         match self {
             Expression::Assignment(expr) => &mut expr.parent,
             Expression::Binding(expr) => &mut expr.parent,
             Expression::Conditional(expr) => &mut expr.parent,
             Expression::Binary(expr) => &mut expr.parent,
             Expression::Unary(expr) => &mut expr.parent,
             Expression::Indexing(expr) => &mut expr.parent,
             Expression::Slicing(expr) => &mut expr.parent,
             Expression::Select(expr) => &mut expr.parent,
             Expression::Literal(expr) => &mut expr.parent,
             Expression::Cast(expr) => &mut expr.parent,
             Expression::Call(expr) => &mut expr.parent,
             Expression::Variable(expr) => &mut expr.parent,
+        }
+    }
     pub fn parent_expr_id(&self) -> Option<ExpressionId> {
         if let ExpressionParent::Expression(id, _) = self.parent() {
             Some(*id)
         } else {
             None
+        }
+    }
     pub fn type_index(&self) -> i32 {
         match self {
             Expression::Assignment(expr) => expr.type_index,
             Expression::Binding(expr) => expr.type_index,
             Expression::Conditional(expr) => expr.type_index,
             Expression::Binary(expr) => expr.type_index,
             Expression::Unary(expr) => expr.type_index,
             Expression::Indexing(expr) => expr.type_index,
             Expression::Slicing(expr) => expr.type_index,
             Expression::Select(expr) => expr.type_index,
             Expression::Literal(expr) => expr.type_index,
             Expression::Cast(expr) => expr.type_index,
             Expression::Call(expr) => expr.type_index,
             Expression::Variable(expr) => expr.type_index,
+        }
+    }
     pub fn type_index_mut(&mut self) -> &mut i32 {
         match self {
             Expression::Assignment(expr) => &mut expr.type_index,
             Expression::Binding(expr) => &mut expr.type_index,
             Expression::Conditional(expr) => &mut expr.type_index,
             Expression::Binary(expr) => &mut expr.type_index,
             Expression::Unary(expr) => &mut expr.type_index,
             Expression::Indexing(expr) => &mut expr.type_index,
             Expression::Slicing(expr) => &mut expr.type_index,
             Expression::Select(expr) => &mut expr.type_index,
             Expression::Literal(expr) => &mut expr.type_index,
             Expression::Cast(expr) => &mut expr.type_index,
             Expression::Call(expr) => &mut expr.type_index,
             Expression::Variable(expr) => &mut expr.type_index,
+        }
+    }
+}
 #[derive(Debug, Clone, Copy)]
 pub enum AssignmentOperator {
     Set,
     Concatenated,
     Multiplied,
     Divided,
     Remained,
     Added,
     Subtracted,
     ShiftedLeft,
     ShiftedRight,
     BitwiseAnded,
     BitwiseXored,
     BitwiseOred,
+}
 #[derive(Debug, Clone)]
 pub struct AssignmentExpression {
     pub this: AssignmentExpressionId,
     // Parsing
     pub operator_span: InputSpan,
     pub full_span: InputSpan,
     pub left: ExpressionId,
     pub operation: AssignmentOperator,
     pub right: ExpressionId,
     // Validator/Linker
     pub parent: ExpressionParent,
     // Typing
     pub type_index: i32,
+}
 #[derive(Debug, Clone)]
 pub struct BindingExpression {
     pub this: BindingExpressionId,
     // Parsing
     pub operator_span: InputSpan,
     pub full_span: InputSpan,
     pub bound_to: ExpressionId,
     pub bound_from: ExpressionId,
     // Validator/Linker
     pub parent: ExpressionParent,
     // Typing
     pub type_index: i32,
+}
 #[derive(Debug, Clone)]
 pub struct ConditionalExpression {
     pub this: ConditionalExpressionId,
     // Parsing
     pub operator_span: InputSpan,
     pub full_span: InputSpan,
     pub test: ExpressionId,
     pub true_expression: ExpressionId,
     pub false_expression: ExpressionId,
     // Validator/Linking
     pub parent: ExpressionParent,
     // Typing
     pub type_index: i32,
+}
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 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)]
 pub struct BinaryExpression {
     pub this: BinaryExpressionId,
     // Parsing
     pub operator_span: InputSpan,
     pub full_span: InputSpan,
     pub left: ExpressionId,
     pub operation: BinaryOperator,
     pub right: ExpressionId,
     // Validator/Linker
     pub parent: ExpressionParent,
     // Typing
     pub type_index: i32,
+}
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum UnaryOperator {
     Positive,
     Negative,
     BitwiseNot,
     LogicalNot,
+}
 #[derive(Debug, Clone)]
 pub struct UnaryExpression {
     pub this: UnaryExpressionId,
     // Parsing
     pub operator_span: InputSpan,
     pub full_span: InputSpan,
     pub operation: UnaryOperator,
     pub expression: ExpressionId,
     // Validator/Linker
     pub parent: ExpressionParent,
     // Typing
     pub type_index: i32,
+}
 #[derive(Debug, Clone)]
 pub struct IndexingExpression {
     pub this: IndexingExpressionId,
     // Parsing
     pub operator_span: InputSpan,
     pub full_span: InputSpan,
     pub subject: ExpressionId,
     pub index: ExpressionId,
     // Validator/Linker
     pub parent: ExpressionParent,
     // Typing
     pub type_index: i32,
+}
 #[derive(Debug, Clone)]
 pub struct SlicingExpression {
     pub this: SlicingExpressionId,
     // Parsing
     pub slicing_span: InputSpan, // from '[' to ']'
     pub full_span: InputSpan, // includes subject
     pub subject: ExpressionId,
     pub from_index: ExpressionId,
     pub to_index: ExpressionId,
     // Validator/Linker
     pub parent: ExpressionParent,
     // Typing
     pub type_index: i32,
+}
 #[derive(Debug, Clone)]
 pub enum SelectKind {
     StructField(Identifier),
     TupleMember(u64), // u64 is overkill, but space is taken up by `StructField` variant anyway
+}
 #[derive(Debug, Clone)]
 pub struct SelectExpression {
     pub this: SelectExpressionId,
     // Parsing
     pub operator_span: InputSpan, // of the '.'
     pub full_span: InputSpan, // includes subject and field
     pub subject: ExpressionId,
     pub kind: SelectKind,
     // Validator/Linker
     pub parent: ExpressionParent,
     // Typing
     pub type_index: i32,
+}
 #[derive(Debug, Clone)]
 pub struct CastExpression {
     pub this: CastExpressionId,
     // Parsing
     pub cast_span: InputSpan, // of the "cast" keyword,
     pub full_span: InputSpan, // includes the cast subject
     pub to_type: ParserType,
     pub subject: ExpressionId,
     // Validator/linker
     pub parent: ExpressionParent,
     // Typing
     pub type_index: i32,
+}
 #[derive(Debug, Clone)]
 pub struct CallExpression {
     pub this: CallExpressionId,
     // Parsing
     pub func_span: InputSpan, // of the function name
     pub full_span: InputSpan, // includes the arguments and parentheses
     pub parser_type: ParserType, // of the function call, not the return type
     pub method: Method,
     pub arguments: Vec<ExpressionId>,
     pub procedure: ProcedureDefinitionId,
     // Validator/Linker
     pub parent: ExpressionParent,
     // Typing
     pub type_index: i32,
+}
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub enum Method {
     // Builtin function, accessible by programmer
     Get,
     Put,
     Fires,
     Create,
     Length,
     Assert,
     Print,
     // Builtin function, not accessible by programmer
     SelectStart, // SelectStart(total_num_cases, total_num_ports)
     SelectRegisterCasePort, // SelectRegisterCasePort(case_index, port_index, port_id)
     SelectWait, // SelectWait() -> u32
     // Builtin component,
     ComponentRandomU32,
     ComponentTcpClient,
     ComponentTcpListener,
     // User-defined
     UserFunction,
     UserComponent,
+}
 impl Method {
     pub(crate) fn is_public_builtin(&self) -> bool {
         use Method::*;
         match self {
             Get | Put | Fires | Create | Length | Assert | Print => true,
             ComponentRandomU32 | ComponentTcpClient => true,
+            ComponentRandomU32 | ComponentTcpClient | ComponentTcpListener => true,
             _ => false,
+        }
+    }
     pub(crate) fn is_user_defined(&self) -> bool {
         use Method::*;
         match self {
             UserFunction | UserComponent => true,
             _ => false,
+        }
+    }
+}
 #[derive(Debug, Clone)]
 pub struct LiteralExpression {
     pub this: LiteralExpressionId,
     // Parsing
     pub span: InputSpan,
     pub value: Literal,
     // Validator/Linker
     pub parent: ExpressionParent,
     // Typing
     pub type_index: i32,
+}
 #[derive(Debug, Clone)]
 pub enum Literal {
     Null, // message
     True,
     False,
     Character(char),
     Bytestring(Vec<u8>),
     String(StringRef<'static>),
     Integer(LiteralInteger),
     Struct(LiteralStruct),
     Enum(LiteralEnum),
     Union(LiteralUnion),
     Array(Vec<ExpressionId>),
     Tuple(Vec<ExpressionId>),
+}
 impl Literal {
     pub(crate) fn as_struct(&self) -> &LiteralStruct {
         if let Literal::Struct(literal) = self{
             literal
         } else {
             unreachable!("Attempted to obtain {:?} as Literal::Struct", self)
+        }
+    }
     pub(crate) fn as_enum(&self) -> &LiteralEnum {
         if let Literal::Enum(literal) = self {
             literal
         } else {
             unreachable!("Attempted to obtain {:?} as Literal::Enum", self)
+        }
+    }
     pub(crate) fn as_union(&self) -> &LiteralUnion {
         if let Literal::Union(literal) = self {
             literal
         } else {
             unreachable!("Attempted to obtain {:?} as Literal::Union", self)
+        }
+    }
+}
 #[derive(Debug, Clone)]
 pub struct LiteralInteger {
     pub(crate) unsigned_value: u64,
     pub(crate) negated: bool, // for constant expression evaluation, TODO: @Int
+}
 #[derive(Debug, Clone)]
 pub struct LiteralStructField {
     // Phase 1: parser
     pub(crate) identifier: Identifier,
     pub(crate) value: ExpressionId,
     // Phase 2: linker
     pub(crate) field_idx: usize, // in struct definition
+}
 #[derive(Debug, Clone)]
 pub struct LiteralStruct {
     // Phase 1: parser
     pub(crate) parser_type: ParserType,
     pub(crate) fields: Vec<LiteralStructField>,
     pub(crate) definition: DefinitionId,
+}
 #[derive(Debug, Clone)]
 pub struct LiteralEnum {
     // Phase 1: parser
     pub(crate) parser_type: ParserType,
     pub(crate) variant: Identifier,
     pub(crate) definition: DefinitionId,
     // Phase 2: linker
     pub(crate) variant_idx: usize, // as present in the type table
+}
 #[derive(Debug, Clone)]
 pub struct LiteralUnion {
     // Phase 1: parser
     pub(crate) parser_type: ParserType,
     pub(crate) variant: Identifier,
     pub(crate) values: Vec<ExpressionId>,
     pub(crate) definition: DefinitionId,
     // Phase 2: linker
     pub(crate) variant_idx: usize, // as present in type table
+}
 #[derive(Debug, Clone)]
 pub struct VariableExpression {
     pub this: VariableExpressionId,
     // Parsing
     pub identifier: Identifier,
     // Validator/Linker
     pub declaration: Option<VariableId>,
     pub used_as_binding_target: bool,
     pub parent: ExpressionParent,
     // Typing
     pub type_index: i32,
+}
@@ \ No newline at end of file @@

src/protocol/eval/executor.rs

➞

Show inline comments

@@ @@ -5,1162 +5,1162 @@ use super::value::*; @@
 use super::store::*;
 use super::error::*;
 use crate::protocol::*;
 use crate::protocol::ast::*;
 use crate::protocol::type_table::*;
 macro_rules! debug_enabled { () => { false }; }
 macro_rules! debug_log {
     ($format:literal) => {
         enabled_debug_print!(false, "exec", $format);
     };
     ($format:literal, $($args:expr),*) => {
         enabled_debug_print!(false, "exec", $format, $($args),*);
     };
+}
 #[derive(Debug, Clone)]
 pub(crate) enum ExprInstruction {
     EvalExpr(ExpressionId),
     PushValToFront,
+}
 #[derive(Debug, Clone)]
 pub(crate) struct Frame {
     pub(crate) definition: ProcedureDefinitionId,
     pub(crate) monomorph_index: usize,
     pub(crate) position: StatementId,
     pub(crate) expr_stack: VecDeque<ExprInstruction>, // hack for expression evaluation, evaluated by popping from back
     pub(crate) expr_values: VecDeque<Value>, // hack for expression results, evaluated by popping from front/back
     pub(crate) max_stack_size: u32,
+}
 impl Frame {
     /// Creates a new execution frame. Does not modify the stack in any way.
     pub fn new(heap: &Heap, definition_id: ProcedureDefinitionId, _monomorph_type_id: TypeId, monomorph_index: u32) -> Self {
         let definition = &heap[definition_id];
         let outer_scope_id = definition.scope;
         let first_statement_id = definition.body;
         // Another not-so-pretty thing that has to be replaced somewhere in the
         // future...
         fn determine_max_stack_size(heap: &Heap, scope_id: ScopeId, max_size: &mut u32) {
             let scope = &heap[scope_id];
             // Check current block
             let cur_size = scope.next_unique_id_in_scope as u32;
             if cur_size > *max_size { *max_size = cur_size; }
             // And child blocks
             for child_scope in &scope.nested {
                 determine_max_stack_size(heap, *child_scope, max_size);
+            }
+        }
         let mut max_stack_size = 0;
         determine_max_stack_size(heap, outer_scope_id, &mut max_stack_size);
         Frame{
             definition: definition_id,
             monomorph_index: monomorph_index as usize,
             position: first_statement_id.upcast(),
             expr_stack: VecDeque::with_capacity(128),
             expr_values: VecDeque::with_capacity(128),
             max_stack_size,
+        }
+    }
     /// Prepares a single expression for execution. This involves walking the
     /// expression tree and putting them in the `expr_stack` such that
     /// continuously popping from its back will evaluate the expression. The
     /// results of each expression will be stored by pushing onto `expr_values`.
     pub fn prepare_single_expression(&mut self, heap: &Heap, expr_id: ExpressionId) {
         debug_assert!(self.expr_stack.is_empty());
         self.expr_values.clear(); // May not be empty if last expression result(s) were discarded
         self.serialize_expression(heap, expr_id);
+    }
     /// Prepares multiple expressions for execution (i.e. evaluating all
     /// function arguments or all elements of an array/union literal). Per
     /// expression this works the same as `prepare_single_expression`. However
     /// after each expression is evaluated we insert a `PushValToFront`
     /// instruction
     pub fn prepare_multiple_expressions(&mut self, heap: &Heap, expr_ids: &[ExpressionId]) {
         debug_assert!(self.expr_stack.is_empty());
         self.expr_values.clear();
         for expr_id in expr_ids {
             self.expr_stack.push_back(ExprInstruction::PushValToFront);
             self.serialize_expression(heap, *expr_id);
+        }
+    }
     /// Performs depth-first serialization of expression tree. Let's not care
     /// about performance for a temporary runtime implementation
     fn serialize_expression(&mut self, heap: &Heap, id: ExpressionId) {
         self.expr_stack.push_back(ExprInstruction::EvalExpr(id));
         match &heap[id] {
             Expression::Assignment(expr) => {
                 self.serialize_expression(heap, expr.left);
                 self.serialize_expression(heap, expr.right);
             },
             Expression::Binding(expr) => {
                 self.serialize_expression(heap, expr.bound_to);
                 self.serialize_expression(heap, expr.bound_from);
             },
             Expression::Conditional(expr) => {
                 self.serialize_expression(heap, expr.test);
             },
             Expression::Binary(expr) => {
                 self.serialize_expression(heap, expr.left);
                 self.serialize_expression(heap, expr.right);
             },
             Expression::Unary(expr) => {
                 self.serialize_expression(heap, expr.expression);
             },
             Expression::Indexing(expr) => {
                 self.serialize_expression(heap, expr.index);
                 self.serialize_expression(heap, expr.subject);
             },
             Expression::Slicing(expr) => {
                 self.serialize_expression(heap, expr.from_index);
                 self.serialize_expression(heap, expr.to_index);
                 self.serialize_expression(heap, expr.subject);
             },
             Expression::Select(expr) => {
                 self.serialize_expression(heap, expr.subject);
             },
             Expression::Literal(expr) => {
                 // Here we only care about literals that have subexpressions
                 match &expr.value {
                     Literal::Null | Literal::True | Literal::False |
                     Literal::Character(_) | Literal::Bytestring(_) | Literal::String(_) |
                     Literal::Integer(_) | Literal::Enum(_) => {
                         // No subexpressions
                     },
                     Literal::Struct(literal) => {
                         // Note: fields expressions are evaluated in programmer-
                         // specified order. But struct construction expects them
                         // in type-defined order. I might want to come back to
                         // this.
                         let mut _num_pushed = 0;
                         for want_field_idx in 0..literal.fields.len() {
                             for field in &literal.fields {
                                 if field.field_idx == want_field_idx {
                                     _num_pushed += 1;
                                     self.expr_stack.push_back(ExprInstruction::PushValToFront);
                                     self.serialize_expression(heap, field.value);
+                                }
+                            }
+                        }
                         debug_assert_eq!(_num_pushed, literal.fields.len())
                     },
                     Literal::Union(literal) => {
                         for value_expr_id in &literal.values {
                             self.expr_stack.push_back(ExprInstruction::PushValToFront);
                             self.serialize_expression(heap, *value_expr_id);
+                        }
                     },
                     Literal::Array(value_expr_ids) => {
                         for value_expr_id in value_expr_ids {
                             self.expr_stack.push_back(ExprInstruction::PushValToFront);
                             self.serialize_expression(heap, *value_expr_id);
+                        }
                     },
                     Literal::Tuple(value_expr_ids) => {
                         for value_expr_id in value_expr_ids {
                             self.expr_stack.push_back(ExprInstruction::PushValToFront);
                             self.serialize_expression(heap, *value_expr_id);
+                        }
+                    }
+                }
             },
             Expression::Cast(expr) => {
                 self.serialize_expression(heap, expr.subject);
+            }
             Expression::Call(expr) => {
                 for arg_expr_id in &expr.arguments {
                     self.expr_stack.push_back(ExprInstruction::PushValToFront);
                     self.serialize_expression(heap, *arg_expr_id);
+                }
             },
             Expression::Variable(_expr) => {
                 // No subexpressions
+            }
+        }
+    }
+}
 pub type EvalResult = Result<EvalContinuation, EvalError>;
 #[derive(Debug)]
 pub enum EvalContinuation {
     // Returned in both sync and non-sync modes
     Stepping,
     // Returned only in sync mode
     BranchInconsistent,
     SyncBlockEnd,
     NewFork,
     BlockFires(PortId),
     BlockGet(ExpressionId, PortId),
     Put(ExpressionId, PortId, ValueGroup),
     SelectStart(u32, u32), // (num_cases, num_ports_total)
     SelectRegisterPort(ExpressionId, u32, u32, PortId), // (call_expr_id, case_index, port_index_in_case, port_id)
     SelectWait, // wait until select can continue
     // Returned only in non-sync mode
     ComponentTerminated,
     SyncBlockStart,
     NewComponent(ProcedureDefinitionId, TypeId, ValueGroup),
     NewChannel,
+}
 // Note: cloning is fine, methinks. cloning all values and the heap regions then
 // we end up with valid "pointers" to heap regions.
 #[derive(Debug, Clone)]
 pub struct Prompt {
     pub(crate) frames: Vec<Frame>,
     pub(crate) store: Store,
+}
 impl Prompt {
     pub fn new(types: &TypeTable, heap: &Heap, def: ProcedureDefinitionId, type_id: TypeId, args: ValueGroup) -> Self {
         let mut prompt = Self{
             frames: Vec::new(),
             store: Store::new(),
         };
         // Maybe do typechecking in the future?
         let monomorph_index = types.get_monomorph(type_id).variant.as_procedure().monomorph_index;
         let new_frame = Frame::new(heap, def, type_id, monomorph_index);
         let max_stack_size = new_frame.max_stack_size;
         prompt.frames.push(new_frame);
         args.into_store(&mut prompt.store);
         prompt.store.reserve_stack(max_stack_size);
         prompt
+    }
     /// Big 'ol function right here. Didn't want to break it up unnecessarily.
     /// It consists of, in sequence: executing any expressions that should be
     /// executed before the next statement can be evaluated, then a section that
     /// performs debug printing, and finally a section that takes the next
     /// statement and executes it. If the statement requires any expressions to
     /// be evaluated, then they will be added such that the next time `step` is
     /// called, all of these expressions are indeed evaluated.
     pub(crate) fn step(&mut self, types: &TypeTable, heap: &Heap, modules: &[Module], ctx: &mut impl RunContext) -> EvalResult {
         // Helper function to transfer multiple values from the expression value
         // array into a heap region (e.g. constructing arrays or structs).
         fn transfer_expression_values_front_into_heap(cur_frame: &mut Frame, store: &mut Store, num_values: usize) -> HeapPos {
             let heap_pos = store.alloc_heap();
             // Do the transformation first (because Rust...)
             for val_idx in 0..num_values {
                 cur_frame.expr_values[val_idx] = store.read_take_ownership(cur_frame.expr_values[val_idx].clone());
+            }
             // And now transfer to the heap region
             let values = &mut store.heap_regions[heap_pos as usize].values;
             debug_assert!(values.is_empty());
             values.reserve(num_values);
             for _ in 0..num_values {
                 values.push(cur_frame.expr_values.pop_front().unwrap());
+            }
             heap_pos
+        }
         // Helper function to make sure that an index into an aray is valid.
         fn array_inclusive_index_is_invalid(store: &Store, array_heap_pos: u32, idx: i64) -> bool {
             let array_len = store.heap_regions[array_heap_pos as usize].values.len();
             return idx < 0 || idx >= array_len as i64;
+        }
         fn array_exclusive_index_is_invalid(store: &Store, array_heap_pos: u32, idx: i64) -> bool {
             let array_len = store.heap_regions[array_heap_pos as usize].values.len();
             return idx < 0 || idx > array_len as i64;
+        }
         fn construct_array_error(prompt: &Prompt, modules: &[Module], heap: &Heap, expr_id: ExpressionId, heap_pos: u32, idx: i64) -> EvalError {
             let array_len = prompt.store.heap_regions[heap_pos as usize].values.len();
             return EvalError::new_error_at_expr(
                 prompt, modules, heap, expr_id,
                 format!("index {} is out of bounds: array length is {}", idx, array_len)
+            )
+        }
         // Checking if we're at the end of execution
         let cur_frame = self.frames.last_mut().unwrap();
         if cur_frame.position.is_invalid() {
             if heap[cur_frame.definition].kind == ProcedureKind::Function {
                 todo!("End of function without return, return an evaluation error");
+            }
             return Ok(EvalContinuation::ComponentTerminated);
+        }
         debug_log!("Taking step in '{}'", heap[cur_frame.definition].identifier.value.as_str());
         // Execute all pending expressions
         while !cur_frame.expr_stack.is_empty() {
             let next = cur_frame.expr_stack.pop_back().unwrap();
             debug_log!("Expr stack: {:?}", next);
             match next {
                 ExprInstruction::PushValToFront => {
                     cur_frame.expr_values.rotate_right(1);
                 },
                 ExprInstruction::EvalExpr(expr_id) => {
                     let expr = &heap[expr_id];
                     match expr {
                         Expression::Assignment(expr) => {
                             let to = cur_frame.expr_values.pop_back().unwrap().as_ref();
                             let rhs = cur_frame.expr_values.pop_back().unwrap();
                             // Note: although not pretty, the assignment operator takes ownership
                             // of the right-hand side value when possible. So we do not drop the
                             // rhs's optionally owned heap data.
                             let rhs = self.store.read_take_ownership(rhs);
                             apply_assignment_operator(&mut self.store, to, expr.operation, rhs);
                         },
                         Expression::Binding(_expr) => {
                             let bind_to = cur_frame.expr_values.pop_back().unwrap();
                             let bind_from = cur_frame.expr_values.pop_back().unwrap();
                             let bind_to_heap_pos = bind_to.get_heap_pos();
                             let bind_from_heap_pos = bind_from.get_heap_pos();
                             let result = apply_binding_operator(&mut self.store, bind_to, bind_from);
                             self.store.drop_value(bind_to_heap_pos);
                             self.store.drop_value(bind_from_heap_pos);
                             cur_frame.expr_values.push_back(Value::Bool(result));
                         },
                         Expression::Conditional(expr) => {
                             // Evaluate testing expression, then extend the
                             // expression stack with the appropriate expression
                             let test_result = cur_frame.expr_values.pop_back().unwrap().as_bool();
                             if test_result {
                                 cur_frame.serialize_expression(heap, expr.true_expression);
                             } else {
                                 cur_frame.serialize_expression(heap, expr.false_expression);
+                            }
                         },
                         Expression::Binary(expr) => {
                             let lhs = cur_frame.expr_values.pop_back().unwrap();
                             let rhs = cur_frame.expr_values.pop_back().unwrap();
                             let result = apply_binary_operator(&mut self.store, &lhs, expr.operation, &rhs);
                             cur_frame.expr_values.push_back(result);
                             self.store.drop_value(lhs.get_heap_pos());
                             self.store.drop_value(rhs.get_heap_pos());
                         },
                         Expression::Unary(expr) => {
                             let val = cur_frame.expr_values.pop_back().unwrap();
                             let result = apply_unary_operator(&mut self.store, expr.operation, &val);
                             cur_frame.expr_values.push_back(result);
                             self.store.drop_value(val.get_heap_pos());
                         },
                         Expression::Indexing(_expr) => {
                             // Evaluate index. Never heap allocated so we do
                             // not have to drop it.
                             let index = cur_frame.expr_values.pop_back().unwrap();
                             let index = self.store.maybe_read_ref(&index);
                             debug_assert!(index.is_integer());
                             let index = if index.is_signed_integer() {
                                 index.as_signed_integer() as i64
                             } else {
                                 index.as_unsigned_integer() as i64
                             };
                             let subject = cur_frame.expr_values.pop_back().unwrap();
                             let (deallocate_heap_pos, value_to_push) = match subject {
                                 Value::Ref(value_ref) => {
                                     // Our expression stack value is a reference to something that
                                     // exists in the normal stack/heap. We don't want to deallocate
                                     // this thing. Rather we want to return a reference to it.
                                     let subject = self.store.read_ref(value_ref);
                                     let subject_heap_pos = match subject {
                                         Value::String(v) => *v,
                                         Value::Array(v) => *v,
                                         Value::Message(v) => *v,
                                         _ => unreachable!(),
                                     };
                                     if array_inclusive_index_is_invalid(&self.store, subject_heap_pos, index) {
                                         return Err(construct_array_error(self, modules, heap, expr_id, subject_heap_pos, index));
+                                    }
                                     (None, Value::Ref(ValueId::Heap(subject_heap_pos, index as u32)))
                                 },
                                 _ => {
                                     // Our value lives on the expression stack, hence we need to
                                     // clone whatever we're referring to. Then drop the subject.
                                     let subject_heap_pos = match &subject {
                                         Value::String(v) => *v,
                                         Value::Array(v) => *v,
                                         Value::Message(v) => *v,
                                         _ => unreachable!(),
                                     };
                                     if array_inclusive_index_is_invalid(&self.store, subject_heap_pos, index) {
                                         return Err(construct_array_error(self, modules, heap, expr_id, subject_heap_pos, index));
+                                    }
                                     let subject_indexed = Value::Ref(ValueId::Heap(subject_heap_pos, index as u32));
                                     (Some(subject_heap_pos), self.store.clone_value(subject_indexed))
                                 },
                             };
                             cur_frame.expr_values.push_back(value_to_push);
                             self.store.drop_value(deallocate_heap_pos);
                         },
                         Expression::Slicing(expr) => {
                             // Evaluate indices
                             let from_index = cur_frame.expr_values.pop_back().unwrap();
                             let from_index = self.store.maybe_read_ref(&from_index);
                             let to_index = cur_frame.expr_values.pop_back().unwrap();
                             let to_index = self.store.maybe_read_ref(&to_index);
                             debug_assert!(from_index.is_integer() && to_index.is_integer());
                             let from_index = if from_index.is_signed_integer() {
                                 from_index.as_signed_integer()
                             } else {
                                 from_index.as_unsigned_integer() as i64
                             };
                             let to_index = if to_index.is_signed_integer() {
                                 to_index.as_signed_integer()
                             } else {
                                 to_index.as_unsigned_integer() as i64
                             };
                             // Dereference subject if needed
                             let subject = cur_frame.expr_values.pop_back().unwrap();
                             let deref_subject = self.store.maybe_read_ref(&subject);
                             // Slicing needs to produce a copy anyway (with the
                             // current evaluator implementation)
                             enum ValueKind{ Array, String, Message }
                             let (value_kind, array_heap_pos) = match deref_subject {
                                 Value::Array(v) => (ValueKind::Array, *v),
                                 Value::String(v) => (ValueKind::String, *v),
                                 Value::Message(v) => (ValueKind::Message, *v),
                                 _ => unreachable!()
                             };
                             if array_inclusive_index_is_invalid(&self.store, array_heap_pos, from_index) {
                                 return Err(construct_array_error(self, modules, heap, expr.from_index, array_heap_pos, from_index));
+                            }
                             if array_exclusive_index_is_invalid(&self.store, array_heap_pos, to_index) {
                                 return Err(construct_array_error(self, modules, heap, expr.to_index, array_heap_pos, to_index));
+                            }
                             // Again: would love to push directly, but rust...
                             let new_heap_pos = self.store.alloc_heap();
                             debug_assert!(self.store.heap_regions[new_heap_pos as usize].values.is_empty());
                             if to_index > from_index {
                                 let from_index = from_index as usize;
                                 let to_index = to_index as usize;
                                 let mut values = Vec::with_capacity(to_index - from_index);
                                 for idx in from_index..to_index {
                                     let value = self.store.heap_regions[array_heap_pos as usize].values[idx].clone();
                                     values.push(self.store.clone_value(value));
+                                }
                                 self.store.heap_regions[new_heap_pos as usize].values = values;
                             } // else: empty range
                             cur_frame.expr_values.push_back(match value_kind {
                                 ValueKind::Array => Value::Array(new_heap_pos),
                                 ValueKind::String => Value::String(new_heap_pos),
                                 ValueKind::Message => Value::Message(new_heap_pos),
                             });
                             // Dropping the original subject, because we don't
                             // want to drop something on the stack
                             self.store.drop_value(subject.get_heap_pos());
                         },
                         Expression::Select(expr) => {
                             let subject= cur_frame.expr_values.pop_back().unwrap();
                             let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
                             let field_idx = mono_data.expr_info[expr.type_index as usize].variant.as_select() as u32;
                             // Note: same as above: clone if value lives on expr stack, simply
                             // refer to it if it already lives on the stack/heap.
                             let (deallocate_heap_pos, value_to_push) = match subject {
                                 Value::Ref(value_ref) => {
                                     let subject = self.store.read_ref(value_ref);
                                     let subject_heap_pos = match expr.kind {
                                         SelectKind::StructField(_) => subject.as_struct(),
                                         SelectKind::TupleMember(_) => subject.as_tuple(),
                                     };
                                     (None, Value::Ref(ValueId::Heap(subject_heap_pos, field_idx)))
                                 },
                                 _ => {
                                     let subject_heap_pos = match expr.kind {
                                         SelectKind::StructField(_) => subject.as_struct(),
                                         SelectKind::TupleMember(_) => subject.as_tuple(),
                                     };
                                     let subject_indexed = Value::Ref(ValueId::Heap(subject_heap_pos, field_idx));
                                     (Some(subject_heap_pos), self.store.clone_value(subject_indexed))
                                 },
                             };
                             cur_frame.expr_values.push_back(value_to_push);
                             self.store.drop_value(deallocate_heap_pos);
                         },
                         Expression::Literal(expr) => {
                             let value = match &expr.value {
                                 Literal::Null => Value::Null,
                                 Literal::True => Value::Bool(true),
                                 Literal::False => Value::Bool(false),
                                 Literal::Character(lit_value) => Value::Char(*lit_value),
                                 Literal::Bytestring(lit_value) => {
                                     let heap_pos = self.store.alloc_heap();
                                     let values = &mut self.store.heap_regions[heap_pos as usize].values;
                                     debug_assert!(values.is_empty());
                                     values.reserve(lit_value.len());
                                     for byte in lit_value {
                                         values.push(Value::UInt8(*byte));
+                                    }
                                     Value::Array(heap_pos)
+                                }
                                 Literal::String(lit_value) => {
                                     let heap_pos = self.store.alloc_heap();
                                     let values = &mut self.store.heap_regions[heap_pos as usize].values;
                                     let value = lit_value.as_str();
                                     debug_assert!(values.is_empty());
                                     values.reserve(value.len());
                                     for character in value.as_bytes() {
                                         debug_assert!(character.is_ascii());
                                         values.push(Value::Char(*character as char));
+                                    }
                                     Value::String(heap_pos)
+                                }
                                 Literal::Integer(lit_value) => {
                                     use ConcreteTypePart as CTP;
                                     let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
                                     let type_id = mono_data.expr_info[expr.type_index as usize].type_id;
                                     let concrete_type = &types.get_monomorph(type_id).concrete_type;
                                     debug_assert_eq!(concrete_type.parts.len(), 1);
                                     match concrete_type.parts[0] {
                                         CTP::UInt8  => Value::UInt8(lit_value.unsigned_value as u8),
                                         CTP::UInt16 => Value::UInt16(lit_value.unsigned_value as u16),
                                         CTP::UInt32 => Value::UInt32(lit_value.unsigned_value as u32),
                                         CTP::UInt64 => Value::UInt64(lit_value.unsigned_value as u64),
                                         CTP::SInt8  => Value::SInt8(lit_value.unsigned_value as i8),
                                         CTP::SInt16 => Value::SInt16(lit_value.unsigned_value as i16),
                                         CTP::SInt32 => Value::SInt32(lit_value.unsigned_value as i32),
                                         CTP::SInt64 => Value::SInt64(lit_value.unsigned_value as i64),
                                         _ => unreachable!("got concrete type {:?} for integer literal at expr {:?}", concrete_type, expr_id),
+                                    }
+                                }
                                 Literal::Struct(lit_value) => {
                                     let heap_pos = transfer_expression_values_front_into_heap(
                                         cur_frame, &mut self.store, lit_value.fields.len()
                                     );
                                     Value::Struct(heap_pos)
+                                }
                                 Literal::Enum(lit_value) => {
                                     Value::Enum(lit_value.variant_idx as i64)
+                                }
                                 Literal::Union(lit_value) => {
                                     let heap_pos = transfer_expression_values_front_into_heap(
                                         cur_frame, &mut self.store, lit_value.values.len()
                                     );
                                     Value::Union(lit_value.variant_idx as i64, heap_pos)
+                                }
                                 Literal::Array(lit_value) => {
                                     let heap_pos = transfer_expression_values_front_into_heap(
                                         cur_frame, &mut self.store, lit_value.len()
                                     );
                                     Value::Array(heap_pos)
+                                }
                                 Literal::Tuple(lit_value) => {
                                     let heap_pos = transfer_expression_values_front_into_heap(
                                         cur_frame, &mut self.store, lit_value.len()
                                     );
                                     Value::Tuple(heap_pos)
+                                }
                             };
                             cur_frame.expr_values.push_back(value);
                         },
                         Expression::Cast(expr) => {
                             let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
                             let type_id = mono_data.expr_info[expr.type_index as usize].type_id;
                             let concrete_type = &types.get_monomorph(type_id).concrete_type;
                             // Typechecking reduced this to two cases: either we
                             // have casting noop (same types), or we're casting
                             // between integer/bool/char types.
                             let subject = cur_frame.expr_values.pop_back().unwrap();
                             match apply_casting(&mut self.store, concrete_type, &subject) {
                                 Ok(value) => cur_frame.expr_values.push_back(value),
                                 Err(msg) => {
                                     return Err(EvalError::new_error_at_expr(self, modules, heap, expr.this.upcast(), msg));
+                                }
+                            }
                             self.store.drop_value(subject.get_heap_pos());
+                        }
                         Expression::Call(expr) => {
                             // If we're dealing with a builtin we don't do any
                             // fancy shenanigans at all, just push the result.
                             match expr.method {
                                 Method::Get => {
                                     let value = cur_frame.expr_values.pop_front().unwrap();
                                     let value = self.store.maybe_read_ref(&value).clone();
                                     let port_id = if let Value::Input(port_id) = value {
                                         port_id
                                     } else {
                                         unreachable!("executor calling 'get' on value {:?}", value)
                                     };
                                     match ctx.performed_get(port_id) {
                                         Some(result) => {
                                             // We have the result. Merge the `ValueGroup` with the
                                             // stack/heap storage.
                                             debug_assert_eq!(result.values.len(), 1);
                                             result.into_stack(&mut cur_frame.expr_values, &mut self.store);
                                         },
                                         None => {
                                             // Don't have the result yet, prepare the expression to
                                             // get run again after we've received a message.
                                             cur_frame.expr_values.push_front(value.clone());
                                             cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr_id));
                                             return Ok(EvalContinuation::BlockGet(expr_id, port_id));
+                                        }
+                                    }
                                 },
                                 Method::Put => {
                                     let port_value = cur_frame.expr_values.pop_front().unwrap();
                                     let deref_port_value = self.store.maybe_read_ref(&port_value).clone();
                                     let port_id = if let Value::Output(port_id) = deref_port_value {
                                         port_id
                                     } else {
                                         unreachable!("executor calling 'put' on value {:?}", deref_port_value)
                                     };
                                     let msg_value = cur_frame.expr_values.pop_front().unwrap();
                                     let deref_msg_value = self.store.maybe_read_ref(&msg_value).clone();
                                     if ctx.performed_put(port_id) {
                                         // We're fine, deallocate in case the expression value stack
                                         // held an owned value
                                         self.store.drop_value(msg_value.get_heap_pos());
                                     } else {
                                         // Prepare to execute again
                                         cur_frame.expr_values.push_front(msg_value);
                                         cur_frame.expr_values.push_front(port_value);
                                         cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr_id));
                                         let value_group = ValueGroup::from_store(&self.store, &[deref_msg_value]);
                                         return Ok(EvalContinuation::Put(expr_id, port_id, value_group));
+                                    }
                                 },
                                 Method::Fires => {
                                     let port_value = cur_frame.expr_values.pop_front().unwrap();
                                     let port_value_deref = self.store.maybe_read_ref(&port_value).clone();
                                     let port_id = port_value_deref.as_port_id();
                                     match ctx.fires(port_id) {
                                         None => {
                                             cur_frame.expr_values.push_front(port_value);
                                             cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr_id));
                                             return Ok(EvalContinuation::BlockFires(port_id));
                                         },
                                         Some(value) => {
                                             cur_frame.expr_values.push_back(value);
+                                        }
+                                    }
                                 },
                                 Method::Create => {
                                     let length_value = cur_frame.expr_values.pop_front().unwrap();
                                     let length_value = self.store.maybe_read_ref(&length_value);
                                     let length = if length_value.is_signed_integer() {
                                         let length_value = length_value.as_signed_integer();
                                         if length_value < 0 {
                                             return Err(EvalError::new_error_at_expr(
                                                 self, modules, heap, expr_id,
                                                 format!("got length '{}', can only create a message with a non-negative length", length_value)
                                             ));
+                                        }
                                         length_value as u64
                                     } else {
                                         debug_assert!(length_value.is_unsigned_integer());
                                         length_value.as_unsigned_integer()
                                     };
                                     let heap_pos = self.store.alloc_heap();
                                     let values = &mut self.store.heap_regions[heap_pos as usize].values;
                                     debug_assert!(values.is_empty());
                                     values.resize(length as usize, Value::UInt8(0));
                                     cur_frame.expr_values.push_back(Value::Message(heap_pos));
                                 },
                                 Method::Length => {
                                     let value = cur_frame.expr_values.pop_front().unwrap();
                                     let value_heap_pos = value.get_heap_pos();
                                     let value = self.store.maybe_read_ref(&value);
                                     let heap_pos = match value {
                                         Value::Array(pos) => *pos,
                                         Value::String(pos) => *pos,
                                         _ => unreachable!("length(...) on {:?}", value),
                                     };
                                     let len = self.store.heap_regions[heap_pos as usize].values.len();
                                     // TODO: @PtrInt
                                     cur_frame.expr_values.push_back(Value::UInt32(len as u32));
                                     self.store.drop_value(value_heap_pos);
                                 },
                                 Method::Assert => {
                                     let value = cur_frame.expr_values.pop_front().unwrap();
                                     let value = self.store.maybe_read_ref(&value).clone();
                                     if !value.as_bool() {
                                         return Ok(EvalContinuation::BranchInconsistent)
+                                    }
                                 },
                                 Method::Print => {
                                     // Convert the runtime-variant of a string
                                     // into an actual string.
                                     let value = cur_frame.expr_values.pop_front().unwrap();
                                     let is_literal_string = value.get_heap_pos().is_some();
                                     let value = self.store.maybe_read_ref(&value);
                                     let value_heap_pos = value.as_string();
                                     let elements = &self.store.heap_regions[value_heap_pos as usize].values;
                                     let mut message = String::with_capacity(elements.len());
                                     for element in elements {
                                         message.push(element.as_char());
+                                    }
                                     // Drop the heap-allocated value from the
                                     // store
                                     if is_literal_string {
                                         self.store.drop_heap_pos(value_heap_pos);
+                                    }
                                     println!("{}", message);
                                 },
                                 Method::SelectStart => {
                                     let num_cases = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_uint32();
                                     let num_ports = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_uint32();
                                     return Ok(EvalContinuation::SelectStart(num_cases, num_ports));
                                 },
                                 Method::SelectRegisterCasePort => {
                                     let case_index = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_uint32();
                                     let port_index = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_uint32();
                                     let port_value = self.store.maybe_read_ref(&cur_frame.expr_values.pop_front().unwrap()).as_port_id();
                                     return Ok(EvalContinuation::SelectRegisterPort(expr_id, case_index, port_index, port_value));
                                 },
                                 Method::SelectWait => {
                                     match ctx.performed_select_wait() {
                                         Some(select_index) => {
                                             cur_frame.expr_values.push_back(Value::UInt32(select_index));
                                         },
                                         None => {
                                             cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr.this.upcast()));
                                             return Ok(EvalContinuation::SelectWait)
                                         },
+                                    }
                                 },
                                 Method::ComponentRandomU32 | Method::ComponentTcpClient => {
+                                Method::ComponentRandomU32 | Method::ComponentTcpClient | Method::ComponentTcpListener => {
                                     debug_assert_eq!(heap[expr.procedure].parameters.len(), cur_frame.expr_values.len());
                                     debug_assert_eq!(heap[cur_frame.position].as_new().expression, expr.this);
                                 },
                                 Method::UserComponent => {
                                     // This is actually handled by the evaluation
                                     // of the statement.
                                     debug_assert_eq!(heap[expr.procedure].parameters.len(), cur_frame.expr_values.len());
                                     debug_assert_eq!(heap[cur_frame.position].as_new().expression, expr.this);
                                 },
                                 Method::UserFunction => {
                                     // Push a new frame. Note that all expressions have
                                     // been pushed to the front, so they're in the order
                                     // of the definition.
                                     let num_args = expr.arguments.len();
                                     // Determine stack boundaries
                                     let cur_stack_boundary = self.store.cur_stack_boundary;
                                     let new_stack_boundary = self.store.stack.len();
                                     // Push new boundary and function arguments for new frame
                                     self.store.stack.push(Value::PrevStackBoundary(cur_stack_boundary as isize));
                                     for _ in 0..num_args {
                                         let argument = self.store.read_take_ownership(cur_frame.expr_values.pop_front().unwrap());
                                         self.store.stack.push(argument);
+                                    }
                                     // Determine the monomorph index of the function we're calling
                                     let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
                                     let (type_id, monomorph_index) = mono_data.expr_info[expr.type_index as usize].variant.as_procedure();
                                     // Push the new frame and reserve its stack size
                                     let new_frame = Frame::new(heap, expr.procedure, type_id, monomorph_index);
                                     let new_stack_size = new_frame.max_stack_size;
                                     self.frames.push(new_frame);
                                     self.store.cur_stack_boundary = new_stack_boundary;
                                     self.store.reserve_stack(new_stack_size);
                                     // To simplify the logic a little bit we will now
                                     // return and ask our caller to call us again
                                     return Ok(EvalContinuation::Stepping);
+                                }
+                            }
                         },
                         Expression::Variable(expr) => {
                             let variable = &heap[expr.declaration.unwrap()];
                             let ref_value = if expr.used_as_binding_target {
                                 Value::Binding(variable.unique_id_in_scope as StackPos)
                             } else {
                                 Value::Ref(ValueId::Stack(variable.unique_id_in_scope as StackPos))
                             };
                             cur_frame.expr_values.push_back(ref_value);
+                        }
+                    }
+                }
+            }
+        }
         debug_log!("Frame [{:?}] at {:?}", cur_frame.definition, cur_frame.position);
         if debug_enabled!() {
             debug_log!("Expression value stack (size = {}):", cur_frame.expr_values.len());
             for (_stack_idx, _stack_val) in cur_frame.expr_values.iter().enumerate() {
                 debug_log!("  [{:03}] {:?}", _stack_idx, _stack_val);
+            }
             debug_log!("Stack (size = {}):", self.store.stack.len());
             for (_stack_idx, _stack_val) in self.store.stack.iter().enumerate() {
                 debug_log!("  [{:03}] {:?}", _stack_idx, _stack_val);
+            }
             debug_log!("Heap:");
             for (_heap_idx, _heap_region) in self.store.heap_regions.iter().enumerate() {
                 let _is_free = self.store.free_regions.iter().any(|idx| *idx as usize == _heap_idx);
                 debug_log!("  [{:03}] in_use: {}, len: {}, vals: {:?}", _heap_idx, !_is_free, _heap_region.values.len(), &_heap_region.values);
+            }
+        }
         // No (more) expressions to evaluate. So evaluate statement (that may
         // depend on the result on the last evaluated expression(s))
         let stmt = &heap[cur_frame.position];
         let return_value = match stmt {
             Statement::Block(stmt) => {
                 debug_assert!(stmt.statements.is_empty() || stmt.next == stmt.statements[0]);
                 cur_frame.position = stmt.next;
                 Ok(EvalContinuation::Stepping)
             },
             Statement::EndBlock(stmt) => {
                 let block = &heap[stmt.start_block];
                 let scope = &heap[block.scope];
                 self.store.clear_stack(scope.first_unique_id_in_scope as usize);
                 cur_frame.position = stmt.next;
                 Ok(EvalContinuation::Stepping)
             },
             Statement::Local(stmt) => {
                 match stmt {
                     LocalStatement::Memory(stmt) => {
                         dbg_code!({
                             let variable = &heap[stmt.variable];
                             debug_assert!(match self.store.read_ref(ValueId::Stack(variable.unique_id_in_scope as u32)) {
                                 Value::Unassigned => false,
                                 _ => true,
                             });
                         });
                         cur_frame.position = stmt.next;
                         Ok(EvalContinuation::Stepping)
                     },
                     LocalStatement::Channel(stmt) => {
                         // Need to create a new channel by requesting it from
                         // the runtime.
                         match ctx.created_channel() {
                             None => {
                                 // No channel is pending. So request one
                                     Ok(EvalContinuation::NewChannel)
                             },
                             Some((put_port, get_port)) => {
                                 self.store.write(ValueId::Stack(heap[stmt.from].unique_id_in_scope as u32), put_port);
                                 self.store.write(ValueId::Stack(heap[stmt.to].unique_id_in_scope as u32), get_port);
                                 cur_frame.position = stmt.next;
                                 Ok(EvalContinuation::Stepping)
+                            }
+                        }
+                    }
+                }
             },
             Statement::Labeled(stmt) => {
                 cur_frame.position = stmt.body;
                 Ok(EvalContinuation::Stepping)
             },
             Statement::If(stmt) => {
                 debug_assert_eq!(cur_frame.expr_values.len(), 1, "expected one expr value for if statement");
                 let test_value = cur_frame.expr_values.pop_back().unwrap();
                 let test_value = self.store.maybe_read_ref(&test_value).as_bool();
                 if test_value {
                     cur_frame.position = stmt.true_case.body;
                 } else if let Some(false_body) = stmt.false_case {
                     cur_frame.position = false_body.body;
                 } else {
                     // Not true, and no false body
                     cur_frame.position = stmt.end_if.upcast();
+                }
                 Ok(EvalContinuation::Stepping)
             },
             Statement::EndIf(stmt) => {
                 cur_frame.position = stmt.next;
                 let if_stmt = &heap[stmt.start_if];
                 debug_assert_eq!(
                     heap[if_stmt.true_case.scope].first_unique_id_in_scope,
                     heap[if_stmt.false_case.unwrap_or(if_stmt.true_case).scope].first_unique_id_in_scope,
                 );
                 let scope = &heap[if_stmt.true_case.scope];
                 self.store.clear_stack(scope.first_unique_id_in_scope as usize);
                 Ok(EvalContinuation::Stepping)
             },
             Statement::While(stmt) => {
                 debug_assert_eq!(cur_frame.expr_values.len(), 1, "expected one expr value for while statement");
                 let test_value = cur_frame.expr_values.pop_back().unwrap();
                 let test_value = self.store.maybe_read_ref(&test_value).as_bool();
                 if test_value {
                     cur_frame.position = stmt.body;
                 } else {
                     cur_frame.position = stmt.end_while.upcast();
+                }
                 Ok(EvalContinuation::Stepping)
             },
             Statement::EndWhile(stmt) => {
                 cur_frame.position = stmt.next;
                 let start_while = &heap[stmt.start_while];
                 let scope = &heap[start_while.scope];
                 self.store.clear_stack(scope.first_unique_id_in_scope as usize);
                 Ok(EvalContinuation::Stepping)
             },
             Statement::Break(stmt) => {
                 cur_frame.position = stmt.target.upcast();
                 Ok(EvalContinuation::Stepping)
             },
             Statement::Continue(stmt) => {
                 cur_frame.position = stmt.target.upcast();
                 Ok(EvalContinuation::Stepping)
             },
             Statement::Synchronous(stmt) => {
                 cur_frame.position = stmt.body;
                 Ok(EvalContinuation::SyncBlockStart)
             },
             Statement::EndSynchronous(stmt) => {
                 cur_frame.position = stmt.next;
                 let start_synchronous = &heap[stmt.start_sync];
                 let scope = &heap[start_synchronous.scope];
                 self.store.clear_stack(scope.first_unique_id_in_scope as usize);
                 Ok(EvalContinuation::SyncBlockEnd)
             },
             Statement::Fork(stmt) => {
                 if stmt.right_body.is_none() {
                     // No reason to fork
                     cur_frame.position = stmt.left_body;
                 } else {
                     // Need to fork
                     if let Some(go_left) = ctx.performed_fork() {
                         // Runtime has created a fork
                         if go_left {
                             cur_frame.position = stmt.left_body;
                         } else {
                             cur_frame.position = stmt.right_body.unwrap();
+                        }
                     } else {
                         // Request the runtime to create a fork of the current
                         // branch
                         return Ok(EvalContinuation::NewFork);
+                    }
+                }
                 Ok(EvalContinuation::Stepping)
             },
             Statement::EndFork(stmt) => {
                 cur_frame.position = stmt.next;
                 Ok(EvalContinuation::Stepping)
             },
             Statement::Select(stmt) => {
                 // This is a trampoline for the statements that were placed by
                 // the AST transformation pass
                 cur_frame.position = stmt.next;
                 Ok(EvalContinuation::Stepping)
             },
             Statement::EndSelect(stmt) => {
                 cur_frame.position = stmt.next;
                 let start_select = &heap[stmt.start_select];
                 if let Some(select_case) = start_select.cases.first() {
                     let scope = &heap[select_case.scope];
                     self.store.clear_stack(scope.first_unique_id_in_scope as usize);
+                }
                 Ok(EvalContinuation::Stepping)
             },
             Statement::Return(_stmt) => {
                 debug_assert_eq!(cur_frame.expr_values.len(), 1, "expected one expr value for return statement");
                 // The preceding frame has executed a call, so is expecting the
                 // return expression on its expression value stack. Note that
                 // we may be returning a reference to something on our stack,
                 // so we need to read that value and clone it.
                 let return_value = cur_frame.expr_values.pop_back().unwrap();
                 let return_value = match return_value {
                     Value::Ref(value_id) => self.store.read_copy(value_id),
                     _ => return_value,
                 };
                 // Pre-emptively pop our stack frame
                 self.frames.pop();
                 // Clean up our section of the stack
                 self.store.clear_stack(0);
                 self.store.stack.truncate(self.store.cur_stack_boundary + 1);
                 let prev_stack_idx = self.store.stack.pop().unwrap().as_stack_boundary();
                 // TODO: Temporary hack for testing, remove at some point
                 if self.frames.is_empty() {
                     debug_assert!(prev_stack_idx == -1);
                     debug_assert!(self.store.stack.len() == 0);
                     self.store.stack.push(return_value);
                     return Ok(EvalContinuation::ComponentTerminated);
+                }
                 debug_assert!(prev_stack_idx >= 0);
                 // Return to original state of stack frame
                 self.store.cur_stack_boundary = prev_stack_idx as usize;
                 let cur_frame = self.frames.last_mut().unwrap();
                 cur_frame.expr_values.push_back(return_value);
                 // We just returned to the previous frame, which might be in
                 // the middle of evaluating expressions for a particular
                 // statement. So we don't want to enter the code below.
                 return Ok(EvalContinuation::Stepping);
             },
             Statement::Goto(stmt) => {
                 cur_frame.position = stmt.target.upcast();
                 Ok(EvalContinuation::Stepping)
             },
             Statement::New(stmt) => {
                 let call_expr = &heap[stmt.expression];
                 debug_assert_eq!(
                     cur_frame.expr_values.len(), heap[call_expr.procedure].parameters.len(),
                     "mismatch in expr stack size and number of arguments for new statement"
                 );
                 let mono_data = &heap[cur_frame.definition].monomorphs[cur_frame.monomorph_index];
                 let type_id = mono_data.expr_info[call_expr.type_index as usize].variant.as_procedure().0;
                 // Note that due to expression value evaluation they exist in
                 // reverse order on the stack.
                 // TODO: Revise this code, keep it as is to be compatible with current runtime
                 let mut args = Vec::new();
                 while let Some(value) = cur_frame.expr_values.pop_front() {
                     args.push(value);
+                }
                 // Construct argument group, thereby copying heap regions
                 let argument_group = ValueGroup::from_store(&self.store, &args);
                 // Clear any heap regions
                 for arg in &args {
                     self.store.drop_value(arg.get_heap_pos());
+                }
                 cur_frame.position = stmt.next;
                 Ok(EvalContinuation::NewComponent(call_expr.procedure, type_id, argument_group))
             },
             Statement::Expression(stmt) => {
                 // The expression has just been completely evaluated. Some
                 // values might have remained on the expression value stack.
                 // cur_frame.expr_values.clear(); PROPER CLEARING
                 cur_frame.position = stmt.next;
                 Ok(EvalContinuation::Stepping)
             },
         };
         assert!(
             cur_frame.expr_values.is_empty(),
             "This is a debugging assertion that will fail if you perform expressions without \
             assigning to anything. This should be completely valid, and this assertion should be \
             replaced by something that clears the expression values if needed, but I'll keep this \
             in for now for debugging purposes."
         );
         // If the next statement requires evaluating expressions then we push
         // these onto the expression stack. This way we will evaluate this
         // stack in the next loop, then evaluate the statement using the result
         // from the expression evaluation.
         if !cur_frame.position.is_invalid() {
             let stmt = &heap[cur_frame.position];
             match stmt {
                 Statement::Local(stmt) => {
                     if let LocalStatement::Memory(stmt) = stmt {
                         // Setup as unassigned, when we execute the memory
                         // statement (after evaluating expression), it should no
                         // longer be `Unassigned`.
                         let variable = &heap[stmt.variable];
                         self.store.write(ValueId::Stack(variable.unique_id_in_scope as u32), Value::Unassigned);
                         cur_frame.prepare_single_expression(heap, stmt.initial_expr.upcast());
+                    }
                 },
                 Statement::If(stmt) => cur_frame.prepare_single_expression(heap, stmt.test),
                 Statement::While(stmt) => cur_frame.prepare_single_expression(heap, stmt.test),
                 Statement::Return(stmt) => {
                     debug_assert_eq!(stmt.expressions.len(), 1); // TODO: @ReturnValues
                     cur_frame.prepare_single_expression(heap, stmt.expressions[0]);
                 },
                 Statement::New(stmt) => {
                     // Note that we will end up not evaluating the call itself.
                     // Rather we will evaluate its expressions and then
                     // instantiate the component upon reaching the "new" stmt.
                     let call_expr = &heap[stmt.expression];
                     cur_frame.prepare_multiple_expressions(heap, &call_expr.arguments);
                 },
                 Statement::Expression(stmt) => {
                     cur_frame.prepare_single_expression(heap, stmt.expression);
+                }
                 _ => {},
+            }
+        }
         return_value
+    }
     /// Constructs an error at the current expression that lives at the top of
     /// the expression stack. Falls back to constructing an error at the current
     /// statement if there is no expression.
     pub(crate) fn new_error_at_expr(&self, modules: &[Module], heap: &Heap, error_message: String) -> EvalError {
         let last_frame = self.frames.last().unwrap();
         for instruction in last_frame.expr_stack.iter().rev() {
             if let ExprInstruction::EvalExpr(expression_id) = instruction {
                 return EvalError::new_error_at_expr(
                     self, modules, heap, *expression_id, error_message
                 );
+            }
+        }
         // If here then expression stack was empty (cannot have just rotate
         // instructions)
         panic!("attempted to construct evaluation error without any expressions to evaluate in frame");
+    }
+}
@@ \ No newline at end of file @@

src/protocol/mod.rs

➞

Show inline comments

 mod arena;
 pub(crate) mod eval;
 pub(crate) mod input_source;
 mod parser;
 #[cfg(test)] mod tests;
 pub(crate) mod ast;
 pub(crate) mod ast_writer;
 mod token_writer;
 use std::sync::Mutex;
 use crate::collections::{StringPool, StringRef};
 pub use crate::protocol::ast::*;
 use crate::protocol::eval::*;
 use crate::protocol::input_source::*;
 use crate::protocol::parser::*;
 use crate::protocol::type_table::*;
 pub use parser::type_table::TypeId;
 /// A protocol description module
 pub struct Module {
     pub(crate) source: InputSource,
     pub(crate) root_id: RootId,
     pub(crate) name: Option<StringRef<'static>>,
+}
 /// Description of a protocol object, used to configure new connectors.
 #[repr(C)]
 pub struct ProtocolDescription {
     pub(crate) modules: Vec<Module>,
     pub(crate) heap: Heap,
     pub(crate) types: TypeTable,
     pub(crate) pool: Mutex<StringPool>,
+}
 #[derive(Debug, Clone)]
 pub(crate) struct ComponentState {
     pub(crate) prompt: Prompt,
+}
 #[derive(Debug)]
 pub enum ComponentCreationError {
     ModuleDoesntExist,
     DefinitionDoesntExist,
     DefinitionNotComponent,
     InvalidNumArguments,
     InvalidArgumentType(usize),
     UnownedPort,
     InSync,
+}
 impl ProtocolDescription {
     pub fn parse(buffer: &[u8]) -> Result<Self, String> {
         let source = InputSource::new(String::new(), Vec::from(buffer));
         let mut parser = Parser::new(None)?;
         parser.feed(source).expect("failed to feed source");
         if let Err(err) = parser.parse() {
             println!("ERROR:\n{}", err);
             return Err(format!("{}", err))
+        }
         let modules: Vec<Module> = parser.modules.into_iter()
             .map(|module| Module{
                 source: module.source,
                 root_id: module.root_id,
                 name: module.name.map(|(_, name)| name)
             })
             .collect();
         return Ok(ProtocolDescription {
             modules,
             heap: parser.heap,
             types: parser.type_table,
             pool: Mutex::new(parser.string_pool),
         });
+    }
     pub(crate) fn new_component(
         &self, module_name: &[u8], identifier: &[u8], arguments: ValueGroup
     ) -> Result<Prompt, ComponentCreationError> {
         // Find the module in which the definition can be found
         let module_root = self.lookup_module_root(module_name);
         if module_root.is_none() {
             return Err(ComponentCreationError::ModuleDoesntExist);
+        }
         let module_root = module_root.unwrap();
         let root = &self.heap[module_root];
         let definition_id = root.get_definition_by_ident(&self.heap, identifier);
         if definition_id.is_none() {
             return Err(ComponentCreationError::DefinitionDoesntExist);
+        }
         let definition_id = definition_id.unwrap();
         let ast_definition = &self.heap[definition_id];
         if !ast_definition.is_procedure() {
             return Err(ComponentCreationError::DefinitionNotComponent);
+        }
         // Make sure that the types of the provided value group matches that of
         // the expected types.
         let ast_definition = ast_definition.as_procedure();
         if !ast_definition.poly_vars.is_empty() || ast_definition.kind == ProcedureKind::Function {
             return Err(ComponentCreationError::DefinitionNotComponent);
+        }
         // - check number of arguments by retrieving the one instantiated
         //   monomorph
         let concrete_type = ConcreteType{ parts: vec![ConcreteTypePart::Component(ast_definition.this, 0)] };
         let procedure_type_id = self.types.get_monomorph_type_id(&definition_id, &concrete_type.parts).unwrap();
         let procedure_monomorph_index = self.types.get_monomorph(procedure_type_id).variant.as_procedure().monomorph_index;
         let monomorph_info = &ast_definition.monomorphs[procedure_monomorph_index as usize];
         if monomorph_info.argument_types.len() != arguments.values.len() {
             return Err(ComponentCreationError::InvalidNumArguments);
+        }
         // - for each argument try to make sure the types match
         for arg_idx in 0..arguments.values.len() {
             let expected_type_id = monomorph_info.argument_types[arg_idx];
             let expected_type = &self.types.get_monomorph(expected_type_id).concrete_type;
             let provided_value = &arguments.values[arg_idx];
             if !self.verify_same_type(expected_type, 0, &arguments, provided_value) {
                 return Err(ComponentCreationError::InvalidArgumentType(arg_idx));
+            }
+        }
         // By now we're sure that all of the arguments are correct. So create
         // the connector.
         return Ok(Prompt::new(&self.types, &self.heap, ast_definition.this, procedure_type_id, arguments));
+    }
     /// A somewhat temporary method. Can be used by components to lookup type
     /// definitions by their name (to have their implementation somewhat
     /// resistant to changes in the standard library)
     pub(crate) fn find_type<'a>(&'a self, module_name: &[u8], type_name: &[u8]) -> Option<TypeInspector<'a>> {
         // Lookup type definition in module
         let root_id = self.lookup_module_root(module_name)?;
         let module = &self.heap[root_id];
         let definition_id = module.get_definition_by_ident(&self.heap, type_name)?;
         let definition = &self.heap[definition_id];
         // Make sure type is not polymorphic and is not a procedure
         if !definition.poly_vars().is_empty() {
             return None;
+        }
         if definition.is_procedure() {
             return None;
+        }
         // Lookup type in type table
         let type_parts = [ConcreteTypePart::Instance(definition_id, 0)];
         let type_id = self.types.get_monomorph_type_id(&definition_id, &type_parts)
             .expect("type ID for non-polymorphic type");
         let type_monomorph = self.types.get_monomorph(type_id);
         return Some(TypeInspector{
             heap: definition,
             type_table: type_monomorph
         });
+    }
     /// Again a somewhat temporary method. Can be used by components to look up
     /// the definition of a particular procedure. Intended use is to find the
     /// DefinitionId/TypeId of builtin components.
     pub(crate) fn find_procedure(&self, module_name: &[u8], proc_name: &[u8]) -> Option<(ProcedureDefinitionId, TypeId)> {
         // Lookup type definition in module
         let root_id = self.lookup_module_root(module_name)?;
         let module = &self.heap[root_id];
         let definition_id = module.get_definition_by_ident(&self.heap, proc_name)?;
         let definition = &self.heap[definition_id];
         // Make sure the procedure is not polymorphic
         if !definition.poly_vars().is_empty() {
             return None;
+        }
         if !definition.is_procedure() {
             return None;
+        }
         // Lookup in type table
         let definition = definition.as_procedure();
         let type_parts = [ConcreteTypePart::Component(definition.this, 0)];
         let type_id = self.types.get_monomorph_type_id(&definition.this.upcast(), &type_parts)
             .expect("type ID for non-polymorphic procedure");
         return Some((definition.this, type_id));
+    }
     fn lookup_module_root(&self, module_name: &[u8]) -> Option<RootId> {
         for module in self.modules.iter() {
             match &module.name {
                 Some(name) => if name.as_bytes() == module_name {
                     return Some(module.root_id);
                 },
                 None => if module_name.is_empty() {
                     return Some(module.root_id);
+                }
+            }
+        }
         return None;
+    }
     fn verify_same_type(&self, expected: &ConcreteType, expected_idx: usize, arguments: &ValueGroup, argument: &Value) -> bool {
         use ConcreteTypePart as CTP;
         match &expected.parts[expected_idx] {
             CTP::Void | CTP::Message | CTP::Slice | CTP::Pointer | CTP::Function(_, _) | CTP::Component(_, _) => unreachable!(),
             CTP::Bool => if let Value::Bool(_) = argument { true } else { false },
             CTP::UInt8 => if let Value::UInt8(_) = argument { true } else { false },
             CTP::UInt16 => if let Value::UInt16(_) = argument { true } else { false },
             CTP::UInt32 => if let Value::UInt32(_) = argument { true } else { false },
             CTP::UInt64 => if let Value::UInt64(_) = argument { true } else { false },
             CTP::SInt8 => if let Value::SInt8(_) = argument { true } else { false },
             CTP::SInt16 => if let Value::SInt16(_) = argument { true } else { false },
             CTP::SInt32 => if let Value::SInt32(_) = argument { true } else { false },
             CTP::SInt64 => if let Value::SInt64(_) = argument { true } else { false },
             CTP::Character => if let Value::Char(_) = argument { true } else { false },
             CTP::String => {
                 // Match outer string type and embedded character types
                 if let Value::String(heap_pos) = argument {
                     for element in &arguments.regions[*heap_pos as usize] {
                         if let Value::Char(_) = element {} else {
                             return false;
+                        }
+                    }
                 } else {
                     return false;
+                }
                 return true;
             },
             CTP::Array => {
                 if let Value::Array(heap_pos) = argument {
                     let heap_pos = *heap_pos;
                     for element in &arguments.regions[heap_pos as usize] {
                         if !self.verify_same_type(expected, expected_idx + 1, arguments, element) {
                             return false;
+                        }
+                    }
                     return true;
                 } else {
                     return false;
+                }
             },
             CTP::Input => if let Value::Input(_) = argument { true } else { false },
             CTP::Output => if let Value::Output(_) = argument { true } else { false },
             CTP::Tuple(_) => todo!("implement full type checking on user-supplied arguments"),
             CTP::Instance(definition_id, _num_embedded) => {
                 let definition = self.types.get_base_definition(definition_id).unwrap();
                 match &definition.definition {
                     DefinedTypeVariant::Enum(definition) => {
                         if let Value::Enum(variant_value) = argument {
                             let is_valid = definition.variants.iter()
                                 .any(|v| v.value == *variant_value);
                             return is_valid;
+                        }
                     },
                     _ => todo!("implement full type checking on user-supplied arguments"),
+                }
                 return false;
             },
+        }
+    }
+}
 pub trait RunContext {
     fn performed_put(&mut self, port: PortId) -> bool;
     fn performed_get(&mut self, port: PortId) -> Option<ValueGroup>; // None if still waiting on message
     fn fires(&mut self, port: PortId) -> Option<Value>; // None if not yet branched
     fn performed_fork(&mut self) -> Option<bool>; // None if not yet forked
     fn created_channel(&mut self) -> Option<(Value, Value)>; // None if not yet prepared
     fn performed_select_wait(&mut self) -> Option<u32>; // None if not yet notified runtime of select blocker
+}
 pub struct ProtocolDescriptionBuilder {
     parser: Parser,
+}
 impl ProtocolDescriptionBuilder {
     pub fn new(std_lib_dir: Option<String>) -> Result<Self, String> {
         let mut parser = Parser::new(std_lib_dir)?;
         return Ok(Self{ parser })
+    }
     pub fn add(&mut self, filename: String, buffer: Vec<u8>) -> Result<(), ParseError> {
         let input = InputSource::new(filename, buffer);
         self.parser.feed(input)?;
         return Ok(())
+    }
     pub fn compile(mut self) -> Result<ProtocolDescription, ParseError> {
         self.parser.parse()?;
         let modules: Vec<Module> = self.parser.modules.into_iter()
             .map(|module| Module{
                 source: module.source,
                 root_id: module.root_id,
                 name: module.name.map(|(_, name)| name)
             })
             .collect();
         return Ok(ProtocolDescription {
             modules,
             heap: self.parser.heap,
             types: self.parser.type_table,
             pool: Mutex::new(self.parser.string_pool),
         });
+    }
+}
 pub struct TypeInspector<'a> {
     heap: &'a Definition,
     type_table: &'a MonoType,
+}
 impl<'a> TypeInspector<'a> {
     pub fn as_union(&'a self) -> UnionTypeInspector<'a> {
         let heap = self.heap.as_union();
         let type_table = self.type_table.variant.as_union();
         return UnionTypeInspector{ heap, type_table };
+    }
     pub fn as_struct(&'a self) -> StructTypeInspector<'a> {
         let heap = self.heap.as_struct();
         let type_table = self.type_table.variant.as_struct();
         return StructTypeInspector{ heap, type_table };
+    }
+}
 pub struct UnionTypeInspector<'a> {
     heap: &'a UnionDefinition,
     type_table: &'a UnionMonomorph,
+}
 impl UnionTypeInspector<'_> {
     /// Retrieves union variant tag value.
     pub fn get_variant_tag_value(&self, variant_name: &[u8]) -> Option<i64> {
         let variant_index = self.heap.variants.iter()
             .position(|v| v.identifier.value.as_bytes() == variant_name)?;
         return Some(variant_index as i64);
+    }
+}
 pub struct StructTypeInspector<'a> {
     heap: &'a StructDefinition,
     type_table: &'a StructMonomorph,
+}
 impl StructTypeInspector<'_> {
     /// Retrieves number of struct fields
     pub fn get_num_struct_fields(&self) -> usize {
         return self.heap.fields.len();
+    }
     /// Retrieves struct field index
     pub fn get_struct_field_index(&self, field_name: &[u8]) -> Option<usize> {
         let field_index = self.heap.fields.iter()
             .position(|v| v.field.value.as_bytes() == field_name)?;
         return Some(field_index);
+    }
+}
@@ \ No newline at end of file @@

src/protocol/parser/pass_definitions.rs

➞

Show inline comments

 use crate::protocol::ast::*;
 use super::symbol_table::*;
 use super::{Module, ModuleCompilationPhase, PassCtx};
 use super::tokens::*;
 use super::token_parsing::*;
 use super::pass_definitions_types::*;
 use crate::protocol::input_source::{InputSource, InputPosition, InputSpan, ParseError};
 use crate::collections::*;
 /// Parses all the tokenized definitions into actual AST nodes.
 pub(crate) struct PassDefinitions {
     // State associated with the definition currently being processed
     cur_definition: DefinitionId,
     // Itty bitty parsing machines
     type_parser: ParserTypeParser,
     // Temporary buffers of various kinds
     buffer: String,
     struct_fields: ScopedBuffer<StructFieldDefinition>,
     enum_variants: ScopedBuffer<EnumVariantDefinition>,
     union_variants: ScopedBuffer<UnionVariantDefinition>,
     variables: ScopedBuffer<VariableId>,
     expressions: ScopedBuffer<ExpressionId>,
     statements: ScopedBuffer<StatementId>,
     parser_types: ScopedBuffer<ParserType>,
+}
 impl PassDefinitions {
     pub(crate) fn new() -> Self {
         Self{
             cur_definition: DefinitionId::new_invalid(),
             type_parser: ParserTypeParser::new(),
             buffer: String::with_capacity(128),
             struct_fields: ScopedBuffer::with_capacity(128),
             enum_variants: ScopedBuffer::with_capacity(128),
             union_variants: ScopedBuffer::with_capacity(128),
             variables: ScopedBuffer::with_capacity(128),
             expressions: ScopedBuffer::with_capacity(128),
             statements: ScopedBuffer::with_capacity(128),
             parser_types: ScopedBuffer::with_capacity(128),
+        }
+    }
     pub(crate) fn parse(&mut self, modules: &mut [Module], module_idx: usize, ctx: &mut PassCtx) -> Result<(), ParseError> {
         let module = &modules[module_idx];
         debug_assert_eq!(module.phase, ModuleCompilationPhase::ImportsResolved);
         // We iterate through the entire document. If we find a marker that has
         // been handled then we skip over it. It is important that we properly
         // parse all other tokens in the document to ensure that we throw the
         // correct kind of errors.
         let num_tokens = module.tokens.tokens.len() as u32;
         let num_markers = module.tokens.markers.len();
         let mut marker_index = 0;
         let mut first_token_index = 0;
         while first_token_index < num_tokens {
             // Seek ahead to the next marker that was already handled.
             let mut last_token_index = num_tokens;
             let mut new_first_token_index = num_tokens;
             while marker_index < num_markers {
                 let marker = &module.tokens.markers[marker_index];
                 marker_index += 1;
                 if marker.handled {
                     last_token_index = marker.first_token;
                     new_first_token_index = marker.last_token;
                     break;
+                }
+            }
             self.visit_token_range(modules, module_idx, ctx, first_token_index, last_token_index)?;
             first_token_index = new_first_token_index;
+        }
         modules[module_idx].phase = ModuleCompilationPhase::DefinitionsParsed;
         Ok(())
+    }
     fn visit_token_range(
         &mut self, modules: &[Module], module_idx: usize, ctx: &mut PassCtx,
         token_range_begin: u32, token_range_end: u32,
     ) -> Result<(), ParseError> {
         let module = &modules[module_idx];
         // Detect which definition we're parsing
         let mut iter = module.tokens.iter_range(token_range_begin, Some(token_range_end));
         loop {
             let next = iter.next();
             if next.is_none() {
                 return Ok(())
+            }
             // Token was not None, so peek_ident returns None if not an ident
             let ident = peek_ident(&module.source, &mut iter);
             match ident {
                 Some(KW_STRUCT) => self.visit_struct_definition(module, &mut iter, ctx)?,
                 Some(KW_ENUM) => self.visit_enum_definition(module, &mut iter, ctx)?,
                 Some(KW_UNION) => self.visit_union_definition(module, &mut iter, ctx)?,
                 Some(KW_FUNCTION) => self.visit_function_definition(module, &mut iter, ctx)?,
                 Some(KW_COMPONENT) => self.visit_component_definition(module, &mut iter, ctx)?,
                 _ => return Err(ParseError::new_error_str_at_pos(
                     &module.source, iter.last_valid_pos(),
                     "unexpected symbol, expected a keyword marking the start of a definition"
                 )),
+            }
+        }
+    }
     fn visit_struct_definition(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<(), ParseError> {
         consume_exact_ident(&module.source, iter, KW_STRUCT)?;
         let (ident_text, _) = consume_ident(&module.source, iter)?;
         // Retrieve preallocated DefinitionId
         let module_scope = SymbolScope::Module(module.root_id);
         let definition_id = ctx.symbols.get_symbol_by_name_defined_in_scope(module_scope, ident_text)
             .unwrap().variant.as_definition().definition_id;
         self.cur_definition = definition_id;
         // Parse struct definition
         consume_polymorphic_vars_spilled(&module.source, iter, ctx)?;
         let mut fields_section = self.struct_fields.start_section();
         consume_comma_separated(
             TokenKind::OpenCurly, TokenKind::CloseCurly, &module.source, iter, ctx,
             |source, iter, ctx| {
                 let poly_vars = ctx.heap[definition_id].poly_vars();
                 let start_pos = iter.last_valid_pos();
                 let parser_type = self.type_parser.consume_parser_type(
                     iter, &ctx.heap, source, &ctx.symbols, poly_vars, definition_id,
                     module_scope, false, false, None
                 )?;
                 let field = consume_ident_interned(source, iter, ctx)?;
                 Ok(StructFieldDefinition{
                     span: InputSpan::from_positions(start_pos, field.span.end),
                     field, parser_type
                 })
             },
             &mut fields_section, "a struct field", "a list of struct fields", None
         )?;
         // Transfer to preallocated definition
         let struct_def = ctx.heap[definition_id].as_struct_mut();
         struct_def.fields = fields_section.into_vec();
         Ok(())
+    }
     fn visit_enum_definition(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<(), ParseError> {
         consume_exact_ident(&module.source, iter, KW_ENUM)?;
         let (ident_text, _) = consume_ident(&module.source, iter)?;
         // Retrieve preallocated DefinitionId
         let module_scope = SymbolScope::Module(module.root_id);
         let definition_id = ctx.symbols.get_symbol_by_name_defined_in_scope(module_scope, ident_text)
             .unwrap().variant.as_definition().definition_id;
         self.cur_definition = definition_id;
         // Parse enum definition
         consume_polymorphic_vars_spilled(&module.source, iter, ctx)?;
         let mut enum_section = self.enum_variants.start_section();
         consume_comma_separated(
             TokenKind::OpenCurly, TokenKind::CloseCurly, &module.source, iter, ctx,
             |source, iter, ctx| {
                 let identifier = consume_ident_interned(source, iter, ctx)?;
                 let value = if iter.next() == Some(TokenKind::Equal) {
                     iter.consume();
                     let (variant_number, _) = consume_integer_literal(source, iter, &mut self.buffer)?;
                     EnumVariantValue::Integer(variant_number as i64) // TODO: @int
                 } else {
                     EnumVariantValue::None
                 };
                 Ok(EnumVariantDefinition{ identifier, value })
             },
             &mut enum_section, "an enum variant", "a list of enum variants", None
         )?;
         // Transfer to definition
         let enum_def = ctx.heap[definition_id].as_enum_mut();
         enum_def.variants = enum_section.into_vec();
         Ok(())
+    }
     fn visit_union_definition(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<(), ParseError> {
         consume_exact_ident(&module.source, iter, KW_UNION)?;
         let (ident_text, _) = consume_ident(&module.source, iter)?;
         // Retrieve preallocated DefinitionId
         let module_scope = SymbolScope::Module(module.root_id);
         let definition_id = ctx.symbols.get_symbol_by_name_defined_in_scope(module_scope, ident_text)
             .unwrap().variant.as_definition().definition_id;
         self.cur_definition = definition_id;
         // Parse union definition
         consume_polymorphic_vars_spilled(&module.source, iter, ctx)?;
         let mut variants_section = self.union_variants.start_section();
         consume_comma_separated(
             TokenKind::OpenCurly, TokenKind::CloseCurly, &module.source, iter, ctx,
             |source, iter, ctx| {
                 let identifier = consume_ident_interned(source, iter, ctx)?;
                 let mut close_pos = identifier.span.end;
                 let mut types_section = self.parser_types.start_section();
                 let has_embedded = maybe_consume_comma_separated(
                     TokenKind::OpenParen, TokenKind::CloseParen, source, iter, ctx,
                     |source, iter, ctx| {
                         let poly_vars = ctx.heap[definition_id].poly_vars();
                         self.type_parser.consume_parser_type(
                             iter, &ctx.heap, source, &ctx.symbols, poly_vars, definition_id,
                             module_scope, false, false, None
+                        )
                     },
                     &mut types_section, "an embedded type", Some(&mut close_pos)
                 )?;
                 let value = if has_embedded {
                     types_section.into_vec()
                 } else {
                     types_section.forget();
                     Vec::new()
                 };
                 Ok(UnionVariantDefinition{
                     span: InputSpan::from_positions(identifier.span.begin, close_pos),
                     identifier,
                     value
                 })
             },
             &mut variants_section, "a union variant", "a list of union variants", None
         )?;
         // Transfer to AST
         let union_def = ctx.heap[definition_id].as_union_mut();
         union_def.variants = variants_section.into_vec();
         Ok(())
+    }
     fn visit_function_definition(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<(), ParseError> {
         // Retrieve function name
         consume_exact_ident(&module.source, iter, KW_FUNCTION)?;
         let (ident_text, _) = consume_ident(&module.source, iter)?;
         // Retrieve preallocated DefinitionId
         let module_scope = SymbolScope::Module(module.root_id);
         let definition_id = ctx.symbols.get_symbol_by_name_defined_in_scope(module_scope, ident_text)
             .unwrap().variant.as_definition().definition_id;
         self.cur_definition = definition_id;
         let allow_compiler_types = module.is_compiler_file;
         consume_polymorphic_vars_spilled(&module.source, iter, ctx)?;
         // Parse function's argument list
         let mut parameter_section = self.variables.start_section();
         consume_parameter_list(
             &mut self.type_parser, &module.source, iter, ctx, &mut parameter_section,
             module_scope, definition_id, allow_compiler_types
         )?;
         let parameters = parameter_section.into_vec();
         // Consume return types
         consume_token(&module.source, iter, TokenKind::ArrowRight)?;
         let poly_vars = ctx.heap[definition_id].poly_vars();
         let parser_type = self.type_parser.consume_parser_type(
             iter, &ctx.heap, &module.source, &ctx.symbols, poly_vars, definition_id,
             module_scope, false, allow_compiler_types, None
         )?;
         // Consume body
         let (body_id, source) = self.consume_procedure_body(module, iter, ctx, definition_id, ProcedureKind::Function)?;
         let scope_id = ctx.heap.alloc_scope(|this| Scope::new(this, ScopeAssociation::Definition(definition_id)));
         // Assign everything in the preallocated AST node
         let function = ctx.heap[definition_id].as_procedure_mut();
         function.source = source;
         function.return_type = Some(parser_type);
         function.parameters = parameters;
         function.scope = scope_id;
         function.body = body_id;
         Ok(())
+    }
     fn visit_component_definition(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<(), ParseError> {
         // Consume component variant and name
         let (_component_text, _) = consume_any_ident(&module.source, iter)?;
         debug_assert!(_component_text == KW_COMPONENT);
         let (ident_text, _) = consume_ident(&module.source, iter)?;
         // Retrieve preallocated definition
         let module_scope = SymbolScope::Module(module.root_id);
         let definition_id = ctx.symbols.get_symbol_by_name_defined_in_scope(module_scope, ident_text)
             .unwrap().variant.as_definition().definition_id;
         self.cur_definition = definition_id;
         let allow_compiler_types = module.is_compiler_file;
         consume_polymorphic_vars_spilled(&module.source, iter, ctx)?;
         // Parse component's argument list
         let mut parameter_section = self.variables.start_section();
         consume_parameter_list(
             &mut self.type_parser, &module.source, iter, ctx, &mut parameter_section,
             module_scope, definition_id, allow_compiler_types
         )?;
         let parameters = parameter_section.into_vec();
         // Consume body
         let procedure_kind = ctx.heap[definition_id].as_procedure().kind;
         let (body_id, source) = self.consume_procedure_body(module, iter, ctx, definition_id, procedure_kind)?;
         let scope_id = ctx.heap.alloc_scope(|this| Scope::new(this, ScopeAssociation::Definition(definition_id)));
         // Assign everything in the AST node
         let component = ctx.heap[definition_id].as_procedure_mut();
         debug_assert!(component.return_type.is_none());
         component.source = source;
         component.parameters = parameters;
         component.scope = scope_id;
         component.body = body_id;
         Ok(())
+    }
     /// Consumes a procedure's body: either a user-defined procedure, which we
     /// parse as normal, or a builtin function, where we'll make sure we expect
     /// the particular builtin.
     ///
     /// We expect that the procedure's name is already stored in the
     /// preallocated AST node.
     fn consume_procedure_body(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx, definition_id: DefinitionId, kind: ProcedureKind
     ) -> Result<(BlockStatementId, ProcedureSource), ParseError> {
         if iter.next() == Some(TokenKind::OpenCurly) && iter.peek() == Some(TokenKind::Pragma) {
             // Consume the placeholder "{ #builtin }" tokens
             iter.consume(); // opening curly brace
             let (pragma, pragma_span) = consume_pragma(&module.source, iter)?;
             if pragma != b"#builtin" {
                 return Err(ParseError::new_error_str_at_span(
                     &module.source, pragma_span,
                     "expected a '#builtin' pragma, or a function body"
                 ));
+            }
             if iter.next() != Some(TokenKind::CloseCurly) {
                 // Just to keep the compiler writers in line ;)
                 panic!("compiler error: when using the #builtin pragma, wrap it in curly braces");
+            }
             iter.consume();
             // Retrieve module and procedure name
             assert!(module.name.is_some(), "compiler error: builtin procedure body in unnamed module");
             let (_, module_name) = module.name.as_ref().unwrap();
             let module_name = module_name.as_str();
             let definition = ctx.heap[definition_id].as_procedure();
             let procedure_name = definition.identifier.value.as_str();
             let source = match (module_name, procedure_name) {
                 ("std.global", "get") => ProcedureSource::FuncGet,
                 ("std.global", "put") => ProcedureSource::FuncPut,
                 ("std.global", "fires") => ProcedureSource::FuncFires,
                 ("std.global", "create") => ProcedureSource::FuncCreate,
                 ("std.global", "length") => ProcedureSource::FuncLength,
                 ("std.global", "assert") => ProcedureSource::FuncAssert,
                 ("std.global", "print") => ProcedureSource::FuncPrint,
                 ("std.random", "random_u32") => ProcedureSource::CompRandomU32,
                 ("std.internet", "tcp_client") => ProcedureSource::CompTcpClient,
                 ("std.internet", "tcp_listener") => ProcedureSource::CompTcpListener,
                 _ => panic!(
                     "compiler error: unknown builtin procedure '{}' in module '{}'",
                     procedure_name, module_name
                 ),
             };
             return Ok((BlockStatementId::new_invalid(), source));
         } else {
             let body_id = self.consume_block_statement(module, iter, ctx)?;
             let source = match kind {
                 ProcedureKind::Function =>
                     ProcedureSource::FuncUserDefined,
                 ProcedureKind::Component =>
                     ProcedureSource::CompUserDefined,
             };
             return Ok((body_id, source))
+        }
+    }
     /// Consumes a statement and returns a boolean indicating whether it was a
     /// block or not.
     fn consume_statement(&mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx) -> Result<StatementId, ParseError> {
         let next = iter.next().expect("consume_statement has a next token");
         if next == TokenKind::OpenCurly {
             let id = self.consume_block_statement(module, iter, ctx)?;
             return Ok(id.upcast());
         } else if next == TokenKind::Ident {
             let ident = peek_ident(&module.source, iter).unwrap();
             if ident == KW_STMT_IF {
                 // Consume if statement and place end-if statement directly
                 // after it.
                 let id = self.consume_if_statement(module, iter, ctx)?;
                 return Ok(id.upcast());
             } else if ident == KW_STMT_WHILE {
                 let id = self.consume_while_statement(module, iter, ctx)?;
                 return Ok(id.upcast());
             } else if ident == KW_STMT_BREAK {
                 let id = self.consume_break_statement(module, iter, ctx)?;
                 return Ok(id.upcast());
             } else if ident == KW_STMT_CONTINUE {
                 let id = self.consume_continue_statement(module, iter, ctx)?;
                 return Ok(id.upcast());
             } else if ident == KW_STMT_SYNC {
                 let id = self.consume_synchronous_statement(module, iter, ctx)?;
                 return Ok(id.upcast());
             } else if ident == KW_STMT_FORK {
                 let id = self.consume_fork_statement(module, iter, ctx)?;
                 let end_fork = ctx.heap.alloc_end_fork_statement(|this| EndForkStatement {
                     this,
                     start_fork: id,
                     next: StatementId::new_invalid(),
                 });
                 let fork_stmt = &mut ctx.heap[id];
                 fork_stmt.end_fork = end_fork;
                 return Ok(id.upcast());
             } else if ident == KW_STMT_SELECT {
                 let id = self.consume_select_statement(module, iter, ctx)?;
                 return Ok(id.upcast());
             } else if ident == KW_STMT_RETURN {
                 let id = self.consume_return_statement(module, iter, ctx)?;
                 return Ok(id.upcast());
             } else if ident == KW_STMT_GOTO {
                 let id = self.consume_goto_statement(module, iter, ctx)?;
                 return Ok(id.upcast());
             } else if ident == KW_STMT_NEW {
                 let id = self.consume_new_statement(module, iter, ctx)?;
                 return Ok(id.upcast());
             } else if ident == KW_STMT_CHANNEL {
                 let id = self.consume_channel_statement(module, iter, ctx)?;
                 return Ok(id.upcast().upcast());
             } else if iter.peek() == Some(TokenKind::Colon) {
                 let id = self.consume_labeled_statement(module, iter, ctx)?;
                 return Ok(id.upcast());
             } else {
                 // Two fallback possibilities: the first one is a memory
                 // declaration, the other one is to parse it as a normal
                 // expression. This is a bit ugly.
                 if let Some(memory_stmt_id) = self.maybe_consume_memory_statement_without_semicolon(module, iter, ctx)? {
                     consume_token(&module.source, iter, TokenKind::SemiColon)?;
                     return Ok(memory_stmt_id.upcast().upcast());
                 } else {
                     let id = self.consume_expression_statement(module, iter, ctx)?;
                     return Ok(id.upcast());
+                }
+            }
         } else if next == TokenKind::OpenParen {
             // Same as above: memory statement or normal expression
             if let Some(memory_stmt_id) = self.maybe_consume_memory_statement_without_semicolon(module, iter, ctx)? {
                 consume_token(&module.source, iter, TokenKind::SemiColon)?;
                 return Ok(memory_stmt_id.upcast().upcast());
             } else {
                 let id = self.consume_expression_statement(module, iter, ctx)?;
                 return Ok(id.upcast());
+            }
         } else {
             let id = self.consume_expression_statement(module, iter, ctx)?;
             return Ok(id.upcast());
+        }
+    }
     fn consume_block_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<BlockStatementId, ParseError> {
         let open_curly_span = consume_token(&module.source, iter, TokenKind::OpenCurly)?;
         let mut stmt_section = self.statements.start_section();
         let mut next = iter.next();
         while next != Some(TokenKind::CloseCurly) {
             if next.is_none() {
                 return Err(ParseError::new_error_str_at_pos(
                     &module.source, iter.last_valid_pos(), "expected a statement or '}'"
                 ));
+            }
             let stmt_id = self.consume_statement(module, iter, ctx)?;
             stmt_section.push(stmt_id);
             next = iter.next();
+        }
         let statements = stmt_section.into_vec();
         let mut block_span = consume_token(&module.source, iter, TokenKind::CloseCurly)?;
         block_span.begin = open_curly_span.begin;
         let block_id = ctx.heap.alloc_block_statement(|this| BlockStatement{
             this,
             span: block_span,
             statements,
             end_block: EndBlockStatementId::new_invalid(),
             scope: ScopeId::new_invalid(),
             next: StatementId::new_invalid(),
         });
         let scope_id = ctx.heap.alloc_scope(|this| Scope::new(this, ScopeAssociation::Block(block_id)));
         let end_block_id = ctx.heap.alloc_end_block_statement(|this| EndBlockStatement{
             this, start_block: block_id, next: StatementId::new_invalid()
         });
         let block_stmt = &mut ctx.heap[block_id];
         block_stmt.end_block = end_block_id;
         block_stmt.scope = scope_id;
         Ok(block_id)
+    }
     fn consume_if_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<IfStatementId, ParseError> {
         let if_span = consume_exact_ident(&module.source, iter, KW_STMT_IF)?;
         consume_token(&module.source, iter, TokenKind::OpenParen)?;
         let test = self.consume_expression(module, iter, ctx)?;
         consume_token(&module.source, iter, TokenKind::CloseParen)?;
         // Consume bodies of if-statement
         let true_body = IfStatementCase{
             body: self.consume_statement(module, iter, ctx)?,
             scope: ScopeId::new_invalid(),
         };
         let false_body = if has_ident(&module.source, iter, KW_STMT_ELSE) {
             iter.consume();
             let false_body = IfStatementCase{
                 body: self.consume_statement(module, iter, ctx)?,
                 scope: ScopeId::new_invalid(),
             };
             Some(false_body)
         } else {
             None
         };
         // Construct AST elements
         let if_stmt_id = ctx.heap.alloc_if_statement(|this| IfStatement{
             this,
             span: if_span,
             test,
             true_case: true_body,
             false_case: false_body,
             end_if: EndIfStatementId::new_invalid(),
         });
         let end_if_stmt_id = ctx.heap.alloc_end_if_statement(|this| EndIfStatement{
             this,
             start_if: if_stmt_id,
             next: StatementId::new_invalid(),
         });
         let true_scope_id = ctx.heap.alloc_scope(|this| Scope::new(this, ScopeAssociation::If(if_stmt_id, true)));
         let false_scope_id = if false_body.is_some() {
             Some(ctx.heap.alloc_scope(|this| Scope::new(this, ScopeAssociation::If(if_stmt_id, false))))
         } else {
             None
         };
         let if_stmt = &mut ctx.heap[if_stmt_id];
         if_stmt.end_if = end_if_stmt_id;
         if_stmt.true_case.scope = true_scope_id;
         if let Some(false_case) = &mut if_stmt.false_case {
             false_case.scope = false_scope_id.unwrap();
+        }
         return Ok(if_stmt_id);
+    }
     fn consume_while_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<WhileStatementId, ParseError> {
         let while_span = consume_exact_ident(&module.source, iter, KW_STMT_WHILE)?;
         consume_token(&module.source, iter, TokenKind::OpenParen)?;
         let test = self.consume_expression(module, iter, ctx)?;
         consume_token(&module.source, iter, TokenKind::CloseParen)?;
         let body = self.consume_statement(module, iter, ctx)?;
         let while_stmt_id = ctx.heap.alloc_while_statement(|this| WhileStatement{
             this,
             span: while_span,
             test,
             scope: ScopeId::new_invalid(),
             body,
             end_while: EndWhileStatementId::new_invalid(),
             in_sync: SynchronousStatementId::new_invalid(),
         });
         let end_while_stmt_id = ctx.heap.alloc_end_while_statement(|this| EndWhileStatement{
             this,
             start_while: while_stmt_id,
             next: StatementId::new_invalid(),
         });
         let scope_id = ctx.heap.alloc_scope(|this| Scope::new(this, ScopeAssociation::While(while_stmt_id)));
         let while_stmt = &mut ctx.heap[while_stmt_id];
         while_stmt.scope = scope_id;
         while_stmt.end_while = end_while_stmt_id;
         Ok(while_stmt_id)
+    }
     fn consume_break_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<BreakStatementId, ParseError> {
         let break_span = consume_exact_ident(&module.source, iter, KW_STMT_BREAK)?;
         let label = if Some(TokenKind::Ident) == iter.next() {
             let label = consume_ident_interned(&module.source, iter, ctx)?;
             Some(label)
         } else {
             None
         };
         consume_token(&module.source, iter, TokenKind::SemiColon)?;
         Ok(ctx.heap.alloc_break_statement(|this| BreakStatement{
             this,
             span: break_span,
             label,
             target: EndWhileStatementId::new_invalid(),
         }))
+    }
     fn consume_continue_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ContinueStatementId, ParseError> {
         let continue_span = consume_exact_ident(&module.source, iter, KW_STMT_CONTINUE)?;
         let label=  if Some(TokenKind::Ident) == iter.next() {
             let label = consume_ident_interned(&module.source, iter, ctx)?;
             Some(label)
         } else {
             None
         };
         consume_token(&module.source, iter, TokenKind::SemiColon)?;
         Ok(ctx.heap.alloc_continue_statement(|this| ContinueStatement{
             this,
             span: continue_span,
             label,
             target: WhileStatementId::new_invalid(),
         }))
+    }
     fn consume_synchronous_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<SynchronousStatementId, ParseError> {
         let synchronous_span = consume_exact_ident(&module.source, iter, KW_STMT_SYNC)?;
         let body = self.consume_statement(module, iter, ctx)?;
         let sync_stmt_id = ctx.heap.alloc_synchronous_statement(|this| SynchronousStatement{
             this,
             span: synchronous_span,
             scope: ScopeId::new_invalid(),
             body,
             end_sync: EndSynchronousStatementId::new_invalid(),
         });
         let end_sync_stmt_id = ctx.heap.alloc_end_synchronous_statement(|this| EndSynchronousStatement{
             this,
             start_sync: sync_stmt_id,
             next: StatementId::new_invalid(),
         });
         let scope_id = ctx.heap.alloc_scope(|this| Scope::new(this, ScopeAssociation::Synchronous(sync_stmt_id)));
         let sync_stmt = &mut ctx.heap[sync_stmt_id];
         sync_stmt.scope = scope_id;
         sync_stmt.end_sync = end_sync_stmt_id;
         return Ok(sync_stmt_id);
+    }
     fn consume_fork_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ForkStatementId, ParseError> {
         let fork_span = consume_exact_ident(&module.source, iter, KW_STMT_FORK)?;
         let left_body = self.consume_statement(module, iter, ctx)?;
         let right_body = if has_ident(&module.source, iter, KW_STMT_OR) {
             iter.consume();
             let right_body = self.consume_statement(module, iter, ctx)?;
             Some(right_body)
         } else {
             None
         };
         Ok(ctx.heap.alloc_fork_statement(|this| ForkStatement{
             this,
             span: fork_span,
             left_body,
             right_body,
             end_fork: EndForkStatementId::new_invalid(),
         }))
+    }
     fn consume_select_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<SelectStatementId, ParseError> {
         let select_span = consume_exact_ident(&module.source, iter, KW_STMT_SELECT)?;
         consume_token(&module.source, iter, TokenKind::OpenCurly)?;
         let mut cases = Vec::new();
         let mut next = iter.next();
         while Some(TokenKind::CloseCurly) != next {
             let guard = match self.maybe_consume_memory_statement_without_semicolon(module, iter, ctx)? {
                 Some(guard_mem_stmt) => guard_mem_stmt.upcast().upcast(),
                 None => {
                     let start_pos = iter.last_valid_pos();
                     let expr = self.consume_expression(module, iter, ctx)?;
                     let end_pos = iter.last_valid_pos();
                     let guard_expr_stmt = ctx.heap.alloc_expression_statement(|this| ExpressionStatement{
                         this,
                         span: InputSpan::from_positions(start_pos, end_pos),
                         expression: expr,
                         next: StatementId::new_invalid(),
                     });
                     guard_expr_stmt.upcast()
                 },
             };
             consume_token(&module.source, iter, TokenKind::ArrowRight)?;
             let block = self.consume_statement(module, iter, ctx)?;
             cases.push(SelectCase{
                 guard,
                 body: block,
                 scope: ScopeId::new_invalid(),
                 involved_ports: Vec::with_capacity(1)
             });
             next = iter.next();
+        }
         consume_token(&module.source, iter, TokenKind::CloseCurly)?;
         let num_cases = cases.len();
         let select_stmt_id = ctx.heap.alloc_select_statement(|this| SelectStatement{
             this,
             span: select_span,
             cases,
             end_select: EndSelectStatementId::new_invalid(),
             relative_pos_in_parent: -1,
             next: StatementId::new_invalid(),
         });
         let end_select_stmt_id = ctx.heap.alloc_end_select_statement(|this| EndSelectStatement{
             this,
             start_select: select_stmt_id,
             next: StatementId::new_invalid(),
         });
         let select_stmt = &mut ctx.heap[select_stmt_id];
         select_stmt.end_select = end_select_stmt_id;
         for case_index in 0..num_cases {
             let scope_id = ctx.heap.alloc_scope(|this| Scope::new(this, ScopeAssociation::SelectCase(select_stmt_id, case_index as u32)));
             let select_stmt = &mut ctx.heap[select_stmt_id];
             let select_case = &mut select_stmt.cases[case_index];
             select_case.scope = scope_id;
+        }
         return Ok(select_stmt_id)
+    }
     fn consume_return_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ReturnStatementId, ParseError> {
         let return_span = consume_exact_ident(&module.source, iter, KW_STMT_RETURN)?;
         let mut scoped_section = self.expressions.start_section();
         consume_comma_separated_until(
             TokenKind::SemiColon, &module.source, iter, ctx,
             |_source, iter, ctx| self.consume_expression(module, iter, ctx),
             &mut scoped_section, "an expression", None
         )?;
         let expressions = scoped_section.into_vec();
         if expressions.is_empty() {
             return Err(ParseError::new_error_str_at_span(&module.source, return_span, "expected at least one return value"));
         } else if expressions.len() > 1 {
             return Err(ParseError::new_error_str_at_span(&module.source, return_span, "multiple return values are not (yet) supported"))
+        }
         Ok(ctx.heap.alloc_return_statement(|this| ReturnStatement{
             this,
             span: return_span,
             expressions
         }))
+    }
     fn consume_goto_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<GotoStatementId, ParseError> {
         let goto_span = consume_exact_ident(&module.source, iter, KW_STMT_GOTO)?;
         let label = consume_ident_interned(&module.source, iter, ctx)?;
         consume_token(&module.source, iter, TokenKind::SemiColon)?;
         Ok(ctx.heap.alloc_goto_statement(|this| GotoStatement{
             this,
             span: goto_span,
             label,
             target: LabeledStatementId::new_invalid(),
         }))
+    }
     fn consume_new_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<NewStatementId, ParseError> {
         let new_span = consume_exact_ident(&module.source, iter, KW_STMT_NEW)?;
         let start_pos = iter.last_valid_pos();
         let expression_id = self.consume_primary_expression(module, iter, ctx)?;
         let expression = &ctx.heap[expression_id];
         let mut valid = false;
         let mut call_id = CallExpressionId::new_invalid();
         if let Expression::Call(expression) = expression {
             // Allow both components and functions, as it makes more sense to
             // check their correct use in the validation and linking pass
             call_id = expression.this;
             valid = true;
+        }
         if !valid {
             return Err(ParseError::new_error_str_at_span(
                 &module.source, InputSpan::from_positions(start_pos, iter.last_valid_pos()), "expected a call expression"
             ));
+        }
         consume_token(&module.source, iter, TokenKind::SemiColon)?;
         debug_assert!(!call_id.is_invalid());
         Ok(ctx.heap.alloc_new_statement(|this| NewStatement{
             this,
             span: new_span,
             expression: call_id,
             next: StatementId::new_invalid(),
         }))
+    }
     fn consume_channel_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ChannelStatementId, ParseError> {
         // Consume channel specification
         let channel_span = consume_exact_ident(&module.source, iter, KW_STMT_CHANNEL)?;
         let (inner_port_type, end_pos) = if Some(TokenKind::OpenAngle) == iter.next() {
             // Retrieve the type of the channel, we're cheating a bit here by
             // consuming the first '<' and setting the initial angle depth to 1
             // such that our final '>' will be consumed as well.
             let angle_start_pos = iter.next_start_position();
             iter.consume();
             let definition_id = self.cur_definition;
             let poly_vars = ctx.heap[definition_id].poly_vars();
             let parser_type = self.type_parser.consume_parser_type(
                 iter, &ctx.heap, &module.source, &ctx.symbols, poly_vars,
                 definition_id, SymbolScope::Module(module.root_id),
                 true, false, Some(angle_start_pos)
             )?;
             (parser_type.elements, parser_type.full_span.end)
         } else {
             // Assume inferred
+            (
                 vec![ParserTypeElement{
                     element_span: channel_span,
                     variant: ParserTypeVariant::Inferred
                 }],
                 channel_span.end
+            )
         };
         let from_identifier = consume_ident_interned(&module.source, iter, ctx)?;
         consume_token(&module.source, iter, TokenKind::ArrowRight)?;
         let to_identifier = consume_ident_interned(&module.source, iter, ctx)?;
         consume_token(&module.source, iter, TokenKind::SemiColon)?;
         // Construct ports
         let port_type_span = InputSpan::from_positions(channel_span.begin, end_pos);
         let port_type_len = inner_port_type.len() + 1;
         let mut from_port_type = ParserType{ elements: Vec::with_capacity(port_type_len), full_span: port_type_span };
         from_port_type.elements.push(ParserTypeElement{
             element_span: channel_span,
             variant: ParserTypeVariant::Output,
         });
         from_port_type.elements.extend_from_slice(&inner_port_type);
         let from = ctx.heap.alloc_variable(|this| Variable{
             this,
             kind: VariableKind::Local,
             identifier: from_identifier,
             parser_type: from_port_type,
             relative_pos_in_parent: 0,
             unique_id_in_scope: -1,
         });
         let mut to_port_type = ParserType{ elements: Vec::with_capacity(port_type_len), full_span: port_type_span };
         to_port_type.elements.push(ParserTypeElement{
             element_span: channel_span,
             variant: ParserTypeVariant::Input
         });
         to_port_type.elements.extend_from_slice(&inner_port_type);
         let to = ctx.heap.alloc_variable(|this|Variable{
             this,
             kind: VariableKind::Local,
             identifier: to_identifier,
             parser_type: to_port_type,
             relative_pos_in_parent: 0,
             unique_id_in_scope: -1,
         });
         // Construct the channel
         Ok(ctx.heap.alloc_channel_statement(|this| ChannelStatement{
             this,
             span: channel_span,
             from, to,
             relative_pos_in_parent: 0,
             next: StatementId::new_invalid(),
         }))
+    }
     fn consume_labeled_statement(&mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx) -> Result<LabeledStatementId, ParseError> {
         let label = consume_ident_interned(&module.source, iter, ctx)?;
         consume_token(&module.source, iter, TokenKind::Colon)?;
         let inner_stmt_id = self.consume_statement(module, iter, ctx)?;
         let stmt_id = ctx.heap.alloc_labeled_statement(|this| LabeledStatement {
             this,
             label,
             body: inner_stmt_id,
             relative_pos_in_parent: 0,
             in_sync: SynchronousStatementId::new_invalid(),
         });
         return Ok(stmt_id);
+    }
     /// Attempts to consume a memory statement (a statement along the lines of
     /// `type var_name = initial_expr`). Will return `Ok(None)` if it didn't
     /// seem like there was a memory statement, `Ok(Some(...))` if there was
     /// one, and `Err(...)` if its reasonable to assume that there was a memory
     /// statement, but we failed to parse it.
     fn maybe_consume_memory_statement_without_semicolon(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<Option<MemoryStatementId>, ParseError> {
         // This is a bit ugly. It would be nicer if we could somehow
         // consume the expression with a type hint if we do get a valid
         // type, but we don't get an identifier following it
         let iter_state = iter.save();
         let definition_id = self.cur_definition;
         let poly_vars = ctx.heap[definition_id].poly_vars();
         let parser_type = self.type_parser.consume_parser_type(
             iter, &ctx.heap, &module.source, &ctx.symbols, poly_vars,
             definition_id, SymbolScope::Definition(definition_id),
             true, false, None
         );
         if let Ok(parser_type) = parser_type {
             if Some(TokenKind::Ident) == iter.next() {
                 // Assume this is a proper memory statement
                 let identifier = consume_ident_interned(&module.source, iter, ctx)?;
                 let memory_span = InputSpan::from_positions(parser_type.full_span.begin, identifier.span.end);
                 let assign_span = consume_token(&module.source, iter, TokenKind::Equal)?;
                 let initial_expr_id = self.consume_expression(module, iter, ctx)?;
                 let initial_expr_end_pos = iter.last_valid_pos();
                 // Create the AST variable
                 let local_id = ctx.heap.alloc_variable(|this| Variable{
                     this,
                     kind: VariableKind::Local,
                     identifier: identifier.clone(),
                     parser_type,
                     relative_pos_in_parent: 0,
                     unique_id_in_scope: -1,
                 });
                 // Create the initial assignment expression
                 // Note: we set the initial variable declaration here
                 let variable_expr_id = ctx.heap.alloc_variable_expression(|this| VariableExpression{
                     this,
                     identifier,
                     declaration: Some(local_id),
                     used_as_binding_target: false,
                     parent: ExpressionParent::None,
                     type_index: -1,
                 });
                 let assignment_expr_id = ctx.heap.alloc_assignment_expression(|this| AssignmentExpression{
                     this,
                     operator_span: assign_span,
                     full_span: InputSpan::from_positions(memory_span.begin, initial_expr_end_pos),
                     left: variable_expr_id.upcast(),
                     operation: AssignmentOperator::Set,
                     right: initial_expr_id,
                     parent: ExpressionParent::None,
                     type_index: -1,
                 });
                 // Put both together in the memory statement
                 let memory_stmt_id = ctx.heap.alloc_memory_statement(|this| MemoryStatement{
                     this,
                     span: memory_span,
                     variable: local_id,
                     initial_expr: assignment_expr_id,
                     next: StatementId::new_invalid()
                 });
                 return Ok(Some(memory_stmt_id));
+            }
+        }
         // If here then one of the preconditions for a memory statement was not
         // met. So recover the iterator and return
         iter.load(iter_state);
         Ok(None)
+    }
     fn consume_expression_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionStatementId, ParseError> {
         let start_pos = iter.last_valid_pos();
         let expression = self.consume_expression(module, iter, ctx)?;
         let end_pos = iter.last_valid_pos();
         consume_token(&module.source, iter, TokenKind::SemiColon)?;
         Ok(ctx.heap.alloc_expression_statement(|this| ExpressionStatement{
             this,
             span: InputSpan::from_positions(start_pos, end_pos),
             expression,
             next: StatementId::new_invalid(),
         }))
+    }
     //--------------------------------------------------------------------------
     // Expression Parsing
     //--------------------------------------------------------------------------
     // TODO: @Cleanup This is fine for now. But I prefer my stacktraces not to
     //  look like enterprise Java code...
     fn consume_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         self.consume_assignment_expression(module, iter, ctx)
+    }
     fn consume_assignment_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         // Utility to convert token into assignment operator
         fn parse_assignment_operator(token: Option<TokenKind>) -> Option<AssignmentOperator> {
             use TokenKind as TK;
             use AssignmentOperator as AO;
             if token.is_none() {
                 return None
+            }
             match token.unwrap() {
                 TK::Equal               => Some(AO::Set),
                 TK::AtEquals            => Some(AO::Concatenated),
                 TK::StarEquals          => Some(AO::Multiplied),
                 TK::SlashEquals         => Some(AO::Divided),
                 TK::PercentEquals       => Some(AO::Remained),
                 TK::PlusEquals          => Some(AO::Added),
                 TK::MinusEquals         => Some(AO::Subtracted),
                 TK::ShiftLeftEquals     => Some(AO::ShiftedLeft),
                 TK::ShiftRightEquals    => Some(AO::ShiftedRight),
                 TK::AndEquals           => Some(AO::BitwiseAnded),
                 TK::CaretEquals         => Some(AO::BitwiseXored),
                 TK::OrEquals            => Some(AO::BitwiseOred),
                 _                       => None
+            }
+        }
         let expr = self.consume_conditional_expression(module, iter, ctx)?;
         if let Some(operation) = parse_assignment_operator(iter.next()) {
             let operator_span = iter.next_span();
             iter.consume();
             let left = expr;
             let right = self.consume_expression(module, iter, ctx)?;
             let full_span = InputSpan::from_positions(
                 ctx.heap[left].full_span().begin,
                 ctx.heap[right].full_span().end,
             );
             Ok(ctx.heap.alloc_assignment_expression(|this| AssignmentExpression{
                 this, operator_span, full_span, left, operation, right,
                 parent: ExpressionParent::None,
                 type_index: -1,
             }).upcast())
         } else {
             Ok(expr)
+        }
+    }
     fn consume_conditional_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         let result = self.consume_concat_expression(module, iter, ctx)?;
         if let Some(TokenKind::Question) = iter.next() {
             let operator_span = iter.next_span();
             iter.consume();
             let test = result;
             let true_expression = self.consume_expression(module, iter, ctx)?;
             consume_token(&module.source, iter, TokenKind::Colon)?;
             let false_expression = self.consume_expression(module, iter, ctx)?;
             let full_span = InputSpan::from_positions(
                 ctx.heap[test].full_span().begin,
                 ctx.heap[false_expression].full_span().end,
             );
             Ok(ctx.heap.alloc_conditional_expression(|this| ConditionalExpression{
                 this, operator_span, full_span, test, true_expression, false_expression,
                 parent: ExpressionParent::None,
                 type_index: -1,
             }).upcast())
         } else {
             Ok(result)
+        }
+    }
     fn consume_concat_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         self.consume_generic_binary_expression(
             module, iter, ctx,
             |token| match token {
                 Some(TokenKind::At) => Some(BinaryOperator::Concatenate),
                 _ => None
             },
             Self::consume_logical_or_expression
+        )
+    }
     fn consume_logical_or_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         self.consume_generic_binary_expression(
             module, iter, ctx,
             |token| match token {
                 Some(TokenKind::OrOr) => Some(BinaryOperator::LogicalOr),
                 _ => None
             },
             Self::consume_logical_and_expression
+        )
+    }
     fn consume_logical_and_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         self.consume_generic_binary_expression(
             module, iter, ctx,
             |token| match token {
                 Some(TokenKind::AndAnd) => Some(BinaryOperator::LogicalAnd),
                 _ => None
             },
             Self::consume_bitwise_or_expression
+        )
+    }
     fn consume_bitwise_or_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         self.consume_generic_binary_expression(
             module, iter, ctx,
             |token| match token {
                 Some(TokenKind::Or) => Some(BinaryOperator::BitwiseOr),
                 _ => None
             },
             Self::consume_bitwise_xor_expression
+        )
+    }
     fn consume_bitwise_xor_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         self.consume_generic_binary_expression(
             module, iter, ctx,
             |token| match token {
                 Some(TokenKind::Caret) => Some(BinaryOperator::BitwiseXor),
                 _ => None
             },
             Self::consume_bitwise_and_expression
+        )
+    }
     fn consume_bitwise_and_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         self.consume_generic_binary_expression(
             module, iter, ctx,
             |token| match token {
                 Some(TokenKind::And) => Some(BinaryOperator::BitwiseAnd),
                 _ => None
             },
             Self::consume_equality_expression
+        )
+    }
     fn consume_equality_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         self.consume_generic_binary_expression(
             module, iter, ctx,
             |token| match token {
                 Some(TokenKind::EqualEqual) => Some(BinaryOperator::Equality),
                 Some(TokenKind::NotEqual) => Some(BinaryOperator::Inequality),
                 _ => None
             },
             Self::consume_relational_expression
+        )
+    }
     fn consume_relational_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         self.consume_generic_binary_expression(
             module, iter, ctx,
             |token| match token {
                 Some(TokenKind::OpenAngle) => Some(BinaryOperator::LessThan),
                 Some(TokenKind::CloseAngle) => Some(BinaryOperator::GreaterThan),
                 Some(TokenKind::LessEquals) => Some(BinaryOperator::LessThanEqual),
                 Some(TokenKind::GreaterEquals) => Some(BinaryOperator::GreaterThanEqual),
                 _ => None
             },
             Self::consume_shift_expression
+        )
+    }
     fn consume_shift_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         self.consume_generic_binary_expression(
             module, iter, ctx,
             |token| match token {
                 Some(TokenKind::ShiftLeft) => Some(BinaryOperator::ShiftLeft),
                 Some(TokenKind::ShiftRight) => Some(BinaryOperator::ShiftRight),
                 _ => None
             },
             Self::consume_add_or_subtract_expression
+        )
+    }
     fn consume_add_or_subtract_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         self.consume_generic_binary_expression(
             module, iter, ctx,
             |token| match token {
                 Some(TokenKind::Plus) => Some(BinaryOperator::Add),
                 Some(TokenKind::Minus) => Some(BinaryOperator::Subtract),
                 _ => None,
             },
             Self::consume_multiply_divide_or_modulus_expression
+        )
+    }
     fn consume_multiply_divide_or_modulus_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         self.consume_generic_binary_expression(
             module, iter, ctx,
             |token| match token {
                 Some(TokenKind::Star) => Some(BinaryOperator::Multiply),
                 Some(TokenKind::Slash) => Some(BinaryOperator::Divide),
                 Some(TokenKind::Percent) => Some(BinaryOperator::Remainder),
                 _ => None
             },
             Self::consume_prefix_expression
+        )
+    }
     fn consume_prefix_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         fn parse_prefix_token(token: Option<TokenKind>) -> Option<UnaryOperator> {
             use TokenKind as TK;
             use UnaryOperator as UO;
             match token {
                 Some(TK::Plus) => Some(UO::Positive),
                 Some(TK::Minus) => Some(UO::Negative),
                 Some(TK::Tilde) => Some(UO::BitwiseNot),
                 Some(TK::Exclamation) => Some(UO::LogicalNot),
                 _ => None
+            }
+        }
         let next = iter.next();
         if let Some(operation) = parse_prefix_token(next) {
             let operator_span = iter.next_span();
             iter.consume();
             let expression = self.consume_prefix_expression(module, iter, ctx)?;
             let full_span = InputSpan::from_positions(
                 operator_span.begin, ctx.heap[expression].full_span().end,
             );
             Ok(ctx.heap.alloc_unary_expression(|this| UnaryExpression {
                 this, operator_span, full_span, operation, expression,
                 parent: ExpressionParent::None,
                 type_index: -1,
             }).upcast())
         } else if next == Some(TokenKind::PlusPlus) {
             return Err(ParseError::new_error_str_at_span(
                 &module.source, iter.next_span(), "prefix increment is not supported in the language"
             ));
         } else if next == Some(TokenKind::MinusMinus) {
             return Err(ParseError::new_error_str_at_span(
                 &module.source, iter.next_span(), "prefix decrement is not supported in this language"
             ));
         } else {
             self.consume_postfix_expression(module, iter, ctx)
+        }
+    }
     fn consume_postfix_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         fn has_matching_postfix_token(token: Option<TokenKind>) -> bool {
             use TokenKind as TK;
             if token.is_none() { return false; }
             match token.unwrap() {
                 TK::PlusPlus | TK::MinusMinus | TK::OpenSquare | TK::Dot => true,
                 _ => false
+            }
+        }
         let mut result = self.consume_primary_expression(module, iter, ctx)?;
         let mut next = iter.next();
         while has_matching_postfix_token(next) {
             let token = next.unwrap();
             let mut operator_span = iter.next_span();
             iter.consume();
             if token == TokenKind::PlusPlus {
                 return Err(ParseError::new_error_str_at_span(
                     &module.source, operator_span, "postfix increment is not supported in this language"
                 ));
             } else if token == TokenKind::MinusMinus {
                 return Err(ParseError::new_error_str_at_span(
                     &module.source, operator_span, "prefix increment is not supported in this language"
                 ));
             } else if token == TokenKind::OpenSquare {
                 let subject = result;
                 let from_index = self.consume_expression(module, iter, ctx)?;
                 // Check if we have an indexing or slicing operation
                 next = iter.next();
                 if Some(TokenKind::DotDot) == next {
                     iter.consume();
                     let to_index = self.consume_expression(module, iter, ctx)?;
                     let end_span = consume_token(&module.source, iter, TokenKind::CloseSquare)?;
                     operator_span.end = end_span.end;
                     let full_span = InputSpan::from_positions(
                         ctx.heap[subject].full_span().begin, operator_span.end
                     );
                     result = ctx.heap.alloc_slicing_expression(|this| SlicingExpression{
                         this,
                         slicing_span: operator_span,
                         full_span, subject, from_index, to_index,
                         parent: ExpressionParent::None,
                         type_index: -1,
                     }).upcast();
                 } else if Some(TokenKind::CloseSquare) == next {
                     let end_span = consume_token(&module.source, iter, TokenKind::CloseSquare)?;
                     operator_span.end = end_span.end;
                     let full_span = InputSpan::from_positions(
                         ctx.heap[subject].full_span().begin, operator_span.end
                     );
                     result = ctx.heap.alloc_indexing_expression(|this| IndexingExpression{
                         this, operator_span, full_span, subject,
                         index: from_index,
                         parent: ExpressionParent::None,
                         type_index: -1,
                     }).upcast();
                 } else {
                     return Err(ParseError::new_error_str_at_pos(
                         &module.source, iter.last_valid_pos(), "unexpected token: expected ']' or '..'"
                     ));
+                }
             } else {
                 // Can be a select expression for struct fields, or a select
                 // for a tuple element.
                 debug_assert_eq!(token, TokenKind::Dot);
                 let subject = result;
                 let next = iter.next();
                 let (select_kind, full_span) = if Some(TokenKind::Integer) == next {
                     // Tuple member
                     let (index, index_span) = consume_integer_literal(&module.source, iter, &mut self.buffer)?;
                     let full_span = InputSpan::from_positions(
                         ctx.heap[subject].full_span().begin, index_span.end
                     );
                     (SelectKind::TupleMember(index), full_span)
                 } else if Some(TokenKind::Ident) == next {
                     // Struct field
                     let field_name = consume_ident_interned(&module.source, iter, ctx)?;
                     let full_span = InputSpan::from_positions(
                         ctx.heap[subject].full_span().begin, field_name.span.end
                     );
                     (SelectKind::StructField(field_name), full_span)
                 } else {
                     return Err(ParseError::new_error_str_at_pos(
                         &module.source, iter.last_valid_pos(), "unexpected token: expected integer or identifier"
                     ));
                 };
                 result = ctx.heap.alloc_select_expression(|this| SelectExpression{
                     this, operator_span, full_span, subject,
                     kind: select_kind,
                     parent: ExpressionParent::None,
                     type_index: -1,
                 }).upcast();
+            }
             next = iter.next();
+        }
         Ok(result)
+    }
     fn consume_primary_expression(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ExpressionId, ParseError> {
         let next = iter.next();
         let result = if next == Some(TokenKind::OpenParen) {
             // Something parenthesized. This can mean several things: we have
             // a parenthesized expression or we have a tuple literal. They are
             // ambiguous when the tuple has one member. But like the tuple type
             // parsing we interpret all one-tuples as parenthesized expressions.
             //
             // Practically (to prevent unnecessary `consume_expression` calls)
             // we distinguish the zero-tuple, the parenthesized expression, and
             // the N-tuple (for N > 1).
             let open_paren_pos = iter.next_start_position();
             iter.consume();
             let result = if Some(TokenKind::CloseParen) == iter.next() {
                 // Zero-tuple
                 let (_, close_paren_pos) = iter.next_positions();
                 iter.consume();
                 let literal_id = ctx.heap.alloc_literal_expression(|this| LiteralExpression{
                     this,
                     span: InputSpan::from_positions(open_paren_pos, close_paren_pos),
                     value: Literal::Tuple(Vec::new()),
                     parent: ExpressionParent::None,
                     type_index: -1,
                 });
                 literal_id.upcast()
             } else {
                 // Start by consuming one expression, then check for a comma
                 let expr_id = self.consume_expression(module, iter, ctx)?;
                 if Some(TokenKind::Comma) == iter.next() && Some(TokenKind::CloseParen) != iter.peek() {
                     // Must be an N-tuple
                     iter.consume(); // the comma
                     let mut scoped_section = self.expressions.start_section();
                     scoped_section.push(expr_id);
                     let mut close_paren_pos = open_paren_pos;
                     consume_comma_separated_until(
                         TokenKind::CloseParen, &module.source, iter, ctx,
                         |_source, iter, ctx| self.consume_expression(module, iter, ctx),
                         &mut scoped_section, "an expression", Some(&mut close_paren_pos)
                     )?;
                     debug_assert!(scoped_section.len() > 1); // peeked token wasn't CloseParen, must be expression
                     let literal_id = ctx.heap.alloc_literal_expression(|this| LiteralExpression{
                         this,
                         span: InputSpan::from_positions(open_paren_pos, close_paren_pos),
                         value: Literal::Tuple(scoped_section.into_vec()),
                         parent: ExpressionParent::None,
                         type_index: -1,
                     });
                     literal_id.upcast()
                 } else {
                     // Assume we're dealing with a normal expression
                     consume_token(&module.source, iter, TokenKind::CloseParen)?;
                     expr_id
+                }
             };
             result
         } else if next == Some(TokenKind::OpenCurly) {
             // Array literal
             let (start_pos, mut end_pos) = iter.next_positions();
             let mut scoped_section = self.expressions.start_section();
             consume_comma_separated(
                 TokenKind::OpenCurly, TokenKind::CloseCurly, &module.source, iter, ctx,
                 |_source, iter, ctx| self.consume_expression(module, iter, ctx),
                 &mut scoped_section, "an expression", "a list of expressions", Some(&mut end_pos)
             )?;
             ctx.heap.alloc_literal_expression(|this| LiteralExpression{
                 this,
                 span: InputSpan::from_positions(start_pos, end_pos),
                 value: Literal::Array(scoped_section.into_vec()),
                 parent: ExpressionParent::None,
                 type_index: -1,
             }).upcast()
         } else if next == Some(TokenKind::Integer) {
             let (literal, span) = consume_integer_literal(&module.source, iter, &mut self.buffer)?;
             ctx.heap.alloc_literal_expression(|this| LiteralExpression {
                 this,
                 span,
                 value: Literal::Integer(LiteralInteger { unsigned_value: literal, negated: false }),
                 parent: ExpressionParent::None,
                 type_index: -1,
             }).upcast()
         } else if next == Some(TokenKind::Bytestring) {
             let span = consume_bytestring_literal(&module.source, iter, &mut self.buffer)?;
             let mut bytes = Vec::with_capacity(self.buffer.len());
             for byte in self.buffer.as_bytes().iter().copied() {
                 bytes.push(byte);
+            }
             ctx.heap.alloc_literal_expression(|this| LiteralExpression{
                 this, span,
                 value: Literal::Bytestring(bytes),
                 parent: ExpressionParent::None,
                 type_index: -1
             }).upcast()
         } else if next == Some(TokenKind::String) {
             let span = consume_string_literal(&module.source, iter, &mut self.buffer)?;
             let interned = ctx.pool.intern(self.buffer.as_bytes());
             ctx.heap.alloc_literal_expression(|this| LiteralExpression{
                 this, span,
                 value: Literal::String(interned),
                 parent: ExpressionParent::None,
                 type_index: -1,
             }).upcast()
         } else if next == Some(TokenKind::Character) {
             let (character, span) = consume_character_literal(&module.source, iter)?;
             ctx.heap.alloc_literal_expression(|this| LiteralExpression{
                 this, span,
                 value: Literal::Character(character),
                 parent: ExpressionParent::None,
                 type_index: -1,
             }).upcast()
         } else if next == Some(TokenKind::Ident) {
             // May be a variable, a type instantiation or a function call. If we
             // have a single identifier that we cannot find in the type table
             // then we're going to assume that we're dealing with a variable.
             let ident_span = iter.next_span();
             let ident_text = module.source.section_at_span(ident_span);
             let symbol = ctx.symbols.get_symbol_by_name(SymbolScope::Module(module.root_id), ident_text);
             if symbol.is_some() {
                 // The first bit looked like a symbol, so we're going to follow
                 // that all the way through, assume we arrive at some kind of
                 // function call or type instantiation
                 use ParserTypeVariant as PTV;
                 let symbol_scope = SymbolScope::Definition(self.cur_definition);
                 let poly_vars = ctx.heap[self.cur_definition].poly_vars();
                 let parser_type = self.type_parser.consume_parser_type(
                     iter, &ctx.heap, &module.source, &ctx.symbols, poly_vars, self.cur_definition,
                     symbol_scope, true, false, None
                 )?;
                 debug_assert!(!parser_type.elements.is_empty());
                 match parser_type.elements[0].variant {
                     PTV::Definition(target_definition_id, _) => {
                         let definition = &ctx.heap[target_definition_id];
                         match definition {
                             Definition::Struct(_) => {
                                 // Struct literal
                                 let mut last_token = iter.last_valid_pos();
                                 let mut struct_fields = Vec::new();
                                 consume_comma_separated(
                                     TokenKind::OpenCurly, TokenKind::CloseCurly, &module.source, iter, ctx,
                                     |source, iter, ctx| {
                                         let identifier = consume_ident_interned(source, iter, ctx)?;
                                         consume_token(source, iter, TokenKind::Colon)?;
                                         let value = self.consume_expression(module, iter, ctx)?;
                                         Ok(LiteralStructField{ identifier, value, field_idx: 0 })
                                     },
                                     &mut struct_fields, "a struct field", "a list of struct fields", Some(&mut last_token)
                                 )?;
                                 ctx.heap.alloc_literal_expression(|this| LiteralExpression{
                                     this,
                                     span: InputSpan::from_positions(ident_span.begin, last_token),
                                     value: Literal::Struct(LiteralStruct{
                                         parser_type,
                                         fields: struct_fields,
                                         definition: target_definition_id,
                                     }),
                                     parent: ExpressionParent::None,
                                     type_index: -1,
                                 }).upcast()
                             },
                             Definition::Enum(_) => {
                                 // Enum literal: consume the variant
                                 consume_token(&module.source, iter, TokenKind::ColonColon)?;
                                 let variant = consume_ident_interned(&module.source, iter, ctx)?;
                                 ctx.heap.alloc_literal_expression(|this| LiteralExpression{
                                     this,
                                     span: InputSpan::from_positions(ident_span.begin, variant.span.end),
                                     value: Literal::Enum(LiteralEnum{
                                         parser_type,
                                         variant,
                                         definition: target_definition_id,
                                         variant_idx: 0
                                     }),
                                     parent: ExpressionParent::None,
                                     type_index: -1,
                                 }).upcast()
                             },
                             Definition::Union(_) => {
                                 // Union literal: consume the variant
                                 consume_token(&module.source, iter, TokenKind::ColonColon)?;
                                 let variant = consume_ident_interned(&module.source, iter, ctx)?;
                                 // Consume any possible embedded values
                                 let mut end_pos = variant.span.end;
                                 let values = if Some(TokenKind::OpenParen) == iter.next() {
                                     self.consume_expression_list(module, iter, ctx, Some(&mut end_pos))?
                                 } else {
                                     Vec::new()
                                 };
                                 ctx.heap.alloc_literal_expression(|this| LiteralExpression{
                                     this,
                                     span: InputSpan::from_positions(ident_span.begin, end_pos),
                                     value: Literal::Union(LiteralUnion{
                                         parser_type, variant, values,
                                         definition: target_definition_id,
                                         variant_idx: 0,
                                     }),
                                     parent: ExpressionParent::None,
                                     type_index: -1,
                                 }).upcast()
                             },
                             Definition::Procedure(proc_def) => {
                                 // Check whether it is a builtin function
                                 // TODO: Once we start generating bytecode this is unnecessary
                                 let procedure_id = proc_def.this;
                                 let method = match proc_def.source {
                                     // Bit of a hack, at this point the source is not yet known, except if it is a
                                     // builtin. So we check for the "kind"
                                     ProcedureSource::FuncUserDefined | ProcedureSource::CompUserDefined => {
                                         match proc_def.kind {
                                             ProcedureKind::Function => Method::UserFunction,
                                             ProcedureKind::Component => Method::UserComponent,
+                                        }
                                     },
                                     ProcedureSource::FuncGet => Method::Get,
                                     ProcedureSource::FuncPut => Method::Put,
                                     ProcedureSource::FuncFires => Method::Fires,
                                     ProcedureSource::FuncCreate => Method::Create,
                                     ProcedureSource::FuncLength => Method::Length,
                                     ProcedureSource::FuncAssert => Method::Assert,
                                     ProcedureSource::FuncPrint => Method::Print,
                                     ProcedureSource::CompRandomU32 => Method::ComponentRandomU32,
                                     ProcedureSource::CompTcpClient => Method::ComponentTcpClient,
                                     ProcedureSource::CompTcpListener => Method::ComponentTcpListener,
                                     _ => todo!("other procedure sources"),
                                 };
                                 // Function call: consume the arguments
                                 let func_span = parser_type.full_span;
                                 let mut full_span = func_span;
                                 let arguments = self.consume_expression_list(
                                     module, iter, ctx, Some(&mut full_span.end)
                                 )?;
                                 ctx.heap.alloc_call_expression(|this| CallExpression{
                                     this, func_span, full_span, parser_type, method, arguments,
                                     procedure: procedure_id,
                                     parent: ExpressionParent::None,
                                     type_index: -1,
                                 }).upcast()
+                            }
+                        }
                     },
                     _ => {
                         return Err(ParseError::new_error_str_at_span(
                             &module.source, parser_type.full_span, "unexpected type in expression"
                         ))
+                    }
+                }
             } else {
                 // Check for builtin keywords or builtin functions
                 if ident_text == KW_LIT_NULL || ident_text == KW_LIT_TRUE || ident_text == KW_LIT_FALSE {
                     iter.consume();
                     // Parse builtin literal
                     let value = match ident_text {
                         KW_LIT_NULL => Literal::Null,
                         KW_LIT_TRUE => Literal::True,
                         KW_LIT_FALSE => Literal::False,
                         _ => unreachable!(),
                     };
                     ctx.heap.alloc_literal_expression(|this| LiteralExpression {
                         this,
                         span: ident_span,
                         value,
                         parent: ExpressionParent::None,
                         type_index: -1,
                     }).upcast()
                 } else if ident_text == KW_LET {
                     // Binding expression
                     let operator_span = iter.next_span();
                     iter.consume();
                     let bound_to = self.consume_prefix_expression(module, iter, ctx)?;
                     consume_token(&module.source, iter, TokenKind::Equal)?;
                     let bound_from = self.consume_prefix_expression(module, iter, ctx)?;
                     let full_span = InputSpan::from_positions(
                         operator_span.begin, ctx.heap[bound_from].full_span().end,
                     );
                     ctx.heap.alloc_binding_expression(|this| BindingExpression{
                         this, operator_span, full_span, bound_to, bound_from,
                         parent: ExpressionParent::None,
                         type_index: -1,
                     }).upcast()
                 } else if ident_text == KW_CAST {
                     // Casting expression
                     iter.consume();
                     let to_type = if Some(TokenKind::OpenAngle) == iter.next() {
                         let angle_start_pos = iter.next_start_position();
                         iter.consume();
                         let definition_id = self.cur_definition;
                         let poly_vars = ctx.heap[definition_id].poly_vars();
                         self.type_parser.consume_parser_type(
                             iter, &ctx.heap, &module.source, &ctx.symbols,
                             poly_vars, definition_id, SymbolScope::Module(module.root_id),
                             true, false, Some(angle_start_pos)
                         )?
                     } else {
                         // Automatic casting with inferred target type
                         ParserType{
                             elements: vec![ParserTypeElement{
                                 element_span: ident_span,
                                 variant: ParserTypeVariant::Inferred,
                             }],
                             full_span: ident_span
+                        }
                     };
                     consume_token(&module.source, iter, TokenKind::OpenParen)?;
                     let subject = self.consume_expression(module, iter, ctx)?;
                     let mut full_span = iter.next_span();
                     full_span.begin = to_type.full_span.begin;
                     consume_token(&module.source, iter, TokenKind::CloseParen)?;
                     ctx.heap.alloc_cast_expression(|this| CastExpression{
                         this,
                         cast_span: to_type.full_span,
                         full_span, to_type, subject,
                         parent: ExpressionParent::None,
                         type_index: -1,
                     }).upcast()
                 } else {
                     // Not a builtin literal, but also not a known type. So we
                     // assume it is a variable expression. Although if we do,
                     // then if a programmer mistyped a struct/function name the
                     // error messages will be rather cryptic. For polymorphic
                     // arguments we can't really do anything at all (because it
                     // uses the '<' token). In the other cases we try to provide
                     // a better error message.
                     iter.consume();
                     let next = iter.next();
                     if Some(TokenKind::ColonColon) == next {
                         return Err(ParseError::new_error_str_at_span(&module.source, ident_span, "unknown identifier"));
                     } else if Some(TokenKind::OpenParen) == next {
                         return Err(ParseError::new_error_str_at_span(
                             &module.source, ident_span,
                             "unknown identifier, did you mistype a union variant's, component's, or function's name?"
                         ));
                     } else if Some(TokenKind::OpenCurly) == next {
                         return Err(ParseError::new_error_str_at_span(
                             &module.source, ident_span,
                             "unknown identifier, did you mistype a struct type's name?"
                         ))
+                    }
                     let ident_text = ctx.pool.intern(ident_text);
                     let identifier = Identifier { span: ident_span, value: ident_text };
                     ctx.heap.alloc_variable_expression(|this| VariableExpression {
                         this,
                         identifier,
                         declaration: None,
                         used_as_binding_target: false,
                         parent: ExpressionParent::None,
                         type_index: -1,
                     }).upcast()
+                }
+            }
         } else {
             return Err(ParseError::new_error_str_at_pos(
                 &module.source, iter.last_valid_pos(), "expected an expression"
             ));
         };
         Ok(result)
+    }
     //--------------------------------------------------------------------------
     // Expression Utilities
     //--------------------------------------------------------------------------
     #[inline]
     fn consume_generic_binary_expression<
         M: Fn(Option<TokenKind>) -> Option<BinaryOperator>,
         F: Fn(&mut PassDefinitions, &Module, &mut TokenIter, &mut PassCtx) -> Result<ExpressionId, ParseError>
     >(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx, match_fn: M, higher_precedence_fn: F
     ) -> Result<ExpressionId, ParseError> {
         let mut result = higher_precedence_fn(self, module, iter, ctx)?;
         while let Some(operation) = match_fn(iter.next()) {
             let operator_span = iter.next_span();
             iter.consume();
             let left = result;
             let right = higher_precedence_fn(self, module, iter, ctx)?;
             let full_span = InputSpan::from_positions(
                 ctx.heap[left].full_span().begin,
                 ctx.heap[right].full_span().end,
             );
             result = ctx.heap.alloc_binary_expression(|this| BinaryExpression{
                 this, operator_span, full_span, left, operation, right,
                 parent: ExpressionParent::None,
                 type_index: -1,
             }).upcast();
+        }
         Ok(result)
+    }
     #[inline]
     fn consume_expression_list(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx, end_pos: Option<&mut InputPosition>
     ) -> Result<Vec<ExpressionId>, ParseError> {
         let mut section = self.expressions.start_section();
         consume_comma_separated(
             TokenKind::OpenParen, TokenKind::CloseParen, &module.source, iter, ctx,
             |_source, iter, ctx| self.consume_expression(module, iter, ctx),
             &mut section, "an expression", "a list of expressions", end_pos
         )?;
         Ok(section.into_vec())
+    }
+}
 /// Consumes polymorphic variables and throws them on the floor.
 fn consume_polymorphic_vars_spilled(source: &InputSource, iter: &mut TokenIter, _ctx: &mut PassCtx) -> Result<(), ParseError> {
     maybe_consume_comma_separated_spilled(
         TokenKind::OpenAngle, TokenKind::CloseAngle, source, iter, _ctx,
         |source, iter, _ctx| {
             consume_ident(source, iter)?;
             Ok(())
         }, "a polymorphic variable"
     )?;
     Ok(())
+}
 /// Consumes the parameter list to functions/components
 fn consume_parameter_list(
     parser: &mut ParserTypeParser, source: &InputSource, iter: &mut TokenIter,
     ctx: &mut PassCtx, target: &mut ScopedSection<VariableId>,
     scope: SymbolScope, definition_id: DefinitionId, allow_compiler_types: bool
 ) -> Result<(), ParseError> {
     consume_comma_separated(
         TokenKind::OpenParen, TokenKind::CloseParen, source, iter, ctx,
         |source, iter, ctx| {
             let poly_vars = ctx.heap[definition_id].poly_vars(); // Rust being rust, multiple lookups
             let parser_type = parser.consume_parser_type(
                 iter, &ctx.heap, source, &ctx.symbols, poly_vars, definition_id,
                 scope, false, allow_compiler_types, None
             )?;
             let identifier = consume_ident_interned(source, iter, ctx)?;
             let parameter_id = ctx.heap.alloc_variable(|this| Variable{
                 this,
                 kind: VariableKind::Parameter,
                 parser_type,
                 identifier,
                 relative_pos_in_parent: 0,
                 unique_id_in_scope: -1,
             });
             Ok(parameter_id)
         },
         target, "a parameter", "a parameter list", None
+    )
+}
@@ \ No newline at end of file @@

src/protocol/parser/pass_validation_linking.rs

➞

Show inline comments

@@ @@ -393,1346 +393,1347 @@ impl Visitor for PassValidationLinking { @@
         if !self.in_sync.is_invalid() {
             // Nested synchronous statement
             let old_sync_span = ctx.heap[self.in_sync].span;
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, cur_sync_span, "Illegal nested synchronous statement"
             ).with_info_str_at_span(
                 &ctx.module().source, old_sync_span, "It is nested in this synchronous statement"
             ));
+        }
         if self.proc_kind != ProcedureKind::Component {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, cur_sync_span,
                 "synchronous statements may only be used in components"
             ));
+        }
         // Synchronous statement implicitly moves to its block
         assign_then_erase_next_stmt!(self, ctx, id.upcast());
         // Visit block statement. Note that we explicitly push the scope here
         // (and the `visit_block_stmt` will also push, but without effect) to
         // ensure the scope contains the sync ID.
         let sync_body = ctx.heap[id].body;
         debug_assert!(self.in_sync.is_invalid());
         self.in_sync = id;
         let old_scope = self.push_scope(ctx, false, scope_id);
         self.visit_stmt(ctx, sync_body)?;
         self.pop_scope(old_scope);
         assign_and_replace_next_stmt!(self, ctx, end_sync_id.upcast());
         self.in_sync = SynchronousStatementId::new_invalid();
         Ok(())
+    }
     fn visit_fork_stmt(&mut self, ctx: &mut Ctx, id: ForkStatementId) -> VisitorResult {
         let fork_stmt = &ctx.heap[id];
         let end_fork_id = fork_stmt.end_fork;
         let left_body_id = fork_stmt.left_body;
         let right_body_id = fork_stmt.right_body;
         // Fork statements may only occur inside sync blocks
         if self.in_sync.is_invalid() {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, fork_stmt.span,
                 "Forking may only occur inside sync blocks"
             ));
+        }
         // Visit the respective bodies. Like the if statement, a fork statement
         // does not have a single static subsequent statement. It forks and then
         // each fork has a different next statement.
         assign_then_erase_next_stmt!(self, ctx, id.upcast());
         self.visit_stmt(ctx, left_body_id)?;
         assign_then_erase_next_stmt!(self, ctx, end_fork_id.upcast());
         if let Some(right_body_id) = right_body_id {
             self.visit_stmt(ctx, right_body_id)?;
             assign_then_erase_next_stmt!(self, ctx, end_fork_id.upcast());
+        }
         self.prev_stmt = end_fork_id.upcast();
         Ok(())
+    }
     fn visit_select_stmt(&mut self, ctx: &mut Ctx, id: SelectStatementId) -> VisitorResult {
         let select_stmt = &mut ctx.heap[id];
         select_stmt.relative_pos_in_parent = self.relative_pos_in_parent;
         self.relative_pos_in_parent += 1;
         let select_stmt = &ctx.heap[id];
         let end_select_id = select_stmt.end_select;
         // Select statements may only occur inside sync blocks
         if self.in_sync.is_invalid() {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, select_stmt.span,
                 "select statements may only occur inside sync blocks"
             ));
+        }
         if self.proc_kind != ProcedureKind::Component {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, select_stmt.span,
                 "select statements may only be used in components"
             ));
+        }
         // Visit the various arms in the select block
         let mut case_stmt_ids = self.statement_buffer.start_section();
         let mut case_scope_ids = self.scope_buffer.start_section();
         let num_cases = select_stmt.cases.len();
         for case in &select_stmt.cases {
             // We add them in pairs, so the subsequent for-loop retrieves in pairs
             case_stmt_ids.push(case.guard);
             case_stmt_ids.push(case.body);
             case_scope_ids.push(case.scope);
+        }
         assign_then_erase_next_stmt!(self, ctx, id.upcast());
         for index in 0..num_cases {
             let base_index = 2 * index;
             let guard_id     = case_stmt_ids[base_index];
             let case_body_id = case_stmt_ids[base_index + 1];
             let case_scope_id = case_scope_ids[index];
             // The guard statement ends up belonging to the block statement
             // following the arm. The reason we parse it separately is to
             // extract all of the "get" calls.
             let old_scope = self.push_scope(ctx, false, case_scope_id);
             // Visit the guard of this arm
             debug_assert!(self.in_select_guard.is_invalid());
             self.in_select_guard = id;
             self.in_select_arm = index as u32;
             self.visit_stmt(ctx, guard_id)?;
             self.in_select_guard = SelectStatementId::new_invalid();
             // Visit the code associated with the guard
             self.relative_pos_in_parent += 1;
             self.visit_stmt(ctx, case_body_id)?;
             self.pop_scope(old_scope);
             // Link up last statement in block to EndSelect
             assign_then_erase_next_stmt!(self, ctx, end_select_id.upcast());
+        }
         self.in_select_guard = SelectStatementId::new_invalid();
         self.prev_stmt = end_select_id.upcast();
         Ok(())
+    }
     fn visit_return_stmt(&mut self, ctx: &mut Ctx, id: ReturnStatementId) -> VisitorResult {
         // Check if "return" occurs within a function
         let stmt = &ctx.heap[id];
         if self.proc_kind != ProcedureKind::Function {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, stmt.span,
                 "return statements may only appear in function bodies"
             ));
+        }
         // If here then we are within a function
         assign_then_erase_next_stmt!(self, ctx, id.upcast());
         debug_assert_eq!(self.expr_parent, ExpressionParent::None);
         debug_assert_eq!(ctx.heap[id].expressions.len(), 1);
         self.expr_parent = ExpressionParent::Return(id);
         self.visit_expr(ctx, ctx.heap[id].expressions[0])?;
         self.expr_parent = ExpressionParent::None;
         Ok(())
+    }
     fn visit_goto_stmt(&mut self, ctx: &mut Ctx, id: GotoStatementId) -> VisitorResult {
         self.control_flow_stmts.push(ControlFlowStatement{
             in_sync: self.in_sync,
             in_while: self.in_while,
             in_scope: self.cur_scope,
             statement: id.upcast(),
         });
         assign_then_erase_next_stmt!(self, ctx, id.upcast());
         Ok(())
+    }
     fn visit_new_stmt(&mut self, ctx: &mut Ctx, id: NewStatementId) -> VisitorResult {
         // Make sure the new statement occurs inside a component
         if self.proc_kind != ProcedureKind::Component {
             let new_stmt = &ctx.heap[id];
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, new_stmt.span,
                 "instantiating components may only be done in components"
             ));
+        }
         // Recurse into call expression (which will check the expression parent
         // to ensure that the "new" statment instantiates a component)
         let call_expr_id = ctx.heap[id].expression;
         assign_and_replace_next_stmt!(self, ctx, id.upcast());
         debug_assert_eq!(self.expr_parent, ExpressionParent::None);
         self.expr_parent = ExpressionParent::New(id);
         self.visit_call_expr(ctx, call_expr_id)?;
         self.expr_parent = ExpressionParent::None;
         Ok(())
+    }
     fn visit_expr_stmt(&mut self, ctx: &mut Ctx, id: ExpressionStatementId) -> VisitorResult {
         let expr_id = ctx.heap[id].expression;
         assign_and_replace_next_stmt!(self, ctx, id.upcast());
         debug_assert_eq!(self.expr_parent, ExpressionParent::None);
         self.expr_parent = ExpressionParent::ExpressionStmt(id);
         self.visit_expr(ctx, expr_id)?;
         self.expr_parent = ExpressionParent::None;
         Ok(())
+    }
     //--------------------------------------------------------------------------
     // Expression visitors
     //--------------------------------------------------------------------------
     fn visit_assignment_expr(&mut self, ctx: &mut Ctx, id: AssignmentExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         let assignment_expr = &mut ctx.heap[id];
         // Although we call assignment an expression to simplify the compiler's
         // code (mainly typechecking), we disallow nested use in expressions
         match self.expr_parent {
             // Look at us: lying through our teeth while providing error messages.
             ExpressionParent::Memory(_) => {},
             ExpressionParent::ExpressionStmt(_) => {},
             _ => {
                 let assignment_span = assignment_expr.full_span;
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module().source, assignment_span,
                     "assignments are statements, and cannot be used in expressions"
                 ))
             },
+        }
         let left_expr_id = assignment_expr.left;
         let right_expr_id = assignment_expr.right;
         let old_expr_parent = self.expr_parent;
         assignment_expr.parent = old_expr_parent;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
         self.must_be_assignable = Some(assignment_expr.operator_span);
         self.visit_expr(ctx, left_expr_id)?;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
         self.must_be_assignable = None;
         self.visit_expr(ctx, right_expr_id)?;
         self.expr_parent = old_expr_parent;
         Ok(())
+    }
     fn visit_binding_expr(&mut self, ctx: &mut Ctx, id: BindingExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         // Check for valid context of binding expression
         if let Some(span) = self.must_be_assignable {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, span, "cannot assign to the result from a binding expression"
             ));
+        }
         if self.in_test_expr.is_invalid() {
             let binding_expr = &ctx.heap[id];
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, binding_expr.full_span,
                 "binding expressions can only be used inside the testing expression of 'if' and 'while' statements"
             ));
+        }
         if !self.in_binding_expr.is_invalid() {
             let binding_expr = &ctx.heap[id];
             let previous_expr = &ctx.heap[self.in_binding_expr];
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, binding_expr.full_span,
                 "nested binding expressions are not allowed"
             ).with_info_str_at_span(
                 &ctx.module().source, previous_expr.operator_span,
                 "the outer binding expression is found here"
             ));
+        }
         let mut seeking_parent = self.expr_parent;
         loop {
             // Perform upward search to make sure only LogicalAnd is applied to
             // the binding expression
             let valid = match seeking_parent {
                 ExpressionParent::If(_) | ExpressionParent::While(_) => {
                     // Every parent expression (if any) were LogicalAnd.
                     break;
+                }
                 ExpressionParent::Expression(parent_id, _) => {
                     let parent_expr = &ctx.heap[parent_id];
                     match parent_expr {
                         Expression::Binary(parent_expr) => {
                             // Set new parent to continue the search. Otherwise
                             // halt and provide an error using the current
                             // parent.
                             if parent_expr.operation == BinaryOperator::LogicalAnd {
                                 seeking_parent = parent_expr.parent;
                                 true
                             } else {
                                 false
+                            }
                         },
                         _ => false,
+                    }
                 },
                 _ => unreachable!(), // nested under if/while, so always expressions as parents
             };
             if !valid {
                 let binding_expr = &ctx.heap[id];
                 let parent_expr = &ctx.heap[seeking_parent.as_expression()];
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module().source, binding_expr.full_span,
                     "only the logical-and operator (&&) may be applied to binding expressions"
                 ).with_info_str_at_span(
                     &ctx.module().source, parent_expr.operation_span(),
                     "this was the disallowed operation applied to the result from a binding expression"
                 ));
+            }
+        }
         // Perform all of the index/parent assignment magic
         let binding_expr = &mut ctx.heap[id];
         let old_expr_parent = self.expr_parent;
         binding_expr.parent = old_expr_parent;
         self.in_binding_expr = id;
         // Perform preliminary check on children: binding expressions only make
         // sense if the left hand side is just a variable expression, or if it
         // is a literal of some sort. The typechecker will take care of the rest
         let bound_to_id = binding_expr.bound_to;
         let bound_from_id = binding_expr.bound_from;
         match &ctx.heap[bound_to_id] {
             // Variables may not be binding variables, and literals may
             // actually not contain binding variables. But in that case we just
             // perform an equality check.
             Expression::Variable(_) => {}
             Expression::Literal(_) => {},
             _ => {
                 let binding_expr = &ctx.heap[id];
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module().source, binding_expr.operator_span,
                     "the left hand side of a binding expression may only be a variable or a literal expression"
                 ));
             },
+        }
         // Visit the children themselves
         self.in_binding_expr_lhs = true;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
         self.visit_expr(ctx, bound_to_id)?;
         self.in_binding_expr_lhs = false;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
         self.visit_expr(ctx, bound_from_id)?;
         self.expr_parent = old_expr_parent;
         self.in_binding_expr = BindingExpressionId::new_invalid();
         Ok(())
+    }
     fn visit_conditional_expr(&mut self, ctx: &mut Ctx, id: ConditionalExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         let conditional_expr = &mut ctx.heap[id];
         if let Some(span) = self.must_be_assignable {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, span, "cannot assign to the result from a conditional expression"
             ))
+        }
         let test_expr_id = conditional_expr.test;
         let true_expr_id = conditional_expr.true_expression;
         let false_expr_id = conditional_expr.false_expression;
         let old_expr_parent = self.expr_parent;
         conditional_expr.parent = old_expr_parent;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
         self.visit_expr(ctx, test_expr_id)?;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
         self.visit_expr(ctx, true_expr_id)?;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 2);
         self.visit_expr(ctx, false_expr_id)?;
         self.expr_parent = old_expr_parent;
         Ok(())
+    }
     fn visit_binary_expr(&mut self, ctx: &mut Ctx, id: BinaryExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         let binary_expr = &mut ctx.heap[id];
         if let Some(span) = self.must_be_assignable {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, span, "cannot assign to the result from a binary expression"
             ))
+        }
         let left_expr_id = binary_expr.left;
         let right_expr_id = binary_expr.right;
         let old_expr_parent = self.expr_parent;
         binary_expr.parent = old_expr_parent;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
         self.visit_expr(ctx, left_expr_id)?;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
         self.visit_expr(ctx, right_expr_id)?;
         self.expr_parent = old_expr_parent;
         Ok(())
+    }
     fn visit_unary_expr(&mut self, ctx: &mut Ctx, id: UnaryExpressionId) -> VisitorResult {
         let unary_expr = &mut ctx.heap[id];
         let expr_id = unary_expr.expression;
         if let Some(span) = self.must_be_assignable {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, span, "cannot assign to the result from a unary expression"
             ))
+        }
         let old_expr_parent = self.expr_parent;
         unary_expr.parent = old_expr_parent;
         self.expr_parent = ExpressionParent::Expression(id.upcast(), 0);
         self.visit_expr(ctx, expr_id)?;
         self.expr_parent = old_expr_parent;
         Ok(())
+    }
     fn visit_indexing_expr(&mut self, ctx: &mut Ctx, id: IndexingExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         let indexing_expr = &mut ctx.heap[id];
         let subject_expr_id = indexing_expr.subject;
         let index_expr_id = indexing_expr.index;
         let old_expr_parent = self.expr_parent;
         indexing_expr.parent = old_expr_parent;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
         self.visit_expr(ctx, subject_expr_id)?;
         let old_assignable = self.must_be_assignable.take();
         self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
         self.visit_expr(ctx, index_expr_id)?;
         self.must_be_assignable = old_assignable;
         self.expr_parent = old_expr_parent;
         Ok(())
+    }
     fn visit_slicing_expr(&mut self, ctx: &mut Ctx, id: SlicingExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         let slicing_expr = &mut ctx.heap[id];
         if let Some(span) = self.must_be_assignable {
             // TODO: @Slicing
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, span, "assignment to slices should be valid in the final language, but is currently not implemented"
             ));
+        }
         let subject_expr_id = slicing_expr.subject;
         let from_expr_id = slicing_expr.from_index;
         let to_expr_id = slicing_expr.to_index;
         let old_expr_parent = self.expr_parent;
         slicing_expr.parent = old_expr_parent;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
         self.visit_expr(ctx, subject_expr_id)?;
         let old_assignable = self.must_be_assignable.take();
         self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
         self.visit_expr(ctx, from_expr_id)?;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 2);
         self.visit_expr(ctx, to_expr_id)?;
         self.must_be_assignable = old_assignable;
         self.expr_parent = old_expr_parent;
         Ok(())
+    }
     fn visit_select_expr(&mut self, ctx: &mut Ctx, id: SelectExpressionId) -> VisitorResult {
         let select_expr = &mut ctx.heap[id];
         let expr_id = select_expr.subject;
         let old_expr_parent = self.expr_parent;
         select_expr.parent = old_expr_parent;
         self.expr_parent = ExpressionParent::Expression(id.upcast(), 0);
         self.visit_expr(ctx, expr_id)?;
         self.expr_parent = old_expr_parent;
         Ok(())
+    }
     fn visit_literal_expr(&mut self, ctx: &mut Ctx, id: LiteralExpressionId) -> VisitorResult {
         let literal_expr = &mut ctx.heap[id];
         let old_expr_parent = self.expr_parent;
         literal_expr.parent = old_expr_parent;
         if let Some(span) = self.must_be_assignable {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, span, "cannot assign to a literal expression"
             ))
+        }
         match &mut literal_expr.value {
             Literal::Null | Literal::True | Literal::False |
             Literal::Character(_) | Literal::Bytestring(_) | Literal::String(_) |
             Literal::Integer(_) => {
                 // Just the parent has to be set, done above
             },
             Literal::Struct(literal) => {
                 let upcast_id = id.upcast();
                 // Retrieve type definition
                 let type_definition = ctx.types.get_base_definition(&literal.definition).unwrap();
                 let struct_definition = type_definition.definition.as_struct();
                 // Make sure all fields are specified, none are specified twice
                 // and all fields exist on the struct definition
                 let mut specified = Vec::new(); // TODO: @performance
                 specified.resize(struct_definition.fields.len(), false);
                 for field in &mut literal.fields {
                     // Find field in the struct definition
                     let field_idx = struct_definition.fields.iter().position(|v| v.identifier == field.identifier);
                     if field_idx.is_none() {
                         let field_span = field.identifier.span;
                         let literal = ctx.heap[id].value.as_struct();
                         let ast_definition = &ctx.heap[literal.definition];
                         return Err(ParseError::new_error_at_span(
                             &ctx.module().source, field_span, format!(
                                 "This field does not exist on the struct '{}'",
                                 ast_definition.identifier().value.as_str()
+                            )
                         ));
+                    }
                     field.field_idx = field_idx.unwrap();
                     // Check if specified more than once
                     if specified[field.field_idx] {
                         let field_span = field.identifier.span;
                         return Err(ParseError::new_error_str_at_span(
                             &ctx.module().source, field_span,
                             "This field is specified more than once"
                         ));
+                    }
                     specified[field.field_idx] = true;
+                }
                 if !specified.iter().all(|v| *v) {
                     // Some fields were not specified
                     let mut not_specified = String::new();
                     let mut num_not_specified = 0;
                     for (def_field_idx, is_specified) in specified.iter().enumerate() {
                         if !is_specified {
                             if !not_specified.is_empty() { not_specified.push_str(", ") }
                             let field_ident = &struct_definition.fields[def_field_idx].identifier;
                             not_specified.push_str(field_ident.value.as_str());
                             num_not_specified += 1;
+                        }
+                    }
                     debug_assert!(num_not_specified > 0);
                     let msg = if num_not_specified == 1 {
                         format!("not all fields are specified, '{}' is missing", not_specified)
                     } else {
                         format!("not all fields are specified, [{}] are missing", not_specified)
                     };
                     let literal_span = literal.parser_type.full_span;
                     return Err(ParseError::new_error_at_span(
                         &ctx.module().source, literal_span, msg
                     ));
+                }
                 // Need to traverse fields expressions in struct and evaluate
                 // the poly args
                 let mut expr_section = self.expression_buffer.start_section();
                 for field in &literal.fields {
                     expr_section.push(field.value);
+                }
                 for expr_idx in 0..expr_section.len() {
                     let expr_id = expr_section[expr_idx];
                     self.expr_parent = ExpressionParent::Expression(upcast_id, expr_idx as u32);
                     self.visit_expr(ctx, expr_id)?;
+                }
                 expr_section.forget();
             },
             Literal::Enum(literal) => {
                 // Make sure the variant exists
                 let type_definition = ctx.types.get_base_definition(&literal.definition).unwrap();
                 let enum_definition = type_definition.definition.as_enum();
                 let variant_idx = enum_definition.variants.iter().position(|v| {
                     v.identifier == literal.variant
                 });
                 if variant_idx.is_none() {
                     let literal = ctx.heap[id].value.as_enum();
                     let ast_definition = ctx.heap[literal.definition].as_enum();
                     return Err(ParseError::new_error_at_span(
                         &ctx.module().source, literal.parser_type.full_span, format!(
                             "the variant '{}' does not exist on the enum '{}'",
                             literal.variant.value.as_str(), ast_definition.identifier.value.as_str()
+                        )
                     ));
+                }
                 literal.variant_idx = variant_idx.unwrap();
             },
             Literal::Union(literal) => {
                 // Make sure the variant exists
                 let type_definition = ctx.types.get_base_definition(&literal.definition).unwrap();
                 let union_definition = type_definition.definition.as_union();
                 let variant_idx = union_definition.variants.iter().position(|v| {
                     v.identifier == literal.variant
                 });
                 if variant_idx.is_none() {
                     let literal = ctx.heap[id].value.as_union();
                     let ast_definition = ctx.heap[literal.definition].as_union();
                     return Err(ParseError::new_error_at_span(
                         &ctx.module().source, literal.parser_type.full_span, format!(
                             "the variant '{}' does not exist on the union '{}'",
                             literal.variant.value.as_str(), ast_definition.identifier.value.as_str()
+                        )
                     ));
+                }
                 literal.variant_idx = variant_idx.unwrap();
                 // Make sure the number of specified values matches the expected
                 // number of embedded values in the union variant.
                 let union_variant = &union_definition.variants[literal.variant_idx];
                 if union_variant.embedded.len() != literal.values.len() {
                     let literal = ctx.heap[id].value.as_union();
                     let ast_definition = ctx.heap[literal.definition].as_union();
                     return Err(ParseError::new_error_at_span(
                         &ctx.module().source, literal.parser_type.full_span, format!(
                             "The variant '{}' of union '{}' expects {} embedded values, but {} were specified",
                             literal.variant.value.as_str(), ast_definition.identifier.value.as_str(),
                             union_variant.embedded.len(), literal.values.len()
                         ),
                     ))
+                }
                 // Traverse embedded values of union (if any) and evaluate the
                 // polymorphic arguments
                 let upcast_id = id.upcast();
                 let mut expr_section = self.expression_buffer.start_section();
                 for value in &literal.values {
                     expr_section.push(*value);
+                }
                 for expr_idx in 0..expr_section.len() {
                     let expr_id = expr_section[expr_idx];
                     self.expr_parent = ExpressionParent::Expression(upcast_id, expr_idx as u32);
                     self.visit_expr(ctx, expr_id)?;
+                }
                 expr_section.forget();
             },
             Literal::Array(literal) | Literal::Tuple(literal) => {
                 // Visit all expressions in the array
                 let upcast_id = id.upcast();
                 let expr_section = self.expression_buffer.start_section_initialized(literal);
                 for expr_idx in 0..expr_section.len() {
                     let expr_id = expr_section[expr_idx];
                     self.expr_parent = ExpressionParent::Expression(upcast_id, expr_idx as u32);
                     self.visit_expr(ctx, expr_id)?;
+                }
                 expr_section.forget();
+            }
+        }
         self.expr_parent = old_expr_parent;
         Ok(())
+    }
     fn visit_cast_expr(&mut self, ctx: &mut Ctx, id: CastExpressionId) -> VisitorResult {
         let cast_expr = &mut ctx.heap[id];
         if let Some(span) = self.must_be_assignable {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, span, "cannot assign to the result from a cast expression"
             ))
+        }
         let upcast_id = id.upcast();
         let old_expr_parent = self.expr_parent;
         cast_expr.parent = old_expr_parent;
         // Recurse into the thing that we're casting
         self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
         let subject_id = cast_expr.subject;
         self.visit_expr(ctx, subject_id)?;
         self.expr_parent = old_expr_parent;
         Ok(())
+    }
     fn visit_call_expr(&mut self, ctx: &mut Ctx, id: CallExpressionId) -> VisitorResult {
         let call_expr = &ctx.heap[id];
         if let Some(span) = self.must_be_assignable {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module().source, span, "cannot assign to the result from a call expression"
             ))
+        }
         // Check whether the method is allowed to be called within the code's
         // context (in sync, definition type, etc.)
         let mut expecting_wrapping_new_stmt = false;
         let mut expecting_wrapping_sync_stmt = false;
         let mut expecting_no_select_stmt = false;
         match call_expr.method {
             Method::Get => {
                 expecting_wrapping_sync_stmt = true;
                 if !self.in_select_guard.is_invalid() {
                     // In a select guard. Take the argument (i.e. the port we're
                     // retrieving from) and add it to the list of involved ports
                     // of the guard
                     if call_expr.arguments.len() == 1 {
                         // We're checking the number of arguments later, for now
                         // assume it is correct.
                         let argument = call_expr.arguments[0];
                         let select_stmt = &mut ctx.heap[self.in_select_guard];
                         let select_case = &mut select_stmt.cases[self.in_select_arm as usize];
                         select_case.involved_ports.push((id, argument));
+                    }
+                }
             },
             Method::Put => {
                 expecting_wrapping_sync_stmt = true;
                 expecting_no_select_stmt = true;
             },
             Method::Fires => {
                 expecting_wrapping_sync_stmt = true;
             },
             Method::Create => {},
             Method::Length => {},
             Method::Assert => {
                 expecting_wrapping_sync_stmt = true;
                 expecting_no_select_stmt = true;
                 if self.proc_kind == ProcedureKind::Function {
                     let call_span = call_expr.func_span;
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module().source, call_span,
                         "assert statement may only occur in components"
                     ));
+                }
             },
             Method::Print => {},
             Method::SelectStart
             | Method::SelectRegisterCasePort
             | Method::SelectWait => unreachable!(), // not usable by programmer directly
             Method::ComponentRandomU32
             | Method::ComponentTcpClient => {
             | Method::ComponentTcpClient
             | Method::ComponentTcpListener => {
                 expecting_wrapping_new_stmt = true;
             },
             Method::UserFunction => {}
             Method::UserComponent => {
                 expecting_wrapping_new_stmt = true;
             },
+        }
         let call_expr = &mut ctx.heap[id];
         fn get_span_and_name<'a>(ctx: &'a Ctx, id: CallExpressionId) -> (InputSpan, String) {
             let call = &ctx.heap[id];
             let span = call.func_span;
             let name = String::from_utf8_lossy(ctx.module().source.section_at_span(span)).to_string();
             return (span, name);
+        }
         if expecting_wrapping_sync_stmt {
             if self.in_sync.is_invalid() {
                 let (call_span, func_name) = get_span_and_name(ctx, id);
                 return Err(ParseError::new_error_at_span(
                     &ctx.module().source, call_span,
                     format!("a call to '{}' may only occur inside synchronous blocks", func_name)
                 ))
+            }
+        }
         if expecting_no_select_stmt {
             if !self.in_select_guard.is_invalid() {
                 let (call_span, func_name) = get_span_and_name(ctx, id);
                 return Err(ParseError::new_error_at_span(
                     &ctx.module().source, call_span,
                     format!("a call to '{}' may not occur in a select statement's guard", func_name)
                 ));
+            }
+        }
         if expecting_wrapping_new_stmt {
             if !self.expr_parent.is_new() {
                 let call_span = call_expr.func_span;
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module().source, call_span,
                     "cannot call a component, it can only be instantiated by using 'new'"
                 ));
+            }
         } else {
             if self.expr_parent.is_new() {
                 let call_span = call_expr.func_span;
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module().source, call_span,
                     "only components can be instantiated, this is a function"
                 ));
+            }
+        }
         // Check the number of arguments
         let call_definition = ctx.types.get_base_definition(&call_expr.procedure.upcast()).unwrap();
         let num_expected_args = match &call_definition.definition {
             DefinedTypeVariant::Procedure(definition) => definition.arguments.len(),
             _ => unreachable!(),
         };
         let num_provided_args = call_expr.arguments.len();
         if num_provided_args != num_expected_args {
             let argument_text = if num_expected_args == 1 { "argument" } else { "arguments" };
             let call_span = call_expr.full_span;
             return Err(ParseError::new_error_at_span(
                 &ctx.module().source, call_span, format!(
                     "expected {} {}, but {} were provided",
                     num_expected_args, argument_text, num_provided_args
+                )
             ));
+        }
         // Recurse into all of the arguments and set the expression's parent
         let upcast_id = id.upcast();
         let section = self.expression_buffer.start_section_initialized(&call_expr.arguments);
         let old_expr_parent = self.expr_parent;
         call_expr.parent = old_expr_parent;
         for arg_expr_idx in 0..section.len() {
             let arg_expr_id = section[arg_expr_idx];
             self.expr_parent = ExpressionParent::Expression(upcast_id, arg_expr_idx as u32);
             self.visit_expr(ctx, arg_expr_id)?;
+        }
         section.forget();
         self.expr_parent = old_expr_parent;
         Ok(())
+    }
     fn visit_variable_expr(&mut self, ctx: &mut Ctx, id: VariableExpressionId) -> VisitorResult {
         let var_expr = &ctx.heap[id];
         // Check if declaration was already resolved (this occurs for the
         // variable expr that is on the LHS of the assignment expr that is
         // associated with a variable declaration)
         let mut variable_id = var_expr.declaration;
         let mut is_binding_target = false;
         // Otherwise try to find it
         if variable_id.is_none() {
             variable_id = self.find_variable(ctx, self.relative_pos_in_parent, &var_expr.identifier);
+        }
         // Otherwise try to see if is a variable introduced by a binding expr
         let variable_id = if let Some(variable_id) = variable_id {
             variable_id
         } else {
             if self.in_binding_expr.is_invalid() || !self.in_binding_expr_lhs {
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module().source, var_expr.identifier.span, "unresolved variable"
                 ));
+            }
             // This is a binding variable, but it may only appear in very
             // specific locations.
             let is_valid_binding = match self.expr_parent {
                 ExpressionParent::Expression(expr_id, idx) => {
                     match &ctx.heap[expr_id] {
                         Expression::Binding(_binding_expr) => {
                             // Nested binding is disallowed, and because of
                             // the check above we know we're directly at the
                             // LHS of the binding expression
                             debug_assert_eq!(_binding_expr.this, self.in_binding_expr);
                             debug_assert_eq!(idx, 0);
                             true
+                        }
                         Expression::Literal(_lit_expr) => {
                             // Only struct, unions, tuples and arrays can
                             // have subexpressions, so we're always fine
                             dbg_code!({
                                 match _lit_expr.value {
                                     Literal::Struct(_) | Literal::Union(_) | Literal::Array(_) | Literal::Tuple(_) => {},
                                     _ => unreachable!(),
+                                }
                             });
                             true
                         },
                         _ => false,
+                    }
                 },
                 _ => {
                     false
+                }
             };
             if !is_valid_binding {
                 let binding_expr = &ctx.heap[self.in_binding_expr];
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module().source, var_expr.identifier.span,
                     "illegal location for binding variable: binding variables may only be nested under a binding expression, or a struct, union or array literal"
                 ).with_info_at_span(
                     &ctx.module().source, binding_expr.operator_span, format!(
                         "'{}' was interpreted as a binding variable because the variable is not declared and it is nested under this binding expression",
                         var_expr.identifier.value.as_str()
+                    )
                 ));
+            }
             // By now we know that this is a valid binding expression. Given
             // that a binding expression must be nested under an if/while
             // statement, we now add the variable to the scope associated with
             // that statement.
             let bound_identifier = var_expr.identifier.clone();
             let bound_variable_id = ctx.heap.alloc_variable(|this| Variable {
                 this,
                 kind: VariableKind::Binding,
                 parser_type: ParserType {
                     elements: vec![ParserTypeElement {
                         element_span: bound_identifier.span,
                         variant: ParserTypeVariant::Inferred
                     }],
                     full_span: bound_identifier.span
                 },
                 identifier: bound_identifier,
                 relative_pos_in_parent: 0,
                 unique_id_in_scope: -1,
             });
             let scope_id = match &ctx.heap[self.in_test_expr] {
                 Statement::If(stmt) => stmt.true_case.scope,
                 Statement::While(stmt) => stmt.scope,
                 _ => unreachable!(),
             };
             self.checked_at_single_scope_add_local(ctx, scope_id, -1, bound_variable_id)?; // add at -1 such that first statement can find the variable if needed
             is_binding_target = true;
             bound_variable_id
         };
         let var_expr = &mut ctx.heap[id];
         var_expr.declaration = Some(variable_id);
         var_expr.used_as_binding_target = is_binding_target;
         var_expr.parent = self.expr_parent;
         Ok(())
+    }
+}
 impl PassValidationLinking {
     //--------------------------------------------------------------------------
     // Special traversal
     //--------------------------------------------------------------------------
     /// Pushes a new scope associated with a particular statement. If that
     /// statement already has an associated scope (i.e. scope associated with
     /// sync statement or select statement's arm) then we won't do anything.
     /// In all cases the caller must call `pop_statement_scope` with the scope
     /// and relative scope position returned by this function.
     fn push_scope(&mut self, ctx: &mut Ctx, is_top_level_scope: bool, pushed_scope_id: ScopeId) -> (ScopeId, i32) {
         // Set the properties of the pushed scope (it is already created during
         // AST construction, but most values are not yet set to their correct
         // values)
         let old_scope_id = self.cur_scope;
         let scope = &mut ctx.heap[pushed_scope_id];
         if !is_top_level_scope {
             scope.parent = Some(old_scope_id);
+        }
         scope.relative_pos_in_parent = self.relative_pos_in_parent;
         let old_relative_pos = self.relative_pos_in_parent;
         self.relative_pos_in_parent = 0;
         // Link up scopes
         if !is_top_level_scope {
             let old_scope = &mut ctx.heap[old_scope_id];
             old_scope.nested.push(pushed_scope_id);
+        }
         // Set as current traversal scope, then return old scope
         self.cur_scope = pushed_scope_id;
         return (old_scope_id, old_relative_pos)
+    }
     fn pop_scope(&mut self, scope_to_restore: (ScopeId, i32)) {
         self.cur_scope = scope_to_restore.0;
         self.relative_pos_in_parent = scope_to_restore.1;
+    }
     fn resolve_pending_control_flow_targets(&mut self, ctx: &mut Ctx) -> Result<(), ParseError> {
         for entry in &self.control_flow_stmts {
             let stmt = &ctx.heap[entry.statement];
             match stmt {
                 Statement::Break(stmt) => {
                     let stmt_id = stmt.this;
                     let target_while_id = Self::resolve_break_or_continue_target(ctx, entry, stmt.span, &stmt.label)?;
                     let target_while_stmt = &ctx.heap[target_while_id];
                     let target_end_while_id = target_while_stmt.end_while;
                     debug_assert!(!target_end_while_id.is_invalid());
                     let break_stmt = &mut ctx.heap[stmt_id];
                     break_stmt.target = target_end_while_id;
                 },
                 Statement::Continue(stmt) => {
                     let stmt_id = stmt.this;
                     let target_while_id = Self::resolve_break_or_continue_target(ctx, entry, stmt.span, &stmt.label)?;
                     let continue_stmt = &mut ctx.heap[stmt_id];
                     continue_stmt.target = target_while_id;
                 },
                 Statement::Goto(stmt) => {
                     let stmt_id = stmt.this;
                     let target_id = Self::find_label(entry.in_scope, ctx, &stmt.label)?;
                     let target_stmt = &ctx.heap[target_id];
                     if entry.in_sync != target_stmt.in_sync {
                         // Nested sync not allowed. And goto can only go to
                         // outer scopes, so we must be escaping from a sync.
                         debug_assert!(target_stmt.in_sync.is_invalid());    // target not in sync
                         debug_assert!(!entry.in_sync.is_invalid()); // but the goto is in sync
                         let goto_stmt = &ctx.heap[stmt_id];
                         let sync_stmt = &ctx.heap[entry.in_sync];
                         return Err(
                             ParseError::new_error_str_at_span(&ctx.module().source, goto_stmt.span, "goto may not escape the surrounding synchronous block")
                             .with_info_str_at_span(&ctx.module().source, target_stmt.label.span, "this is the target of the goto statement")
                             .with_info_str_at_span(&ctx.module().source, sync_stmt.span, "which will jump past this statement")
                         );
+                    }
                     let goto_stmt = &mut ctx.heap[stmt_id];
                     goto_stmt.target = target_id;
                 },
                 _ => unreachable!("cannot resolve control flow target for {:?}", stmt),
+            }
+        }
         return Ok(())
+    }
     //--------------------------------------------------------------------------
     // Utilities
     //--------------------------------------------------------------------------
     /// Adds a local variable to the current scope. It will also annotate the
     /// `Local` in the AST with its relative position in the block.
     fn checked_add_local(&mut self, ctx: &mut Ctx, target_scope_id: ScopeId, target_relative_pos: i32, new_variable_id: VariableId) -> Result<(), ParseError> {
         let new_variable = &ctx.heap[new_variable_id];
         // We immediately go to the parent scope. We check the target scope
         // in the call at the end. That is also where we check for collisions
         // with symbols.
         let mut scope = &ctx.heap[target_scope_id];
         let mut cur_relative_pos = scope.relative_pos_in_parent;
         while let Some(scope_parent_id) = scope.parent {
             scope = &ctx.heap[scope_parent_id];
             // Check for collisions
             for variable_id in scope.variables.iter().copied() {
                 let existing_variable = &ctx.heap[variable_id];
                 if existing_variable.identifier == new_variable.identifier &&
                     existing_variable.this != new_variable_id &&
                     cur_relative_pos >= existing_variable.relative_pos_in_parent {
                     return Err(
                         ParseError::new_error_str_at_span(
                             &ctx.module().source, new_variable.identifier.span, "Local variable name conflicts with another variable"
                         ).with_info_str_at_span(
                             &ctx.module().source, existing_variable.identifier.span, "Previous variable is found here"
+                        )
                     );
+                }
+            }
             cur_relative_pos = scope.relative_pos_in_parent;
+        }
         // No collisions in any of the parent scope, attempt to add to scope
         self.checked_at_single_scope_add_local(ctx, target_scope_id, target_relative_pos, new_variable_id)
+    }
     /// Adds a local variable to the specified scope. Will check the specified
     /// scope for variable conflicts and the symbol table for global conflicts.
     /// Will NOT check parent scopes of the specified scope.
     fn checked_at_single_scope_add_local(
         &mut self, ctx: &mut Ctx, scope_id: ScopeId, relative_pos: i32, new_variable_id: VariableId
     ) -> Result<(), ParseError> {
         // Check the symbol table for conflicts
+        {
             let cur_scope = SymbolScope::Definition(self.proc_id.upcast());
             let ident = &ctx.heap[new_variable_id].identifier;
             if let Some(symbol) = ctx.symbols.get_symbol_by_name(cur_scope, &ident.value.as_bytes()) {
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module().source, ident.span,
                     "local variable declaration conflicts with symbol"
                 ).with_info_str_at_span(
                     &ctx.module().source, symbol.variant.span_of_introduction(&ctx.heap), "the conflicting symbol is introduced here"
                 ));
+            }
+        }
         // Check the specified scope for conflicts
         let new_variable = &ctx.heap[new_variable_id];
         let scope = &ctx.heap[scope_id];
         for variable_id in scope.variables.iter().copied() {
             let old_variable = &ctx.heap[variable_id];
             if new_variable.this != old_variable.this &&
                 // relative_pos >= other_local.relative_pos_in_block &&
                 new_variable.identifier == old_variable.identifier {
                 // Collision
                 return Err(
                     ParseError::new_error_str_at_span(
                         &ctx.module().source, new_variable.identifier.span, "Local variable name conflicts with another variable"
                     ).with_info_str_at_span(
                         &ctx.module().source, old_variable.identifier.span, "Previous variable is found here"
+                    )
                 );
+            }
+        }
         // No collisions
         let scope = &mut ctx.heap[scope_id];
         scope.variables.push(new_variable_id);
         let variable = &mut ctx.heap[new_variable_id];
         variable.relative_pos_in_parent = relative_pos;
         Ok(())
+    }
     /// Finds a variable in the visitor's scope that must appear before the
     /// specified relative position within that block.
     fn find_variable(&self, ctx: &Ctx, mut relative_pos: i32, identifier: &Identifier) -> Option<VariableId> {
         let mut scope_id = self.cur_scope;
         loop {
             // Check if we can find the variable in the current scope
             let scope = &ctx.heap[scope_id];
             for variable_id in scope.variables.iter().copied() {
                 let variable = &ctx.heap[variable_id];
                 if variable.relative_pos_in_parent < relative_pos && identifier == &variable.identifier {
                     return Some(variable_id);
+                }
+            }
             // Could not find variable, move to parent scope and try again
             if scope.parent.is_none() {
                 return None;
+            }
             scope_id = scope.parent.unwrap();
             relative_pos = scope.relative_pos_in_parent;
+        }
+    }
     /// Adds a particular label to the current scope. Will return an error if
     /// there is another label with the same name visible in the current scope.
     fn checked_add_label(&mut self, ctx: &mut Ctx, relative_pos: i32, in_sync: SynchronousStatementId, new_label_id: LabeledStatementId) -> Result<(), ParseError> {
         // Make sure label is not defined within the current scope or any of the
         // parent scope.
         let new_label = &mut ctx.heap[new_label_id];
         new_label.relative_pos_in_parent = relative_pos;
         new_label.in_sync = in_sync;
         let new_label = &ctx.heap[new_label_id];
         let mut scope_id = self.cur_scope;
         loop {
             let scope = &ctx.heap[scope_id];
             for existing_label_id in scope.labels.iter().copied() {
                 let existing_label = &ctx.heap[existing_label_id];
                 if existing_label.label == new_label.label {
                     // Collision
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module().source, new_label.label.span, "label name is used more than once"
                     ).with_info_str_at_span(
                         &ctx.module().source, existing_label.label.span, "the other label is found here"
                     ));
+                }
+            }
             if scope.parent.is_none() {
                 break;
+            }
             scope_id = scope.parent.unwrap();
+        }
         // No collisions
         let scope = &mut ctx.heap[self.cur_scope];
         scope.labels.push(new_label_id);
         Ok(())
+    }
     /// Finds a particular labeled statement by its identifier. Once found it
     /// will make sure that the target label does not skip over any variable
     /// declarations within the scope in which the label was found.
     fn find_label(mut scope_id: ScopeId, ctx: &Ctx, identifier: &Identifier) -> Result<LabeledStatementId, ParseError> {
         loop {
             let scope = &ctx.heap[scope_id];
             let relative_scope_pos = scope.relative_pos_in_parent;
             for label_id in scope.labels.iter().copied() {
                 let label = &ctx.heap[label_id];
                 if label.label == *identifier {
                     // Found the target label, now make sure that the jump to
                     // the label doesn't imply a skipped variable declaration
                     for variable_id in scope.variables.iter().copied() {
                         // TODO: Better to do this in control flow analysis, it
                         //  is legal to skip over a variable declaration if it
                         //  is not actually being used.
                         let variable = &ctx.heap[variable_id];
                         if variable.relative_pos_in_parent > relative_scope_pos && variable.relative_pos_in_parent < label.relative_pos_in_parent {
                             return Err(
                                 ParseError::new_error_str_at_span(&ctx.module().source, identifier.span, "this target label skips over a variable declaration")
                                 .with_info_str_at_span(&ctx.module().source, label.label.span, "because it jumps to this label")
                                 .with_info_str_at_span(&ctx.module().source, variable.identifier.span, "which skips over this variable")
                             );
+                        }
+                    }
                     return Ok(label_id);
+                }
+            }
             if scope.parent.is_none() {
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module().source, identifier.span, "could not find this label"
                 ));
+            }
             scope_id = scope.parent.unwrap();
+        }
+    }
     /// This function will check if the provided scope has a parent that belongs
     /// to a while statement.
     fn scope_is_nested_in_while_statement(mut scope_id: ScopeId, ctx: &Ctx, expected_while_id: WhileStatementId) -> bool {
         let while_stmt = &ctx.heap[expected_while_id];
         loop {
             let scope = &ctx.heap[scope_id];
             if scope.this == while_stmt.scope {
                 return true;
+            }
             match scope.parent {
                 Some(new_scope_id) => scope_id = new_scope_id,
                 None => return false, // walked all the way up, not encountering the while statement
+            }
+        }
+    }
     /// This function should be called while dealing with break/continue
     /// statements. It will try to find the targeted while statement, using the
     /// target label if provided. If a valid target is found then the loop's
     /// ID will be returned, otherwise a parsing error is constructed.
     /// The provided input position should be the position of the break/continue
     /// statement.
     fn resolve_break_or_continue_target(ctx: &Ctx, control_flow: &ControlFlowStatement, span: InputSpan, label: &Option<Identifier>) -> Result<WhileStatementId, ParseError> {
         let target = match label {
             Some(label) => {
                 let target_id = Self::find_label(control_flow.in_scope, ctx, label)?;
                 // Make sure break target is a while statement
                 let target = &ctx.heap[target_id];
                 if let Statement::While(target_stmt) = &ctx.heap[target.body] {
                     // Even though we have a target while statement, the control
                     // flow statement might not be present underneath this
                     // particular labeled while statement.
                     if !Self::scope_is_nested_in_while_statement(control_flow.in_scope, ctx, target_stmt.this) {
                         return Err(ParseError::new_error_str_at_span(
                             &ctx.module().source, label.span, "break statement is not nested under the target label's while statement"
                         ).with_info_str_at_span(
                             &ctx.module().source, target.label.span, "the targeted label is found here"
                         ));
+                    }
                     target_stmt.this
                 } else {
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module().source, label.span, "incorrect break target label, it must target a while loop"
                     ).with_info_str_at_span(
                         &ctx.module().source, target.label.span, "The targeted label is found here"
                     ));
+                }
             },
             None => {
                 // Use the enclosing while statement, the break must be
                 // nested within that while statement
                 if control_flow.in_while.is_invalid() {
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module().source, span, "Break statement is not nested under a while loop"
                     ));
+                }
                 control_flow.in_while
+            }
         };
         // We have a valid target for the break statement. But we need to
         // make sure we will not break out of a synchronous block
+        {
             let target_while = &ctx.heap[target];
             if target_while.in_sync != control_flow.in_sync {
                 // Break is nested under while statement, so can only escape a
                 // sync block if the sync is nested inside the while statement.
                 debug_assert!(!control_flow.in_sync.is_invalid());
                 let sync_stmt = &ctx.heap[control_flow.in_sync];
                 return Err(
                     ParseError::new_error_str_at_span(&ctx.module().source, span, "break may not escape the surrounding synchronous block")
                         .with_info_str_at_span(&ctx.module().source, target_while.span, "the break escapes out of this loop")
                         .with_info_str_at_span(&ctx.module().source, sync_stmt.span, "And would therefore escape this synchronous block")
                 );
+            }
+        }
         Ok(target)
+    }
+}
@@ \ No newline at end of file @@

src/runtime2/component/component.rs

➞

Show inline comments

 /*
  * Default toolkit for creating components. Contains handlers for initiating and
  * responding to various events.
  */
 use std::fmt::{Display as FmtDisplay, Result as FmtResult, Formatter};
 use crate::protocol::eval::{Prompt, EvalError, ValueGroup, Value, ValueId, PortId as EvalPortId};
 use crate::protocol::*;
 use crate::runtime2::*;
 use crate::runtime2::communication::*;
 use super::{CompCtx, CompPDL, CompId};
 use super::component_context::*;
 use super::component_random::*;
 use super::component_internet::*;
 use super::control_layer::*;
 use super::consensus::*;
 pub enum CompScheduling {
     Immediate,
     Requeue,
     Sleep,
     Exit,
+}
 /// Potential error emitted by a component
 pub enum CompError {
     /// Error originating from the code executor. Hence has an associated
     /// source location.
     Executor(EvalError),
     /// Error originating from a component, but not necessarily associated with
     /// a location in the source.
     Component(String), // TODO: Maybe a different embedded value in the future?
     /// Pure runtime error. Not necessarily originating from the component
     /// itself. Should be treated as a very severe runtime-compromising error.
     Runtime(RtError),
+}
 impl FmtDisplay for CompError {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
         match self {
             CompError::Executor(v) => v.fmt(f),
             CompError::Component(v) => v.fmt(f),
             CompError::Runtime(v) => v.fmt(f),
+        }
+    }
+}
 /// Generic representation of a component (as viewed by a scheduler).
 pub(crate) trait Component {
     /// Called upon the creation of the component. Note that the scheduler
     /// context is officially running another component (the component that is
     /// creating the new component).
     fn on_creation(&mut self, comp_id: CompId, sched_ctx: &SchedulerCtx);
     /// Called when a component crashes or wishes to exit. So is not called
     /// right before destruction, other components may still hold a handle to
     /// the component and send it messages!
     fn on_shutdown(&mut self, sched_ctx: &SchedulerCtx);
     /// Called if the component is created by another component and the messages
     /// are being transferred between the two.
     fn adopt_message(&mut self, comp_ctx: &mut CompCtx, message: DataMessage);
     /// Called if the component receives a new message. The component is
     /// responsible for deciding where that messages goes.
     fn handle_message(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx, message: Message);
     /// Called if the component's routine should be executed. The return value
     /// can be used to indicate when the routine should be run again.
     fn run(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx) -> CompScheduling;
+}
 /// Representation of the generic operating mode of a component. Although not
 /// every state may be used by every kind of (builtin) component, this allows
 /// writing standard handlers for particular events in a component's lifetime.
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 pub(crate) enum CompMode {
     NonSync, // not in sync mode
     Sync, // in sync mode, can interact with other components
     SyncEnd, // awaiting a solution, i.e. encountered the end of the sync block
     BlockedGet, // blocked because we need to receive a message on a particular port
     BlockedPut, // component is blocked because the port is blocked
     BlockedSelect, // waiting on message to complete the select statement
     PutPortsBlockedTransferredPorts, // sending a message with ports, those sent ports are (partly) blocked
     PutPortsBlockedAwaitingAcks, // sent out PPC message for blocking transferred ports, now awaiting Acks
     PutPortsBlockedSendingPort, // sending a message with ports, message sent through a still-blocked port
     NewComponentBlocked, // waiting until ports are in the appropriate state to create a new component
     StartExit, // temporary state: if encountered then we start the shutdown process.
     BusyExit, // temporary state: waiting for Acks for all the closed ports, potentially waiting for sync round to finish
     Exit, // exiting: shutdown process started, now waiting until the reference count drops to 0
+}
 impl CompMode {
     pub(crate) fn is_in_sync_block(&self) -> bool {
         use CompMode::*;
         match self {
             Sync | SyncEnd | BlockedGet | BlockedPut | BlockedSelect |
                 PutPortsBlockedTransferredPorts |
                 PutPortsBlockedAwaitingAcks |
                 PutPortsBlockedSendingPort => true,
             NonSync | NewComponentBlocked | StartExit | BusyExit | Exit => false,
+        }
+    }
     pub(crate) fn is_busy_exiting(&self) -> bool {
         use CompMode::*;
         match self {
             NonSync | Sync | SyncEnd | BlockedGet | BlockedPut | BlockedSelect |
             PutPortsBlockedTransferredPorts |
             PutPortsBlockedAwaitingAcks |
             PutPortsBlockedSendingPort |
                 NewComponentBlocked => false,
             StartExit | BusyExit => true,
             Exit => false,
+        }
+    }
+}
 #[derive(Debug)]
 pub(crate) enum ExitReason {
     Termination, // regular termination of component
     ErrorInSync,
     ErrorNonSync,
+}
 impl ExitReason {
     pub(crate) fn is_in_sync(&self) -> bool {
         use ExitReason::*;
         match self {
             Termination | ErrorNonSync => false,
             ErrorInSync => true,
+        }
+    }
     pub(crate) fn is_error(&self) -> bool {
         use ExitReason::*;
         match self {
             Termination => false,
             ErrorInSync | ErrorNonSync => true,
+        }
+    }
+}
 /// Component execution state: the execution mode along with some descriptive
 /// fields. Fields are public for ergonomic reasons, use member functions when
 /// appropriate.
 pub(crate) struct CompExecState {
     pub mode: CompMode,
     pub mode_port: PortId, // valid if blocked on a port (put/get)
     pub mode_value: ValueGroup, // valid if blocked on a put
     pub mode_component: (ProcedureDefinitionId, TypeId),
     pub exit_reason: ExitReason, // valid if in StartExit/BusyExit/Exit mode
+}
 impl CompExecState {
     pub(crate) fn new() -> Self {
         return Self{
             mode: CompMode::NonSync,
             mode_port: PortId::new_invalid(),
             mode_value: ValueGroup::default(),
             mode_component: (ProcedureDefinitionId::new_invalid(), TypeId::new_invalid()),
             exit_reason: ExitReason::Termination,
+        }
+    }
     pub(crate) fn set_as_start_exit(&mut self, reason: ExitReason) {
         self.mode = CompMode::StartExit;
         self.exit_reason = reason;
+    }
     pub(crate) fn set_as_blocked_get(&mut self, port: PortId) {
         self.mode = CompMode::BlockedGet;
         self.mode_port = port;
         debug_assert!(self.mode_value.values.is_empty());
+    }
     pub(crate) fn set_as_create_component_blocked(
         &mut self, proc_id: ProcedureDefinitionId, type_id: TypeId,
         arguments: ValueGroup
     ) {
         self.mode = CompMode::NewComponentBlocked;
         self.mode_value = arguments;
         self.mode_component = (proc_id, type_id);
+    }
     pub(crate) fn is_blocked_on_get(&self, port: PortId) -> bool {
         return
             self.mode == CompMode::BlockedGet &&
             self.mode_port == port;
+    }
     pub(crate) fn set_as_blocked_put_without_ports(&mut self, port: PortId, value: ValueGroup) {
         self.mode = CompMode::BlockedPut;
         self.mode_port = port;
         self.mode_value = value;
+    }
     pub(crate) fn set_as_blocked_put_with_ports(&mut self, port: PortId, value: ValueGroup) {
         self.mode = CompMode::PutPortsBlockedTransferredPorts;
         self.mode_port = port;
         self.mode_value = value;
+    }
     pub(crate) fn is_blocked_on_put_without_ports(&self, port: PortId) -> bool {
         return
             self.mode == CompMode::BlockedPut &&
             self.mode_port == port;
+    }
     pub(crate) fn is_blocked_on_create_component(&self) -> bool {
         return self.mode == CompMode::NewComponentBlocked;
+    }
+}
 // TODO: Replace when implementing port sending. Should probably be incorporated
 //  into CompCtx (and rename CompCtx into CompComms)
 pub(crate) type InboxMain = Vec<Option<DataMessage>>;
 pub(crate) type InboxMainRef = [Option<DataMessage>];
 pub(crate) type InboxBackup = Vec<DataMessage>;
 /// Creates a new component based on its definition. Meaning that if it is a
 /// user-defined component then we set up the PDL code state. Otherwise we
 /// construct a custom component. This does NOT take care of port and message
 /// management.
 pub(crate) fn create_component(
     protocol: &ProtocolDescription,
     definition_id: ProcedureDefinitionId, type_id: TypeId,
     arguments: ValueGroup, num_ports: usize
 ) -> Box<dyn Component> {
     let definition = &protocol.heap[definition_id];
     debug_assert_eq!(definition.kind, ProcedureKind::Component);
     if definition.source.is_builtin() {
         // Builtin component
         let component: Box<dyn Component> = match definition.source {
             ProcedureSource::CompRandomU32 => Box::new(ComponentRandomU32::new(arguments)),
             ProcedureSource::CompTcpClient => Box::new(ComponentTcpClient::new(arguments)),
             ProcedureSource::CompTcpListener => Box::new(ComponentTcpListener::new(arguments)),
             _ => unreachable!(),
         };
         return component;
     } else {
         // User-defined component
         let prompt = Prompt::new(
             &protocol.types, &protocol.heap,
             definition_id, type_id, arguments
         );
         let component = CompPDL::new(prompt, num_ports);
         return Box::new(component);
+    }
+}
 // -----------------------------------------------------------------------------
 // Generic component messaging utilities (for sending and receiving)
 // -----------------------------------------------------------------------------
 /// Default handling of sending a data message. In case the port is blocked then
 /// the `ExecState` will become blocked as well. Note that
 /// `default_handle_control_message` will ensure that the port becomes
 /// unblocked if so instructed by the receiving component. The returned
 /// scheduling value must be used.
 #[must_use]
 pub(crate) fn default_send_data_message(
     exec_state: &mut CompExecState, transmitting_port_id: PortId,
     port_instruction: PortInstruction, value: ValueGroup,
     sched_ctx: &SchedulerCtx, consensus: &mut Consensus,
     control: &mut ControlLayer, comp_ctx: &mut CompCtx
 ) -> Result<CompScheduling, (PortInstruction, String)> {
     debug_assert_eq!(exec_state.mode, CompMode::Sync);
     let port_handle = comp_ctx.get_port_handle(transmitting_port_id);
     let port_info = comp_ctx.get_port_mut(port_handle);
     port_info.last_instruction = port_instruction;
     let port_info = comp_ctx.get_port(port_handle);
     debug_assert_eq!(port_info.kind, PortKind::Putter);
     let mut ports = Vec::new();
     find_ports_in_value_group(&value, &mut ports);
     if port_info.state.is_closed() {
         // Note: normally peer is eventually consistent, but if it has shut down
         // then we can be sure it is consistent (I think?)
         return Err((
             port_info.last_instruction,
             format!("Cannot send on this port, as the peer (id:{}) has shut down", port_info.peer_comp_id.0)
         ))
     } else if !ports.is_empty() {
         start_send_message_with_ports(
             transmitting_port_id, port_instruction, value, exec_state,
             comp_ctx, sched_ctx, control
         )?;
         return Ok(CompScheduling::Sleep);
     } else if port_info.state.is_blocked() {
         // Port is blocked, so we cannot send
         exec_state.set_as_blocked_put_without_ports(transmitting_port_id, value);
         return Ok(CompScheduling::Sleep);
     } else {
         // Port is not blocked and no ports to transfer: send to the peer
         let peer_handle = comp_ctx.get_peer_handle(port_info.peer_comp_id);
         let peer_info = comp_ctx.get_peer(peer_handle);
         let annotated_message = consensus.annotate_data_message(comp_ctx, port_info, value);
         peer_info.handle.send_message_logged(sched_ctx, Message::Data(annotated_message), true);
         return Ok(CompScheduling::Immediate);
+    }
+}
 pub(crate) enum IncomingData {
     PlacedInSlot,
     SlotFull(DataMessage),
+}
 /// Default handling of receiving a data message. In case there is no room for
 /// the message it is returned from this function. Note that this function is
 /// different from PDL code performing a `get` on a port; this is the case where
 /// the message first arrives at the component.
 // NOTE: This is supposed to be a somewhat temporary implementation. It would be
 //  nicest if the sending component can figure out it cannot send any more data.
 #[must_use]
 pub(crate) fn default_handle_incoming_data_message(
     exec_state: &mut CompExecState, inbox_main: &mut InboxMain,
     comp_ctx: &mut CompCtx, incoming_message: DataMessage,
     sched_ctx: &SchedulerCtx, control: &mut ControlLayer
 ) -> IncomingData {
     let port_handle = comp_ctx.get_port_handle(incoming_message.data_header.target_port);
     let port_index = comp_ctx.get_port_index(port_handle);
     comp_ctx.get_port_mut(port_handle).received_message_for_sync = true;
     let port_value_slot = &mut inbox_main[port_index];
     let target_port_id = incoming_message.data_header.target_port;
     if port_value_slot.is_none() {
         // We can put the value in the slot
         *port_value_slot = Some(incoming_message);
         // Check if we're blocked on receiving this message.
         dbg_code!({
             // Our port cannot have been blocked itself, because we're able to
             // directly insert the message into its slot.
             assert!(!comp_ctx.get_port(port_handle).state.is_blocked());
         });
         if exec_state.is_blocked_on_get(target_port_id) {
             // Return to normal operation
             exec_state.mode = CompMode::Sync;
             exec_state.mode_port = PortId::new_invalid();
             debug_assert!(exec_state.mode_value.values.is_empty());
+        }
         return IncomingData::PlacedInSlot
     } else {
         // Slot is already full, so if the port was previously opened, it will
         // now become closed
         let port_info = comp_ctx.get_port_mut(port_handle);
         if port_info.state.is_open() {
             port_info.state.set(PortStateFlag::BlockedDueToFullBuffers);
             let (peer_handle, message) =
                 control.initiate_port_blocking(comp_ctx, port_handle);
             let peer = comp_ctx.get_peer(peer_handle);
             peer.handle.send_message_logged(sched_ctx, Message::Control(message), true);
+        }
         return IncomingData::SlotFull(incoming_message)
+    }
+}
 pub(crate) enum GetResult {
     Received(DataMessage),
     NoMessage,
     Error((PortInstruction, String)),
+}
 /// Default attempt at trying to receive from a port (i.e. through a `get`, or
 /// the equivalent operation for a builtin component). `target_port` is the port
 /// we're trying to receive from, and the `target_port_instruction` is the
 /// instruction we're attempting on this port.
 pub(crate) fn default_attempt_get(
     exec_state: &mut CompExecState, target_port: PortId, target_port_instruction: PortInstruction,
     inbox_main: &mut InboxMain, inbox_backup: &mut InboxBackup, sched_ctx: &SchedulerCtx,
     comp_ctx: &mut CompCtx, control: &mut ControlLayer, consensus: &mut Consensus
 ) -> GetResult {
     let port_handle = comp_ctx.get_port_handle(target_port);
     let port_index = comp_ctx.get_port_index(port_handle);
     let port_info = comp_ctx.get_port_mut(port_handle);
     port_info.last_instruction = target_port_instruction;
     if port_info.state.is_closed() {
         let peer_id = port_info.peer_comp_id;
         return GetResult::Error((
             target_port_instruction,
             format!("Cannot get from this port, as the peer component (id:{}) closed the port", peer_id.0)
         ));
+    }
     if let Some(message) = &inbox_main[port_index] {
         if consensus.try_receive_data_message(sched_ctx, comp_ctx, message) {
             // We're allowed to receive this message
             let mut message = inbox_main[port_index].take().unwrap();
             debug_assert_eq!(target_port, message.data_header.target_port);
             // Note: we can still run into an unrecoverable error when actually
             // receiving this message
             match default_handle_received_data_message(
                 target_port, target_port_instruction,
                 &mut message, inbox_main, inbox_backup,
                 comp_ctx, sched_ctx, control, consensus
             ) {
                 Ok(()) => return GetResult::Received(message),
                 Err(location_and_message) => return GetResult::Error(location_and_message)
+            }
         } else {
             // We're not allowed to receive this message. This means that the
             // receiver is attempting to receive something out of order with
             // respect to the sender.
             return GetResult::Error((target_port_instruction, String::from(
                 "Cannot get from this port, as this causes a deadlock. This happens if you `get` in a different order as another component `put`s"
             )));
+        }
     } else {
         // We don't have a message waiting for us and the port is not blocked.
         // So enter the BlockedGet state
         exec_state.set_as_blocked_get(target_port);
         return GetResult::NoMessage;
+    }
+}
 /// Default handling that has been received through a `get`. Will check if any
 /// more messages are waiting, and if the corresponding port was blocked because
 /// of full buffers (hence, will use the control layer to make sure the peer
 /// will become unblocked).
 pub(crate) fn default_handle_received_data_message(
     targeted_port: PortId, _port_instruction: PortInstruction, message: &mut DataMessage,
     inbox_main: &mut InboxMain, inbox_backup: &mut InboxBackup,
     comp_ctx: &mut CompCtx, sched_ctx: &SchedulerCtx, control: &mut ControlLayer,
     consensus: &mut Consensus
 ) -> Result<(), (PortInstruction, String)> {
     let port_handle = comp_ctx.get_port_handle(targeted_port);
     let port_index = comp_ctx.get_port_index(port_handle);
     debug_assert!(inbox_main[port_index].is_none()); // because we've just received from it
     // If we received any ports, add them to the port tracking and inbox struct.
     // Then notify the peers that they can continue sending to this port, but
     // now at a new address.
     for received_port in &mut message.ports {
         // Transfer messages to main/backup inbox
         let _new_inbox_index = inbox_main.len();
         if !received_port.messages.is_empty() {
             inbox_main.push(Some(received_port.messages.remove(0)));
             inbox_backup.extend(received_port.messages.drain(..));
         } else {
             inbox_main.push(None);
+        }
         // Create a new port locally
         let mut new_port_state = received_port.state;
         new_port_state.set(PortStateFlag::Received);
         let new_port_handle = comp_ctx.add_port(
             received_port.peer_comp, received_port.peer_port,
             received_port.kind, new_port_state
         );
         debug_assert_eq!(_new_inbox_index, comp_ctx.get_port_index(new_port_handle));
         comp_ctx.change_port_peer(sched_ctx, new_port_handle, Some(received_port.peer_comp));
         let new_port = comp_ctx.get_port(new_port_handle);
         // Add the port tho the consensus
         consensus.notify_of_new_port(_new_inbox_index, new_port_handle, comp_ctx);
         // Replace all references to the port in the received message
         for message_location in received_port.locations.iter().copied() {
             let value = message.content.get_value_mut(message_location);
             match value {
                 Value::Input(_) => {
                     debug_assert_eq!(new_port.kind, PortKind::Getter);
                     *value = Value::Input(port_id_to_eval(new_port.self_id));
                 },
                 Value::Output(_) => {
                     debug_assert_eq!(new_port.kind, PortKind::Putter);
                     *value = Value::Output(port_id_to_eval(new_port.self_id));
                 },
                 _ => unreachable!(),
+            }
+        }
         // Let the peer know that the port can now be used
         let peer_handle = comp_ctx.get_peer_handle(new_port.peer_comp_id);
         let peer_info = comp_ctx.get_peer(peer_handle);
         peer_info.handle.send_message_logged(sched_ctx, Message::Control(ControlMessage{
             id: ControlId::new_invalid(),
             sender_comp_id: comp_ctx.id,
             target_port_id: Some(new_port.peer_port_id),
             content: ControlMessageContent::PortPeerChangedUnblock(new_port.self_id, comp_ctx.id)
         }), true);
+    }
     // Modify last-known location where port instruction was retrieved
     let port_info = comp_ctx.get_port(port_handle);
     debug_assert_ne!(port_info.last_instruction, PortInstruction::None); // set by caller
     debug_assert!(port_info.state.is_open()); // checked by caller
     // Check if there are any more messages in the backup buffer
     for message_index in 0..inbox_backup.len() {
         let message = &inbox_backup[message_index];
         if message.data_header.target_port == targeted_port {
             // One more message, place it in the slot
             let message = inbox_backup.remove(message_index);
             debug_assert!(comp_ctx.get_port(port_handle).state.is_blocked()); // since we're removing another message from the backup
             inbox_main[port_index] = Some(message);
             return Ok(());
+        }
+    }
     // Did not have any more messages, so if we were blocked, then we need to
     // unblock the port now (and inform the peer of this unblocking)
     if port_info.state.is_set(PortStateFlag::BlockedDueToFullBuffers) {
         let port_info = comp_ctx.get_port_mut(port_handle);
         port_info.state.clear(PortStateFlag::BlockedDueToFullBuffers);
         let (peer_handle, message) = control.cancel_port_blocking(comp_ctx, port_handle);
         let peer_info = comp_ctx.get_peer(peer_handle);
         peer_info.handle.send_message_logged(sched_ctx, Message::Control(message), true);
+    }
     return Ok(());
+}
 /// Handles control messages in the default way. Note that this function may
 /// take a lot of actions in the name of the caller: pending messages may be
 /// sent, ports may become blocked/unblocked, etc. So the execution
 /// (`CompExecState`), control (`ControlLayer`) and consensus (`Consensus`)
 /// state may all change.
 pub(crate) fn default_handle_control_message(
     exec_state: &mut CompExecState, control: &mut ControlLayer, consensus: &mut Consensus,
     message: ControlMessage, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx,
     inbox_main: &mut InboxMain, inbox_backup: &mut InboxBackup
 ) -> Result<(), (PortInstruction, String)> {
     match message.content {
         ControlMessageContent::Ack => {
             default_handle_ack(exec_state, control, message.id, sched_ctx, comp_ctx, consensus, inbox_main, inbox_backup)?;
         },
         ControlMessageContent::BlockPort => {
             // One of our messages was accepted, but the port should be
             // blocked.
             let port_to_block = message.target_port_id.unwrap();
             let port_handle = comp_ctx.get_port_handle(port_to_block);
             let port_info = comp_ctx.get_port_mut(port_handle);
             debug_assert_eq!(port_info.kind, PortKind::Putter);
             port_info.state.set(PortStateFlag::BlockedDueToFullBuffers);
         },
         ControlMessageContent::ClosePort(content) => {
             // Request to close the port. We immediately comply and remove
             // the component handle as well
             let port_to_close = message.target_port_id.unwrap();
             let port_handle = comp_ctx.get_port_handle(port_to_close);
             // We're closing the port, so we will always update the peer of the
             // port (in case of error messages)
             let port_info = comp_ctx.get_port_mut(port_handle);
             port_info.peer_comp_id = message.sender_comp_id;
             port_info.close_at_sync_end = true; // might be redundant (we might set it closed now)
             let peer_comp_id = port_info.peer_comp_id;
             let peer_handle = comp_ctx.get_peer_handle(peer_comp_id);
             // One exception to sending an `Ack` is if we just closed the
             // port ourselves, meaning that the `ClosePort` messages got
             // sent to one another.
             if let Some(control_id) = control.has_close_port_entry(port_handle, comp_ctx) {
                 // The two components (sender and this component) are closing
                 // the channel at the same time. So we don't care about the
                 // content of the `ClosePort` message.
                 default_handle_ack(exec_state, control, control_id, sched_ctx, comp_ctx, consensus, inbox_main, inbox_backup)?;
             } else {
                 // Respond to the message
                 let port_info = comp_ctx.get_port(port_handle);
                 let last_instruction = port_info.last_instruction;
                 let port_has_had_message = port_info.received_message_for_sync;
                 default_send_ack(message.id, peer_handle, sched_ctx, comp_ctx);
                 comp_ctx.change_port_peer(sched_ctx, port_handle, None);
                 // Handle any possible error conditions (which boil down to: the
                 // port has been used, but the peer has died). If not in sync
                 // mode then we close the port immediately.
                 // Note that `port_was_used` does not mean that any messages
                 // were actually received. It might also mean that e.g. the
                 // component attempted a `get`, but there were no messages, so
                 // now it is in the `BlockedGet` state.
                 let port_was_used = last_instruction != PortInstruction::None;
                 if exec_state.mode.is_in_sync_block() {
                     let closed_during_sync_round = content.closed_in_sync_round && port_was_used;
                     let closed_before_sync_round = !content.closed_in_sync_round && !port_has_had_message && port_was_used;
                     if closed_during_sync_round || closed_before_sync_round {
                         return Err((
                             last_instruction,
                             format!("Peer component (id:{}) shut down, so communication cannot (have) succeed(ed)", peer_comp_id.0)
                         ));
+                    }
                 } else {
                     let port_info = comp_ctx.get_port_mut(port_handle);
                     port_info.state.set(PortStateFlag::Closed);
+                }
+            }
         },
         ControlMessageContent::UnblockPort => {
             // We were previously blocked (or already closed)
             let port_to_unblock = message.target_port_id.unwrap();
             let port_handle = comp_ctx.get_port_handle(port_to_unblock);
             let port_info = comp_ctx.get_port_mut(port_handle);
             debug_assert_eq!(port_info.kind, PortKind::Putter);
             debug_assert!(port_info.state.is_set(PortStateFlag::BlockedDueToFullBuffers));
             port_info.state.clear(PortStateFlag::BlockedDueToFullBuffers);
             default_handle_recently_unblocked_port(
                 exec_state, control, consensus, port_handle, sched_ctx,
                 comp_ctx, inbox_main, inbox_backup
             )?;
         },
         ControlMessageContent::PortPeerChangedBlock => {
             // The peer of our port has just changed. So we are asked to
             // temporarily block the port (while our original recipient is
             // potentially rerouting some of the in-flight messages) and
             // Ack. Then we wait for the `unblock` call.
             let port_to_change = message.target_port_id.unwrap();
             let port_handle = comp_ctx.get_port_handle(port_to_change);
             let port_info = comp_ctx.get_port_mut(port_handle);
             let peer_comp_id = port_info.peer_comp_id;
             port_info.state.set(PortStateFlag::BlockedDueToPeerChange);
             let peer_handle = comp_ctx.get_peer_handle(peer_comp_id);
             default_send_ack(message.id, peer_handle, sched_ctx, comp_ctx);
         },
         ControlMessageContent::PortPeerChangedUnblock(new_port_id, new_comp_id) => {
             let port_to_change = message.target_port_id.unwrap();
             let port_handle = comp_ctx.get_port_handle(port_to_change);
             let port_info = comp_ctx.get_port(port_handle);
             debug_assert!(port_info.state.is_set(PortStateFlag::BlockedDueToPeerChange));
             let port_info = comp_ctx.get_port_mut(port_handle);
             port_info.peer_port_id = new_port_id;
             port_info.state.clear(PortStateFlag::BlockedDueToPeerChange);
             comp_ctx.change_port_peer(sched_ctx, port_handle, Some(new_comp_id));
             default_handle_recently_unblocked_port(
                 exec_state, control, consensus, port_handle, sched_ctx,
                 comp_ctx, inbox_main, inbox_backup
             )?;
+        }
+    }
     return Ok(());
+}
 /// Handles a component entering the synchronous block. Will ensure that the
 /// `Consensus` and the `ComponentCtx` are initialized properly.
 pub(crate) fn default_handle_sync_start(
     exec_state: &mut CompExecState, inbox_main: &mut InboxMainRef,
     sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx, consensus: &mut Consensus
 ) {
     sched_ctx.info("Component starting sync mode");
     // If any messages are present for this sync round, set the appropriate flag
     // and notify the consensus handler of the present messages
     consensus.notify_sync_start(comp_ctx);
     for (port_index, message) in inbox_main.iter().enumerate() {
         if let Some(message) = message {
             consensus.handle_incoming_data_message(comp_ctx, message);
             let port_info = comp_ctx.get_port_by_index_mut(port_index);
             port_info.received_message_for_sync = true;
+        }
+    }
     // Modify execution state
     debug_assert_eq!(exec_state.mode, CompMode::NonSync);
     exec_state.mode = CompMode::Sync;
+}
 /// Handles a component that has reached the end of the sync block. This does
 /// not necessarily mean that the component will go into the `NonSync` mode, as
 /// it might have to wait for the leader to finish the round for everyone (see
 /// `default_handle_sync_decision`)
 pub(crate) fn default_handle_sync_end(
     exec_state: &mut CompExecState, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx,
     consensus: &mut Consensus
 ) {
     sched_ctx.info("Component ending sync mode (but possibly waiting for a solution)");
     debug_assert_eq!(exec_state.mode, CompMode::Sync);
     let decision = consensus.notify_sync_end_success(sched_ctx, comp_ctx);
     exec_state.mode = CompMode::SyncEnd;
     default_handle_sync_decision(sched_ctx, exec_state, comp_ctx, decision, consensus);
+}
 /// Handles a component initiating the exiting procedure, and closing all of its
 /// ports. Should only be called once per component (which is ensured by
 /// checking and modifying the mode in the execution state).
 #[must_use]
 pub(crate) fn default_handle_start_exit(
     exec_state: &mut CompExecState, control: &mut ControlLayer,
     sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx, consensus: &mut Consensus
 ) -> CompScheduling {
     debug_assert_eq!(exec_state.mode, CompMode::StartExit);
     for port_index in 0..comp_ctx.num_ports() {
         let port_info = comp_ctx.get_port_by_index_mut(port_index);
         if port_info.state.is_blocked() {
             return CompScheduling::Sleep;
+        }
+    }
     sched_ctx.info(&format!("Component starting exit (reason: {:?})", exec_state.exit_reason));
     exec_state.mode = CompMode::BusyExit;
     let exit_inside_sync = exec_state.exit_reason.is_in_sync();
     // If exiting while inside sync mode, report to the leader of the current
     // round that we've failed.
     if exit_inside_sync {
         let decision = consensus.notify_sync_end_failure(sched_ctx, comp_ctx);
         default_handle_sync_decision(sched_ctx, exec_state, comp_ctx, decision, consensus);
+    }
     // Iterating over ports by index to work around borrowing rules
     for port_index in 0..comp_ctx.num_ports() {
         let port = comp_ctx.get_port_by_index_mut(port_index);
         if port.state.is_closed() || port.state.is_set(PortStateFlag::Transmitted) || port.close_at_sync_end {
             // Already closed, or in the process of being closed
             continue;
+        }
         // Mark as closed
         let port_id = port.self_id;
         port.state.set(PortStateFlag::Closed);
         // Notify peer of closing
         let port_handle = comp_ctx.get_port_handle(port_id);
         let (peer, message) = control.initiate_port_closing(port_handle, exit_inside_sync, comp_ctx);
         let peer_info = comp_ctx.get_peer(peer);
         peer_info.handle.send_message_logged(sched_ctx, Message::Control(message), true);
+    }
     return CompScheduling::Immediate; // to check if we can shut down immediately
+}
 /// Handles a component waiting until all peers are notified that it is quitting
 /// (i.e. after calling `default_handle_start_exit`).
 #[must_use]
 pub(crate) fn default_handle_busy_exit(
     exec_state: &mut CompExecState, control: &ControlLayer,
     sched_ctx: &SchedulerCtx
 ) -> CompScheduling {
     debug_assert_eq!(exec_state.mode, CompMode::BusyExit);
     if control.has_acks_remaining() {
         sched_ctx.info("Component busy exiting, still has `Ack`s remaining");
         return CompScheduling::Sleep;
     } else {
         sched_ctx.info("Component busy exiting, now shutting down");
         exec_state.mode = CompMode::Exit;
         return CompScheduling::Exit;
+    }
+}
 /// Handles a potential synchronous round decision. If there was a decision then
 /// the `Some(success)` value indicates whether the round succeeded or not.
 /// Might also end up changing the `ExecState`.
 ///
 /// Might be called in two cases:
 /// 1. The component is in regular execution mode, at the end of a sync round,
 ///     and is waiting for a solution to the round.
 /// 2. The component has encountered an error during a sync round and is
 ///     exiting, hence is waiting for a "Failure" message from the leader.
 pub(crate) fn default_handle_sync_decision(
     sched_ctx: &SchedulerCtx, exec_state: &mut CompExecState, comp_ctx: &mut CompCtx,
     decision: SyncRoundDecision, consensus: &mut Consensus
 ) -> Option<bool> {
     let success = match decision {
         SyncRoundDecision::None => return None,
         SyncRoundDecision::Solution => true,
         SyncRoundDecision::Failure => false,
     };
     debug_assert!(
         exec_state.mode == CompMode::SyncEnd || (
             exec_state.mode.is_busy_exiting() && exec_state.exit_reason.is_error()
         ) || (
             exec_state.mode.is_in_sync_block() && decision == SyncRoundDecision::Failure
+        )
     );
     sched_ctx.info(&format!("Handling decision {:?} (in mode: {:?})", decision, exec_state.mode));
     consensus.notify_sync_decision(decision);
     if success {
         // We cannot get a success message if the component has encountered an
         // error.
         for port_index in 0..comp_ctx.num_ports() {
             let port_info = comp_ctx.get_port_by_index_mut(port_index);
             if port_info.close_at_sync_end {
                 port_info.state.set(PortStateFlag::Closed);
+            }
             port_info.state.clear(PortStateFlag::Received);
+        }
         debug_assert_eq!(exec_state.mode, CompMode::SyncEnd);
         exec_state.mode = CompMode::NonSync;
         return Some(true);
     } else {
         // We may get failure both in all possible cases. But we should only
         // modify the execution state if we're not already in exit mode
         if !exec_state.mode.is_busy_exiting() {
             sched_ctx.error("failed synchronous round, initiating exit");
             exec_state.set_as_start_exit(ExitReason::ErrorNonSync);
+        }
         return Some(false);
+    }
+}
 /// Special component creation function. This function assumes that the
 /// transferred ports are NOT blocked, and that the channels to whom the ports
 /// belong are fully owned by the creating component. This will be checked in
 /// debug mode.
 pub(crate) fn special_create_component(
     exec_state: &mut CompExecState, sched_ctx: &SchedulerCtx, instantiator_ctx: &mut CompCtx,
     control: &mut ControlLayer, inbox_main: &mut InboxMain, inbox_backup: &mut InboxBackup,
     component_instance: Box<dyn Component>, component_ports: Vec<PortId>,
 ) {
     debug_assert_eq!(exec_state.mode, CompMode::NonSync);
     let reservation = sched_ctx.runtime.start_create_component();
     let mut created_ctx = CompCtx::new(&reservation);
     let mut port_pairs = Vec::new();
     // Retrieve ports
     for instantiator_port_id in component_ports.iter() {
         let instantiator_port_id = *instantiator_port_id;
         let instantiator_port_handle = instantiator_ctx.get_port_handle(instantiator_port_id);
         let instantiator_port = instantiator_ctx.get_port(instantiator_port_handle);
         // Check if conditions for calling this function are valid
         debug_assert!(!instantiator_port.state.is_blocked_due_to_port_change());
         debug_assert_eq!(instantiator_port.peer_comp_id, instantiator_ctx.id);
         // Create port at new component
         let created_port_handle = created_ctx.add_port(
             instantiator_port.peer_comp_id, instantiator_port.peer_port_id,
             instantiator_port.kind, instantiator_port.state
         );
         let created_port = created_ctx.get_port(created_port_handle);
         let created_port_id = created_port.self_id;
         // Store in port pairs
         let is_open = instantiator_port.state.is_open();
         port_pairs.push(PortPair{
             instantiator_id: instantiator_port_id,
             instantiator_handle: instantiator_port_handle,
             created_id: created_port_id,
             created_handle: created_port_handle,
             is_open,
         });
+    }
     // Set peer of the port for the new component
     for pair in port_pairs.iter() {
         let instantiator_port_info = instantiator_ctx.get_port(pair.instantiator_handle);
         let created_port_info = created_ctx.get_port_mut(pair.created_handle);
         // Note: we checked above (in debug mode) that the peer of the port is
         // owned by the creator as well, now check if the peer is transferred
         // as well.
         let created_port_peer_index = port_pairs.iter()
             .position(|v| v.instantiator_id == instantiator_port_info.peer_port_id);
         match created_port_peer_index {
             Some(created_port_peer_index) => {
                 // Both ends of the channel are moving to the new component
                 let peer_pair = &port_pairs[created_port_peer_index];
                 created_port_info.peer_port_id = peer_pair.created_id;
                 created_port_info.peer_comp_id = reservation.id();
             },
             None => {
                 created_port_info.peer_comp_id = instantiator_ctx.id;
                 if pair.is_open {
                     created_ctx.change_port_peer(sched_ctx, pair.created_handle, Some(instantiator_ctx.id));
+                }
+            }
+        }
+    }
     // Store component in runtime storage and retrieve component fields in their
     // name memory location
     let (created_key, created_runtime_component) = sched_ctx.runtime.finish_create_component(
         reservation, component_instance, created_ctx, false
     );
     let created_ctx = &mut created_runtime_component.ctx;
     let created_component = &mut created_runtime_component.component;
     created_component.on_creation(created_key.downgrade(), sched_ctx);
     // Transfer messages and link instantiator to created component
     for pair in port_pairs.iter() {
         instantiator_ctx.change_port_peer(sched_ctx, pair.instantiator_handle, None);
         transfer_messages(inbox_main, inbox_backup, pair, instantiator_ctx, created_ctx, created_component.as_mut());
         instantiator_ctx.remove_port(pair.instantiator_handle);
         let created_port_info = created_ctx.get_port(pair.created_handle);
         if pair.is_open && created_port_info.peer_comp_id == instantiator_ctx.id {
             // Set up channel between instantiator component port, and its peer,
             // which is owned by the new component
             let instantiator_port_handle = instantiator_ctx.get_port_handle(created_port_info.peer_port_id);
             let instantiator_port_info = instantiator_ctx.get_port_mut(instantiator_port_handle);
             instantiator_port_info.peer_port_id = created_port_info.self_id;
             instantiator_ctx.change_port_peer(sched_ctx, instantiator_port_handle, Some(created_ctx.id));
+        }
+    }
     // By definition we did not have any remote peers for the transferred ports,
     // so we can schedule the new component immediately
     sched_ctx.runtime.enqueue_work(created_key);
+}
 /// Puts the component in an execution state where the specified component will
 /// end up being created. The component goes through state changes (driven by
 /// incoming control messages) to make sure that all of the ports that are going
 /// to be transferred are not in a blocked state. Once finished the component
 /// returns to the `NonSync` mode.
 pub(crate) fn default_start_create_component(
     exec_state: &mut CompExecState, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx,
     control: &mut ControlLayer, inbox_main: &mut InboxMain, inbox_backup: &mut InboxBackup,
     definition_id: ProcedureDefinitionId, type_id: TypeId, arguments: ValueGroup
 ) {
     debug_assert_eq!(exec_state.mode, CompMode::NonSync);
     let mut transferred_ports = Vec::new();
     find_ports_in_value_group(&arguments, &mut transferred_ports);
     // Set execution state as waiting until we can create the component. If we
     // can do so right away, then we will.
     exec_state.set_as_create_component_blocked(definition_id, type_id, arguments);
     if ports_not_blocked(comp_ctx, &transferred_ports) {
         perform_create_component(exec_state, sched_ctx, comp_ctx, control, inbox_main, inbox_backup);
+    }
+}
 /// Actually creates a component (and assumes that the caller made sure that
 /// none of the ports are involved in a blocking operation).
 pub(crate) fn perform_create_component(
     exec_state: &mut CompExecState, sched_ctx: &SchedulerCtx, instantiator_ctx: &mut CompCtx,
     control: &mut ControlLayer, inbox_main: &mut InboxMain, inbox_backup: &mut InboxBackup
 ) {
     // Retrieve ports from the arguments
     debug_assert_eq!(exec_state.mode, CompMode::NewComponentBlocked);
     let (procedure_id, procedure_type_id) = exec_state.mode_component;
     let mut arguments = exec_state.mode_value.take();
     let mut ports = Vec::new();
     find_ports_in_value_group(&arguments, &mut ports);
     debug_assert!(ports_not_blocked(instantiator_ctx, &ports));
     // Reserve a location for the new component
     let reservation = sched_ctx.runtime.start_create_component();
     let mut created_ctx = CompCtx::new(&reservation);
     let mut port_pairs = Vec::with_capacity(ports.len());
     // Go over all the ports that will be transferred. Since the ports will get
     // a new ID in the new component, we will take care of that here.
     for (port_location, instantiator_port_id) in &ports {
         // Retrieve port information from instantiator
         let instantiator_port_id = *instantiator_port_id;
         let instantiator_port_handle = instantiator_ctx.get_port_handle(instantiator_port_id);
         let instantiator_port = instantiator_ctx.get_port(instantiator_port_handle);
         // Create port at created component
         let created_port_handle = created_ctx.add_port(
             instantiator_port.peer_comp_id, instantiator_port.peer_port_id,
             instantiator_port.kind, instantiator_port.state
         );
         let created_port = created_ctx.get_port(created_port_handle);
         let created_port_id = created_port.self_id;
         // Modify port ID in the arguments to the new component and store them
         // for later access
         let is_open = instantiator_port.state.is_open();
         port_pairs.push(PortPair{
             instantiator_id: instantiator_port_id,
             instantiator_handle: instantiator_port_handle,
             created_id: created_port_id,
             created_handle: created_port_handle,
             is_open,
         });
         for location in port_location.iter().copied() {
             let value = arguments.get_value_mut(location);
             match value {
                 Value::Input(id) => *id = port_id_to_eval(created_port_id),
                 Value::Output(id) => *id = port_id_to_eval(created_port_id),
                 _ => unreachable!(),
+            }
+        }
+    }
     // For each of the ports in the newly created component we set the peer to

src/runtime2/component/component_internet.rs

➞

Show inline comments

 use crate::protocol::eval::{ValueGroup, Value};
 use crate::runtime2::*;
 use crate::runtime2::component::{CompCtx, CompId, PortInstruction};
 use crate::runtime2::stdlib::internet::*;
 use crate::runtime2::poll::*;
 use super::component::{self, *};
 use super::control_layer::*;
 use super::consensus::*;
 use std::io::ErrorKind as IoErrorKind;
 use std::net::{IpAddr, Ipv4Addr};
 use crate::protocol::{ProcedureDefinitionId, TypeId};
 // -----------------------------------------------------------------------------
 // ComponentTcpClient
 // -----------------------------------------------------------------------------
 enum ClientSocketState {
     Connected(SocketTcpClient),
     Error,
+}
 impl ClientSocketState {
     fn get_socket(&self) -> &SocketTcpClient {
         match self {
             ClientSocketState::Connected(v) => v,
             ClientSocketState::Error => unreachable!(),
+        }
+    }
+}
 /// States from the point of view of the component that is connecting to this
 /// TCP component (i.e. from the point of view of attempting to interface with
 /// a socket).
 #[derive(PartialEq, Debug)]
 enum ClientSyncState {
     AwaitingCmd,
     Getting,
     Putting,
     FinishSync,
     FinishSyncThenQuit,
+}
 pub struct ComponentTcpClient {
     // Properties for the tcp socket
     socket_state: ClientSocketState,
     sync_state: ClientSyncState,
     poll_ticket: Option<PollTicket>,
     inbox_main: InboxMain,
     inbox_backup: InboxBackup,
     pdl_input_port_id: PortId, // input from PDL, so transmitted over socket
     pdl_output_port_id: PortId, // output towards PDL, so received over socket
     // Information about union tags, extracted from PDL
     input_union_send_tag_value: i64,
     input_union_receive_tag_value: i64,
     input_union_finish_tag_value: i64,
     input_union_shutdown_tag_value: i64,
     // Generic component state
     exec_state: CompExecState,
     control: ControlLayer,
     consensus: Consensus,
     // Temporary variables
     byte_buffer: Vec<u8>,
+}
 impl Component for ComponentTcpClient {
     fn on_creation(&mut self, id: CompId, sched_ctx: &SchedulerCtx) {
         // Retrieve type information for messages we're going to receive
         let pd = &sched_ctx.runtime.protocol;
         let cmd_type = pd.find_type(b"std.internet", b"ClientCmd")
             .expect("'ClientCmd' type in the 'std.internet' module");
         let cmd_type = cmd_type
             .as_union();
         self.input_union_send_tag_value = cmd_type.get_variant_tag_value(b"Send").unwrap();
         self.input_union_receive_tag_value = cmd_type.get_variant_tag_value(b"Receive").unwrap();
         self.input_union_finish_tag_value = cmd_type.get_variant_tag_value(b"Finish").unwrap();
         self.input_union_shutdown_tag_value = cmd_type.get_variant_tag_value(b"Shutdown").unwrap();
         // Register socket for async events
         if let ClientSocketState::Connected(socket) = &self.socket_state {
             let self_handle = sched_ctx.runtime.get_component_public(id);
             let poll_ticket = sched_ctx.polling.register(socket, self_handle, true, true)
                 .expect("registering tcp client");
             debug_assert!(self.poll_ticket.is_none());
             self.poll_ticket = Some(poll_ticket);
+        }
+    }
     fn on_shutdown(&mut self, sched_ctx: &SchedulerCtx) {
         if let Some(poll_ticket) = self.poll_ticket.take() {
             sched_ctx.polling.unregister(poll_ticket)
                 .expect("unregistering tcp component");
+        }
+    }
     fn adopt_message(&mut self, _comp_ctx: &mut CompCtx, message: DataMessage) {
         let slot = &mut self.inbox_main[0];
         if slot.is_none() {
             *slot = Some(message);
         } else {
             self.inbox_backup.push(message);
+        }
+    }
     fn handle_message(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx, message: Message) {
         match message {
             Message::Data(message) => {
                 self.handle_incoming_data_message(sched_ctx, comp_ctx, message);
             },
             Message::Sync(message) => {
                 let decision = self.consensus.receive_sync_message(sched_ctx, comp_ctx, message);
                 component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, comp_ctx, decision, &mut self.consensus);
             },
             Message::Control(message) => {
                 if let Err(location_and_message) = component::default_handle_control_message(
                     &mut self.exec_state, &mut self.control, &mut self.consensus,
                     message, sched_ctx, comp_ctx, &mut self.inbox_main, &mut self.inbox_backup
                 ) {
                     component::default_handle_error_for_builtin(&mut self.exec_state, sched_ctx, location_and_message);
+                }
             },
             Message::Poll => {
                 sched_ctx.info("Received polling event");
             },
+        }
+    }
     fn run(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx) -> CompScheduling {
         sched_ctx.info(&format!("Running component ComponentTcpClient (mode: {:?}, sync state: {:?})", self.exec_state.mode, self.sync_state));
         match self.exec_state.mode {
             CompMode::BlockedSelect |
             CompMode::PutPortsBlockedTransferredPorts |
             CompMode::PutPortsBlockedAwaitingAcks |
             CompMode::PutPortsBlockedSendingPort |
             CompMode::NewComponentBlocked => {
                 // Not possible: we never enter this state
                 unreachable!();
             },
             CompMode::NonSync => {
                 // When in non-sync mode
                 match &self.socket_state {
                     ClientSocketState::Connected(_socket) => {
                         if self.sync_state == ClientSyncState::FinishSyncThenQuit {
                             // Previous request was to let the component shut down
                             self.exec_state.set_as_start_exit(ExitReason::Termination);
                         } else {
                             // Reset for a new request
                             self.sync_state = ClientSyncState::AwaitingCmd;
                             component::default_handle_sync_start(
                                 &mut self.exec_state, &mut self.inbox_main, sched_ctx, comp_ctx, &mut self.consensus
                             );
+                        }
                         return CompScheduling::Immediate;
                     },
                     ClientSocketState::Error => {
                         // Could potentially send an error message to the
                         // connected component.
                         self.exec_state.set_as_start_exit(ExitReason::ErrorNonSync);
                         return CompScheduling::Immediate;
+                    }
+                }
             },
             CompMode::Sync => {
                 // When in sync mode: wait for a command to come in
                 match self.sync_state {
                     ClientSyncState::AwaitingCmd => {
                         match component::default_attempt_get(
                             &mut self.exec_state, self.pdl_input_port_id, PortInstruction::NoSource,
                             &mut self.inbox_main, &mut self.inbox_backup, sched_ctx, comp_ctx,
                             &mut self.control, &mut self.consensus
                         ) {
                             GetResult::Received(message) => {
                                 let (tag_value, embedded_heap_pos) = message.content.values[0].as_union();
                                 if tag_value == self.input_union_send_tag_value {
                                     // Retrieve bytes from the message
                                     self.byte_buffer.clear();
                                     let union_content = &message.content.regions[embedded_heap_pos as usize];
                                     debug_assert_eq!(union_content.len(), 1);
                                     let array_heap_pos = union_content[0].as_array();
                                     let array_values = &message.content.regions[array_heap_pos as usize];
                                     self.byte_buffer.reserve(array_values.len());
                                     for value in array_values {
                                         self.byte_buffer.push(value.as_uint8());
+                                    }
                                     self.sync_state = ClientSyncState::Putting;
                                 } else if tag_value == self.input_union_receive_tag_value {
                                     // Component requires a `recv`
                                     self.sync_state = ClientSyncState::Getting;
                                 } else if tag_value == self.input_union_finish_tag_value {
                                     // Component requires us to end the sync round
                                     self.sync_state = ClientSyncState::FinishSync;
                                 } else if tag_value == self.input_union_shutdown_tag_value {
                                     // Component wants to close the connection
                                     self.sync_state = ClientSyncState::FinishSyncThenQuit;
                                 } else {
                                     unreachable!("got tag_value {}", tag_value)
+                                }
                                 return CompScheduling::Immediate;
                             },
                             GetResult::NoMessage => {
                                 return CompScheduling::Sleep;
                             },
                             GetResult::Error(location_and_message) => {
                                 component::default_handle_error_for_builtin(&mut self.exec_state, sched_ctx, location_and_message);
                                 return CompScheduling::Immediate;
+                            }
+                        }
                     },
                     ClientSyncState::Putting => {
                         // We're supposed to send a user-supplied message fully
                         // over the socket. But we might end up blocking. In
                         // that case the component goes to sleep until it is
                         // polled.
                         let socket = self.socket_state.get_socket();
                         while !self.byte_buffer.is_empty() {
                             match socket.send(&self.byte_buffer) {
                                 Ok(bytes_sent) => {
                                     self.byte_buffer.drain(..bytes_sent);
                                 },
                                 Err(err) => {
                                     if err.kind() == IoErrorKind::WouldBlock {
                                         return CompScheduling::Sleep; // wait until notified
                                     } else {
                                         todo!("handle socket.send error {:?}", err)
+                                    }
+                                }
+                            }
+                        }
                         // If here then we're done putting the data, we can
                         // finish the sync round
                         component::default_handle_sync_end(&mut self.exec_state, sched_ctx, comp_ctx, &mut self.consensus);
                         return CompScheduling::Requeue;
                     },
                     ClientSyncState::Getting => {
                         // We're going to try and receive a single message. If
                         // this causes us to end up blocking the component
                         // goes to sleep until it is polled.
                         const BUFFER_SIZE: usize = 1024; // TODO: Move to config
                         let socket = self.socket_state.get_socket();
                         self.byte_buffer.resize(BUFFER_SIZE, 0);
                         match socket.receive(&mut self.byte_buffer) {
                             Ok(num_received) => {
                                 self.byte_buffer.resize(num_received, 0);
                                 let message_content = self.bytes_to_data_message_content(&self.byte_buffer);
                                 let send_result = component::default_send_data_message(
                                     &mut self.exec_state, self.pdl_output_port_id, PortInstruction::NoSource,
                                     message_content, sched_ctx, &mut self.consensus, &mut self.control, comp_ctx
                                 );
                                 if let Err(location_and_message) = send_result {
                                     component::default_handle_error_for_builtin(&mut self.exec_state, sched_ctx, location_and_message);
                                     return CompScheduling::Immediate;
                                 } else {
                                     let scheduling = send_result.unwrap();
                                     self.sync_state = ClientSyncState::AwaitingCmd;
                                     return scheduling;
+                                }
                             },
                             Err(err) => {
                                 if err.kind() == IoErrorKind::WouldBlock {
                                     return CompScheduling::Sleep; // wait until polled
                                 } else {
                                     todo!("handle socket.receive error {:?}", err)
+                                }
+                            }
+                        }
                     },
                     ClientSyncState::FinishSync | ClientSyncState::FinishSyncThenQuit => {
                         component::default_handle_sync_end(&mut self.exec_state, sched_ctx, comp_ctx, &mut self.consensus);
                         return CompScheduling::Requeue;
                     },
+                }
             },
             CompMode::BlockedGet => {
                 // Entered when awaiting a new command
                 debug_assert_eq!(self.sync_state, ClientSyncState::AwaitingCmd);
                 return CompScheduling::Sleep;
             },
             CompMode::SyncEnd | CompMode::BlockedPut =>
                 return CompScheduling::Sleep,
             CompMode::StartExit =>
                 return component::default_handle_start_exit(&mut self.exec_state, &mut self.control, sched_ctx, comp_ctx, &mut self.consensus),
             CompMode::BusyExit =>
                 return component::default_handle_busy_exit(&mut self.exec_state, &mut self.control, sched_ctx),
             CompMode::Exit =>
                 return component::default_handle_exit(&self.exec_state),
+        }
+    }
+}
 impl ComponentTcpClient {
     pub(crate) fn new(arguments: ValueGroup) -> Self {
         debug_assert_eq!(arguments.values.len(), 4);
         // Parsing arguments
         let (ip_address, port) = ip_addr_and_port_from_args(&arguments, 0, 1);
         let input_port = component::port_id_from_eval(arguments.values[2].as_input());
         let output_port = component::port_id_from_eval(arguments.values[3].as_output());
         let socket = SocketTcpClient::new(ip_address, port);
         if let Err(socket) = socket {
             todo!("friendly error reporting: failed to open socket (reason: {:?})", socket);
+        }
         return Self{
             socket_state: ClientSocketState::Connected(socket.unwrap()),
             sync_state: ClientSyncState::AwaitingCmd,
             poll_ticket: None,
             inbox_main: vec![None, None],
             inbox_backup: Vec::new(),
             input_union_send_tag_value: -1,
             input_union_receive_tag_value: -1,
             input_union_finish_tag_value: -1,
             input_union_shutdown_tag_value: -1,
             pdl_input_port_id: input_port,
             pdl_output_port_id: output_port,
             exec_state: CompExecState::new(),
             control: ControlLayer::default(),
             consensus: Consensus::new(),
             byte_buffer: Vec::new(),
+        }
+    }
     pub(crate) fn new_with_existing_connection(socket: SocketTcpClient, input_port: PortId, output_port: PortId) -> Self {
         return Self{
             socket_state: ClientSocketState::Connected(socket),
             sync_state: ClientSyncState::AwaitingCmd,
             poll_ticket: None,
             inbox_main: vec![None, None],
             inbox_backup: Vec::new(),
             input_union_send_tag_value: -1,
             input_union_receive_tag_value: -1,
             input_union_finish_tag_value: -1,
             input_union_shutdown_tag_value: -1,
             pdl_input_port_id: input_port,
             pdl_output_port_id: output_port,
             exec_state: CompExecState::new(),
             control: ControlLayer::default(),
             consensus: Consensus::new(),
             byte_buffer: Vec::new(),
+        }
+    }
     // Handles incoming data from the PDL side (hence, going into the socket)
     fn handle_incoming_data_message(&mut self, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx, message: DataMessage) {
         if self.exec_state.mode.is_in_sync_block() {
             self.consensus.handle_incoming_data_message(comp_ctx, &message);
+        }
         match component::default_handle_incoming_data_message(
             &mut self.exec_state, &mut self.inbox_main, comp_ctx, message, sched_ctx, &mut self.control
         ) {
             IncomingData::PlacedInSlot => {},
             IncomingData::SlotFull(message) => {
                 self.inbox_backup.push(message);
+            }
+        }
+    }
     fn data_message_to_bytes(&self, message: DataMessage, bytes: &mut Vec<u8>) {
         debug_assert_eq!(message.data_header.target_port, self.pdl_input_port_id);
         debug_assert_eq!(message.content.values.len(), 1);
         if let Value::Array(array_pos) = message.content.values[0] {
             let region = &message.content.regions[array_pos as usize];
             bytes.reserve(region.len());
             for value in region {
                 bytes.push(value.as_uint8());
+            }
         } else {
             unreachable!();
+        }
+    }
     fn bytes_to_data_message_content(&self, buffer: &[u8]) -> ValueGroup {
         // Turn bytes into silly executor-style array
         let mut values = Vec::with_capacity(buffer.len());
         for byte in buffer.iter().copied() {
             values.push(Value::UInt8(byte));
+        }
         // Put in a value group
         let mut value_group = ValueGroup::default();
         value_group.regions.push(values);
         value_group.values.push(Value::Array(0));
         return value_group;
+    }
+}
 // -----------------------------------------------------------------------------
 // ComponentTcpListener
 // -----------------------------------------------------------------------------
 enum ListenerSocketState {
     Connected(SocketTcpListener),
     Error,
+}
 impl ListenerSocketState {
     fn get_socket(&self) -> &SocketTcpListener {
         match self {
             ListenerSocketState::Connected(v) => return v,
             ListenerSocketState::Error => unreachable!(),
+        }
+    }
+}
 struct PendingComponent {
     client: SocketTcpClient,
     cmd_rx: PortId,
     data_tx: PortId,
+}
 enum ListenerSyncState {
     AwaitingCmd,
     AcceptCommandReceived,
     AcceptChannelGenerated{ client: SocketTcpClient, cmd_rx: PortId, data_tx: PortId },
     AcceptCommandReceived, // just received `Accept` command
     AcceptChannelGenerated, // created channel, waiting to end the sync round
     AcceptGenerateComponent, // sync ended, back in non-sync, now generate component
     FinishSyncThenQuit,
+}
 impl ListenerSyncState {
     // Bit of a hacky solution: keeps the listener sync state intact, except
     // if it is `AcceptChannelGenerated`, that will be replaced with
     // `AwaitingCmd`. The reason is to move the `client` out.
     fn take(&mut self) -> ListenerSyncState {
         use ListenerSyncState::*;
         match self {
             AwaitingCmd => return AwaitingCmd,
             AcceptCommandReceived => return AcceptCommandReceived,
             FinishSyncThenQuit => return FinishSyncThenQuit,
             AcceptChannelGenerated{ .. } => {
                 let mut swapped = ListenerSyncState::AwaitingCmd;
                 std::mem::swap(self, &mut swapped);
                 return swapped;
+            }
+        }
+    }
+}
 pub struct ComponentTcpListener {
     // Properties for the tcp socket
     socket_state: ListenerSocketState,
     sync_state: ListenerSyncState,
     pending_component: Option<PendingComponent>,
     poll_ticket: Option<PollTicket>,
     inbox_main: InboxMain,
     inbox_backup: InboxBackup,
     pdl_input_port_id: PortId, // input port, receives commands
     pdl_output_port_id: PortId, // output port, sends connections
     // Information about union tags
     // Type information extracted from protocol
     tcp_client_definition: (ProcedureDefinitionId, TypeId),
     input_union_accept_tag: i64,
     input_union_shutdown_tag: i64,
     output_struct_rx_index: usize,
     output_struct_tx_index: usize,
     // Generic component state
     exec_state: CompExecState,
     control: ControlLayer,
     consensus: Consensus,
+}
 impl Component for ComponentTcpListener {
     fn on_creation(&mut self, id: CompId, sched_ctx: &SchedulerCtx) {
         // Retrieve type information for the message with ports we're going to send
         let pd = &sched_ctx.runtime.protocol;
         let cmd_type = pd.find_type(b"std.internet", b"ListenerCmd")
             .expect("'ListenerCmd' type in the 'std.internet' module");
         let cmd_type = cmd_type.as_union();
         self.input_union_accept_tag = cmd_type.get_variant_tag_value(b"Accept").unwrap();
         self.input_union_shutdown_tag = cmd_type.get_variant_tag_value(b"Shutdown").unwrap();
         let conn_type = pd.find_type(b"std.internet", b"TcpConnection")
             .expect("'TcpConnection' type in the 'std.internet' module");
         let conn_type = conn_type.as_struct();
         assert_eq!(conn_type.get_num_struct_fields(), 2);
         self.output_struct_rx_index = conn_type.get_struct_field_index(b"rx").unwrap();
         self.output_struct_tx_index = conn_type.get_struct_field_index(b"tx").unwrap();
         // Register socket for async events
         if let ListenerSocketState::Connected(socket) = &self.socket_state {
             let self_handle = sched_ctx.runtime.get_component_public(id);
             let poll_ticket = sched_ctx.polling.register(socket, self_handle, true, false)
                 .expect("registering tcp listener");
             debug_assert!(self.poll_ticket.is_none());
             self.poll_ticket = Some(poll_ticket);
+        }
+    }
     fn on_shutdown(&mut self, sched_ctx: &SchedulerCtx) {
         if let Some(poll_ticket) = self.poll_ticket.take() {
             sched_ctx.polling.unregister(poll_ticket);
+        }
+    }
     fn adopt_message(&mut self, _comp_ctx: &mut CompCtx, _message: DataMessage) {
         unreachable!();
+    }
     fn handle_message(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx, message: Message) {
         match message {
             Message::Data(_message) => unreachable!(),
             Message::Data(message) => {
                 self.handle_incoming_data_message(sched_ctx, comp_ctx, message);
             },
             Message::Sync(message) => {
                 let decision = self.consensus.receive_sync_message(sched_ctx, comp_ctx, message);
                 component::default_handle_sync_decision(sched_ctx, &mut self.exec_state, comp_ctx, decision, &mut self.consensus);
             },
             Message::Control(message) => {
                 if let Err(location_and_message) = component::default_handle_control_message(
                     &mut self.exec_state, &mut self.control, &mut self.consensus,
                     message, sched_ctx, comp_ctx, &mut self.inbox_main, &mut self.inbox_backup
                 ) {
                     component::default_handle_error_for_builtin(&mut self.exec_state, sched_ctx, location_and_message);
+                }
             },
             Message::Poll => {
                 sched_ctx.info("Received polling event");
             },
+        }
+    }
     fn run(&mut self, sched_ctx: &mut SchedulerCtx, comp_ctx: &mut CompCtx) -> CompScheduling {
-        sched_ctx.info(&format!("Running comonent ComponentTcpListener (mode: {:?})", self.exec_state.mode));
+        sched_ctx.info(&format!("Running component ComponentTcpListener (mode: {:?})", self.exec_state.mode));
         match self.exec_state.mode {
             CompMode::BlockedSelect
                 => unreachable!(),
             CompMode::PutPortsBlockedTransferredPorts |
             CompMode::PutPortsBlockedAwaitingAcks |
             CompMode::PutPortsBlockedSendingPort |
             CompMode::NewComponentBlocked
                 => return CompScheduling::Sleep,
             CompMode::NonSync => {
                 match &self.socket_state {
                     ListenerSocketState::Connected(_socket) => {
-                        match self.sync_state.take() {
                         match self.sync_state {
                             ListenerSyncState::AwaitingCmd => {
                                 component::default_handle_sync_start(
                                     &mut self.exec_state, &mut self.inbox_main, sched_ctx, comp_ctx, &mut self.consensus
                                 );
                             },
                             ListenerSyncState::AcceptCommandReceived => unreachable!(),
                             ListenerSyncState::AcceptChannelGenerated{ client, cmd_rx, data_tx } => {
                             ListenerSyncState::AcceptCommandReceived |
                             ListenerSyncState::AcceptChannelGenerated => unreachable!(),
                             ListenerSyncState::AcceptGenerateComponent => {
                                 // Now that we're outside the sync round, create the tcp client
                                 // component
                                 let socket_component: Box<dyn Component> = Box::new(ComponentTcpClient::new_with_existing_connection(client, cmd_rx, data_tx));
                                 let pending = self.pending_component.take().unwrap();
                                 let socket_component: Box<dyn Component> = Box::new(ComponentTcpClient::new_with_existing_connection(
                                     pending.client, pending.cmd_rx, pending.data_tx
                                 ));
                                 component::special_create_component(
                                     &mut self.exec_state, sched_ctx, comp_ctx, &mut self.control,
                                     &mut self.inbox_main, &mut self.inbox_backup, socket_component,
                                     vec![cmd_rx, data_tx]
+                                    vec![pending.cmd_rx, pending.data_tx]
                                 );
                                 self.sync_state = ListenerSyncState::AwaitingCmd; // superfluous, see ListenerSyncState.take()
                             },
                             ListenerSyncState::FinishSyncThenQuit => {
                                 self.exec_state.set_as_start_exit(ExitReason::Termination);
                             },
+                        }
                         return CompScheduling::Immediate;
                     },
                     ListenerSocketState::Error => {
                         self.exec_state.set_as_start_exit(ExitReason::ErrorNonSync);
                         return CompScheduling::Immediate;
+                    }
+                }
             },
             CompMode::Sync => {
                 match self.sync_state {
                     ListenerSyncState::AwaitingCmd => {
                         match component::default_attempt_get(
                             &mut self.exec_state, self.pdl_input_port_id, PortInstruction::NoSource,
                             &mut self.inbox_main, &mut self.inbox_backup, sched_ctx, comp_ctx,
                             &mut self.control, &mut self.consensus
                         ) {
                             GetResult::Received(message) => {
                                 let (tag_value, _) = message.content.values[0].as_union();
                                 if tag_value == self.input_union_accept_tag {
                                     self.sync_state = ListenerSyncState::AcceptCommandReceived;
                                 } else if tag_value == self.input_union_shutdown_tag {
                                     self.sync_state = ListenerSyncState::FinishSyncThenQuit;
                                 } else {
                                     unreachable!("got tag_value {}", tag_value);
+                                }
                                 return CompScheduling::Immediate;
                             },
                             GetResult::NoMessage => {
                                 return CompScheduling::Sleep;
                             },
                             GetResult::Error(location_and_message) => {
                                 component::default_handle_error_for_builtin(&mut self.exec_state, sched_ctx, location_and_message);
                                 return CompScheduling::Immediate;
+                            }
+                        }
                     },
                     ListenerSyncState::AcceptCommandReceived => {
                         let socket = self.socket_state.get_socket();
                         match socket.accept() {
                             Ok(client) => {
                                 // Create the channels (and the inbox entries, to stay consistent
                                 // with the expectations from the `component` module's functions)
                                 let client = client.unwrap();
                                 let cmd_channel = comp_ctx.create_channel();
                                 let data_channel = comp_ctx.create_channel();
                                 let port_ids = [
                                     cmd_channel.putter_id, cmd_channel.getter_id,
                                     data_channel.putter_id, data_channel.getter_id,
                                 ];
                                 for port_id in port_ids {
                                     let expected_port_index = self.inbox_main.len();
                                     let port_handle = comp_ctx.get_port_handle(port_id);
                                     self.inbox_main.push(None);
                                     self.consensus.notify_of_new_port(expected_port_index, port_handle, comp_ctx);
+                                }
                                 // Construct the message containing the appropriate ports that will
                                 // be sent to the component commanding this listener.
                                 let mut values = ValueGroup::new_stack(vec![
                                     Value::Unassigned, Value::Unassigned
                                 ]);
                                 values.values[self.output_struct_tx_index] = Value::Output(port_id_to_eval(cmd_channel.putter_id));
                                 values.values[self.output_struct_rx_index] = Value::Input(port_id_to_eval(data_channel.getter_id));
                                 let mut values = ValueGroup::new_stack(Vec::with_capacity(1));
                                 values.values.push(Value::Struct(0));
                                 values.regions.push(vec![Value::Unassigned, Value::Unassigned]);
                                 values.regions[0][self.output_struct_tx_index] = Value::Output(port_id_to_eval(cmd_channel.putter_id));
                                 values.regions[0][self.output_struct_rx_index] = Value::Input(port_id_to_eval(data_channel.getter_id));
                                 if let Err(location_and_message) = component::default_send_data_message(
                                     &mut self.exec_state, self.pdl_output_port_id, PortInstruction::NoSource, values,
                                     sched_ctx, &mut self.consensus, &mut self.control, comp_ctx
                                 ) {
                                     component::default_handle_error_for_builtin(
                                         &mut self.exec_state, sched_ctx, location_and_message
                                     );
+                                }
                                 // And finish the consensus round
                                 component::default_handle_sync_end(&mut self.exec_state, sched_ctx, comp_ctx, &mut self.consensus);
                                 // Enter a state such that when we leave the consensus round and
                                 // go back to the nonsync state, that we will actually create the
                                 // tcp client component.
                                 self.sync_state = ListenerSyncState::AcceptChannelGenerated {
                                 // Prepare for finishing the consensus round, and once finished,
                                 // create the tcp client component
                                 self.sync_state = ListenerSyncState::AcceptChannelGenerated;
                                 debug_assert!(self.pending_component.is_none());
                                 self.pending_component = Some(PendingComponent{
                                     client,
                                     cmd_rx: cmd_channel.getter_id,
                                     data_tx: data_channel.putter_id
                                 };
+                                });
                                 return CompScheduling::Requeue;
                             },
                             Err(err) => {
                                 if err.kind() == IoErrorKind::WouldBlock {
                                     return CompScheduling::Sleep;
                                 } else {
                                     todo!("handle listener.accept error {:?}", err)
+                                }
+                            }
+                        }
                     },
                     ListenerSyncState::AcceptChannelGenerated{ .. } => unreachable!(),
                     ListenerSyncState::FinishSyncThenQuit => {
                     ListenerSyncState::AcceptChannelGenerated => {
                         component::default_handle_sync_end(&mut self.exec_state, sched_ctx, comp_ctx, &mut self.consensus);
                         self.sync_state = ListenerSyncState::AcceptGenerateComponent;
                         return CompScheduling::Requeue;
+                    }
                     ListenerSyncState::FinishSyncThenQuit => {
                         component::default_handle_sync_end(&mut self.exec_state, sched_ctx, comp_ctx, &mut self.consensus);
                         return CompScheduling::Requeue;
                     },
                     ListenerSyncState::AcceptGenerateComponent => unreachable!(),
+                }
             },
             CompMode::BlockedGet => {
                 return CompScheduling::Sleep;
             },
             CompMode::SyncEnd | CompMode::BlockedPut
                 => return CompScheduling::Sleep,
             CompMode::StartExit =>
                 return component::default_handle_start_exit(&mut self.exec_state, &mut self.control, sched_ctx, comp_ctx, &mut self.consensus),
             CompMode::BusyExit =>
                 return component::default_handle_busy_exit(&mut self.exec_state, &mut self.control, sched_ctx),
             CompMode::Exit =>
                 return component::default_handle_exit(&self.exec_state),
+        }
+    }
+}
 impl ComponentTcpListener {
     pub(crate) fn new(arguments: ValueGroup) -> Self {
         debug_assert_eq!(arguments.values.len(), 4);
         // Parsing arguments
         let (ip_address, port) = ip_addr_and_port_from_args(&arguments, 0, 1);
         let input_port = component::port_id_from_eval(arguments.values[2].as_input());
         let output_port = component::port_id_from_eval(arguments.values[3].as_output());
         let socket = SocketTcpListener::new(ip_address, port);
         if let Err(socket) = socket {
             todo!("friendly error reporting: failed to open socket (reason: {:?})", socket);
+        }
         return Self {
             socket_state: ListenerSocketState::Connected(socket.unwrap()),
             sync_state: ListenerSyncState::AwaitingCmd,
             pending_component: None,
             poll_ticket: None,
             inbox_main: vec![None, None],
             inbox_backup: InboxBackup::new(),
             pdl_input_port_id: input_port,
             pdl_output_port_id: output_port,
             input_union_accept_tag: -1,
             input_union_shutdown_tag: -1,
             output_struct_tx_index: 0,
             output_struct_rx_index: 0,
             exec_state: CompExecState::new(),
             control: ControlLayer::default(),
             consensus: Consensus::new(),
+        }
+    }
     fn handle_incoming_data_message(&mut self, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx, message: DataMessage) {
         if self.exec_state.mode.is_in_sync_block() {
             self.consensus.handle_incoming_data_message(comp_ctx, &message);
+        }
         match component::default_handle_incoming_data_message(
             &mut self.exec_state, &mut self.inbox_main, comp_ctx, message, sched_ctx, &mut self.control
         ) {
             IncomingData::PlacedInSlot => {},
             IncomingData::SlotFull(message) => {
                 self.inbox_backup.push(message);
+            }
+        }
+    }
+}
 fn ip_addr_and_port_from_args(
     arguments: &ValueGroup, ip_index: usize, port_index: usize
 ) -> (IpAddr, u16) {
     debug_assert!(ip_index < arguments.values.len());
     debug_assert!(port_index < arguments.values.len());
     // Parsing IP address
     let ip_heap_pos = arguments.values[0].as_array();
     let ip_elements = &arguments.regions[ip_heap_pos as usize];
     let ip_address = match ip_elements.len() {
 => IpAddr::V4(Ipv4Addr::UNSPECIFIED),
 => IpAddr::V4(Ipv4Addr::new(
             ip_elements[0].as_uint8(), ip_elements[1].as_uint8(),
             ip_elements[2].as_uint8(), ip_elements[3].as_uint8()
         )),
         _ => todo!("friendly error reporting: ip should contain 4 octets (or 0 for unspecified)")
     };
     let port = arguments.values[port_index].as_uint16();
     return (ip_address, port);
+}

src/runtime2/tests/internet.rs

➞

Show inline comments

 use super::*;
 // silly test to make sure that the PDL will never be an issue when doing TCP
 // stuff with the actual components
 #[test]
 fn test_stdlib_file() {
     compile_and_create_component("
     import std.internet as inet;
     comp fake_listener_once(out<inet::TcpConnection> tx) {
         channel cmd_tx -> cmd_rx;
         channel data_tx -> data_rx;
         new fake_socket(cmd_rx, data_tx);
         sync put(tx, inet::TcpConnection{
             tx: cmd_tx,
             rx: data_rx,
         });
+    }
     comp fake_socket(in<inet::ClientCmd> cmds, out<u8[]> tx) {
         auto to_send = {};
         auto shutdown = false;
         while (!shutdown) {
             auto keep_going = true;
             sync {
                 while (keep_going) {
                     auto cmd = get(cmds);
                     if (let inet::ClientCmd::Send(data) = cmd) {
                         to_send = data;
                         keep_going = false;
                     } else if (let inet::ClientCmd::Receive = cmd) {
                         put(tx, to_send);
                     } else if (let inet::ClientCmd::Finish = cmd) {
                         keep_going = false;
                     } else if (let inet::ClientCmd::Shutdown = cmd) {
                         keep_going = false;
                         shutdown = true;
+                    }
+                }
+            }
+        }
+    }
     comp fake_client(inet::TcpConnection conn) {
         sync put(conn.tx, inet::ClientCmd::Send({1, 3, 3, 7}));
         sync {
             put(conn.tx, inet::ClientCmd::Receive);
             auto val = get(conn.rx);
             while (val[0] != 1 || val[1] != 3 || val[2] != 3 || val[3] != 7) {
                 print(\"this is going very wrong\");
+            }
             put(conn.tx, inet::ClientCmd::Finish);
+        }
         sync put(conn.tx, inet::ClientCmd::Shutdown);
+    }
     comp constructor() {
         channel conn_tx -> conn_rx;
         new fake_listener_once(conn_tx);
         // Same crap as before:
         channel cmd_tx -> unused_cmd_rx;
         channel unused_data_tx -> data_rx;
         auto connection = inet::TcpConnection{ tx: cmd_tx, rx: data_rx };
         sync {
             connection = get(conn_rx);
+        }
         new fake_client(connection);
+    }
     ", "constructor", no_args());
+}
 #[test]
 fn test_tcp_listener_and_client() {
     compile_and_create_component("
     import std.internet::*;
     func listen_port() -> u16 {
         return 2393;
+    }
     comp server(u32 num_connections) {
         // Start tcp listener
         channel listen_cmd_tx -> listen_cmd_rx;
         channel listen_conn_tx -> listen_conn_rx;
         new tcp_listener({}, listen_port(), listen_cmd_rx, listen_conn_tx);
         // Fake channels such that we can create a dummy connection variable
         channel client_cmd_tx -> unused_client_cmd_rx;
         channel unused_client_data_tx -> client_data_rx;
         auto new_connection = TcpConnection{
             tx: client_cmd_tx,
             rx: client_data_rx,
         };
         auto connection_counter = 0;
         while (connection_counter < num_connections) {
             // Wait until we get a connection
             print(\"server: waiting for an accepted connection\");
             sync {
                 put(listen_cmd_tx, ListenerCmd::Accept);
                 new_connection = get(listen_conn_rx);
+            }
             // We have a new connection, spawn an 'echoer' for it
             print(\"server: spawning an echo'ing component\");
             new echo_machine(new_connection);
             connection_counter += 1;
+        }
         // Shut down the listener
         print(\"server: shutting down listener\");
+    }
     // Waits for a single TCP byte (to simplify potentially having to
     // concatenate requests) and echos it
     comp echo_machine(TcpConnection conn) {
         auto data_to_echo = {};
         // Wait for a message
         sync {
             print(\"echo: receiving data\");
             put(conn.tx, ClientCmd::Receive);
             data_to_echo = get(conn.rx);
             put(conn.tx, ClientCmd::Finish);
+        }
         // Echo the message
         print(\"echo: sending back data\");
         sync put(conn.tx, ClientCmd::Send(data_to_echo));
         // Ask the tcp connection to shut down
         print(\"echo: shutting down\");
         sync put(conn.tx, ClientCmd::Shutdown);
+    }
     comp echo_requester(u8 byte_to_send) {
         channel cmd_tx -> cmd_rx;
         channel data_tx -> data_rx;
         new tcp_client({127, 0, 0, 1}, listen_port(), cmd_rx, data_tx);
         // Send the message
         print(\"requester: sending bytes\");
         sync put(cmd_tx, ClientCmd::Send({ byte_to_send }));
         // Receive the echo'd byte
         auto received_byte = byte_to_send + 1;
         sync {
             print(\"requester: receiving echo response\");
             put(cmd_tx, ClientCmd::Receive);
             received_byte = get(data_rx)[0];
             put(cmd_tx, ClientCmd::Finish);
+        }
         // Silly check, as always
         while (byte_to_send != received_byte) {
             print(\"requester: Oh no! The echo is an otherworldly distorter\");
+        }
         // Shut down the TCP connection
         print(\"requester: shutting down TCP component\");
         sync put(cmd_tx, ClientCmd::Shutdown);
+    }
     comp constructor() {
         auto num_connections = 1;
         new server(num_connections);
         auto connection_index = 0;
         while (connection_index < num_connections) {
             new echo_requester(cast(connection_index));
+        }
+    }
     ", "constructor", no_args());
+}
@@ \ No newline at end of file @@

std/std.internet.pdl

➞

Show inline comments

 #module std.internet
 union ClientCmd {
     Send(u8[]),
     Receive,
     Finish,
     Shutdown,
+}
 comp tcp_client(u8[] ip, u16 port, in<ClientCmd> cmds, out<u8[]> rx) {
     #builtin
+}
 union ListenerCmd {
     Accept,
     Shutdown,
+}
 struct TcpConnection {
     out<ClientCmd> tx,
     in<u8[]> rx,
+}
-/* comp tcp_listener(u8[] ip, u16 port, in<ListenerCmd> cmds, out<TcpConnection> rx) {
 comp tcp_listener(u8[] ip, u16 port, in<ListenerCmd> cmds, out<TcpConnection> rx) {
     #builtin
 } */
@@ \ No newline at end of file @@
+}
@@ \ No newline at end of file @@

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