CSY/reowolf Changeset - ce77f83608df · Centrum Wiskunde & Informatica (CWI)

Changeset - ce77f83608df

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MH - 4 years ago 2021-05-26 20:32:57
contact@maxhenger.nl

Integrate with old runtime, pending some tiny fixes

4 files changed:

src/protocol/eval/executor.rs

113

src/protocol/eval/value.rs

src/protocol/mod.rs

src/protocol/parser/pass_definitions.rs

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src/protocol/eval/executor.rs

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 use std::collections::VecDeque;
 use super::value::*;
 use super::store::*;
 use super::error::*;
 use crate::protocol::*;
 use crate::protocol::ast::*;
 use crate::protocol::type_table::*;
 macro_rules! debug_enabled { () => { false }; }
 macro_rules! debug_log {
     ($format:literal) => {
         enabled_debug_print!(false, "exec", $format);
     };
     ($format:literal, $($args:expr),*) => {
         enabled_debug_print!(false, "exec", $format, $($args),*);
     };
+}
 #[derive(Debug, Clone)]
 pub(crate) enum ExprInstruction {
     EvalExpr(ExpressionId),
     PushValToFront,
+}
 #[derive(Debug, Clone)]
 pub(crate) struct Frame {
     pub(crate) definition: DefinitionId,
     pub(crate) monomorph_idx: i32,
     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: DefinitionId, monomorph_idx: i32) -> Self {
         let definition = &heap[definition_id];
         let first_statement = match definition {
             Definition::Component(definition) => definition.body,
             Definition::Function(definition) => definition.body,
             _ => unreachable!("initializing frame with {:?} instead of a function/component", definition),
         };
         // Another not-so-pretty thing that has to be replaced somewhere in the
         // future...
         fn determine_max_stack_size(heap: &Heap, block_id: BlockStatementId, max_size: &mut u32) {
             let block_stmt = &heap[block_id];
             debug_assert!(block_stmt.next_unique_id_in_scope >= 0);
             // Check current block
             let cur_size = block_stmt.next_unique_id_in_scope as u32;
             if cur_size > *max_size { *max_size = cur_size; }
             // And child blocks
             for child_scope in &block_stmt.scope_node.nested {
                 determine_max_stack_size(heap, child_scope.to_block(), max_size);
+            }
+        }
         let mut max_stack_size = 0;
         determine_max_stack_size(heap, first_statement, &mut max_stack_size);
         Frame{
             definition: definition_id,
             monomorph_idx,
             position: first_statement.upcast(),
             expr_stack: VecDeque::with_capacity(128),
             expr_values: VecDeque::with_capacity(128),
             max_stack_size,
+        }
+    }
     /// Prepares a single expression for execution. This involves walking the
     /// expression tree and putting them in the `expr_stack` such that
     /// continuously popping from its back will evaluate the expression. The
     /// results of each expression will be stored by pushing onto `expr_values`.
     pub fn prepare_single_expression(&mut self, heap: &Heap, expr_id: ExpressionId) {
         debug_assert!(self.expr_stack.is_empty());
         self.expr_values.clear(); // May not be empty if last expression result(s) were discarded
         self.serialize_expression(heap, expr_id);
+    }
     /// Prepares multiple expressions for execution (i.e. evaluating all
     /// function arguments or all elements of an array/union literal). Per
     /// expression this works the same as `prepare_single_expression`. However
     /// after each expression is evaluated we insert a `PushValToFront`
     /// instruction
     pub fn prepare_multiple_expressions(&mut self, heap: &Heap, expr_ids: &[ExpressionId]) {
         debug_assert!(self.expr_stack.is_empty());
         self.expr_values.clear();
         for expr_id in expr_ids {
             self.expr_stack.push_back(ExprInstruction::PushValToFront);
             self.serialize_expression(heap, *expr_id);
+        }
+    }
     /// Performs depth-first serialization of expression tree. Let's not care
     /// about performance for a temporary runtime implementation
     fn serialize_expression(&mut self, heap: &Heap, id: ExpressionId) {
         self.expr_stack.push_back(ExprInstruction::EvalExpr(id));
         match &heap[id] {
             Expression::Assignment(expr) => {
                 self.serialize_expression(heap, expr.left);
                 self.serialize_expression(heap, expr.right);
             },
             Expression::Binding(expr) => {
                 self.serialize_expression(heap, expr.bound_to);
                 self.serialize_expression(heap, expr.bound_from);
             },
             Expression::Conditional(expr) => {
                 self.serialize_expression(heap, expr.test);
             },
             Expression::Binary(expr) => {
                 self.serialize_expression(heap, expr.left);
                 self.serialize_expression(heap, expr.right);
             },
             Expression::Unary(expr) => {
                 self.serialize_expression(heap, expr.expression);
             },
             Expression::Indexing(expr) => {
                 self.serialize_expression(heap, expr.index);
                 self.serialize_expression(heap, expr.subject);
             },
             Expression::Slicing(expr) => {
                 self.serialize_expression(heap, expr.from_index);
                 self.serialize_expression(heap, expr.to_index);
                 self.serialize_expression(heap, expr.subject);
             },
             Expression::Select(expr) => {
                 self.serialize_expression(heap, expr.subject);
             },
             Expression::Literal(expr) => {
                 // Here we only care about literals that have subexpressions
                 match &expr.value {
                     Literal::Null | Literal::True | Literal::False |
                     Literal::Character(_) | Literal::String(_) |
                     Literal::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);
+                        }
+                    }
+                }
             },
             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
+            }
+        }
+    }
+}
 type EvalResult = Result<EvalContinuation, EvalError>;
 pub enum EvalContinuation {
     Stepping,
     Inconsistent,
     Terminal,
     SyncBlockStart,
     SyncBlockEnd,
     NewComponent(DefinitionId, i32, ValueGroup),
     BlockFires(Value),
     BlockGet(Value),
     Put(Value, Value),
+}
 // 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: DefinitionId, monomorph_idx: i32, args: ValueGroup) -> Self {
         let mut prompt = Self{
             frames: Vec::new(),
             store: Store::new(),
         };
         // Maybe do typechecking in the future?
         debug_assert!((monomorph_idx as usize) < _types.get_base_definition(&def).unwrap().definition.procedure_monomorphs().len());
         let new_frame = Frame::new(heap, def, monomorph_idx);
         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
+    }
     pub(crate) fn step(&mut self, types: &TypeTable, heap: &Heap, modules: &[Module], ctx: &mut EvalContext) -> 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].is_function() {
                 todo!("End of function without return, return an evaluation error");
+            }
             return Ok(EvalContinuation::Terminal);
+        }
         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, subject_heap_pos) = 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 = subject.as_array();
                                     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)), subject_heap_pos)
                                 },
                                 _ => {
                                     // 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 = subject.as_array();
                                     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), subject_heap_pos)
                                 },
                             };
                             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)
                             let array_heap_pos = deref_subject.as_array();
                             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(Value::Array(new_heap_pos));
                             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 = types.get_procedure_expression_data(&cur_frame.definition, cur_frame.monomorph_idx);
                             let field_idx = mono_data.expr_data[expr.unique_id_in_definition as usize].field_or_monomorph_idx 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 = subject.as_struct();
                                     (None, Value::Ref(ValueId::Heap(subject_heap_pos, field_idx)))
                                 },
                                 _ => {
                                     let subject_heap_pos = subject.as_struct();
                                     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::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 def_types = types.get_procedure_expression_data(&cur_frame.definition, cur_frame.monomorph_idx);
                                     let concrete_type = &def_types.expr_data[expr.unique_id_in_definition as usize].expr_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)
+                                }
                             };
                             cur_frame.expr_values.push_back(value);
                         },
                         Expression::Cast(expr) => {
                             let mono_data = types.get_procedure_expression_data(&cur_frame.definition, cur_frame.monomorph_idx);
                             let output_type = &mono_data.expr_data[expr.unique_id_in_definition as usize].expr_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, output_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();
                                     match ctx.get(value.clone(), &mut self.store) {
                                         Some(result) => {
                                             cur_frame.expr_values.push_back(result)
                                         },
                                         None => {
                                             cur_frame.expr_values.push_front(value.clone());
                                             cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr_id));
                                             return Ok(EvalContinuation::BlockGet(value));
+                                        }
+                                    }
                                 },
                                 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 msg_value = cur_frame.expr_values.pop_front().unwrap();
                                     let deref_msg_value = self.store.maybe_read_ref(&msg_value).clone();
                                     if ctx.did_put(deref_port_value.clone()) {
                                         // We're fine, deallocate in case the expression value stack
                                         // held an owned value
                                         self.store.drop_value(msg_value.get_heap_pos());
                                     } else {
                                         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));
                                         return Ok(EvalContinuation::Put(deref_port_value, deref_msg_value));
+                                    }
                                 },
                                 Method::Fires => {
                                     let port_value = cur_frame.expr_values.pop_front().unwrap();
                                     let port_value_deref = self.store.maybe_read_ref(&port_value).clone();
                                     match ctx.fires(port_value_deref.clone()) {
                                         None => {
                                             cur_frame.expr_values.push_front(port_value);
                                             cur_frame.expr_stack.push_back(ExprInstruction::EvalExpr(expr_id));
                                             return Ok(EvalContinuation::BlockFires(port_value_deref));
                                         },
                                         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::UserComponent => todo!("component creation"),
                                 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::Inconsistent)
+                                    }
                                 },
                                 Method::UserComponent => {
                                     // This is actually handled by the evaluation
                                     // of the statement.
                                     debug_assert_eq!(heap[expr.definition].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 = types.get_procedure_expression_data(&cur_frame.definition, cur_frame.monomorph_idx);
                                     let call_data = &mono_data.expr_data[expr.unique_id_in_definition as usize];
                                     // Push the new frame and reserve its stack size
                                     let new_frame = Frame::new(heap, expr.definition, call_data.field_or_monomorph_idx);
                                     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);
                                 },
                                 _ => todo!("other builtins"),
+                            }
                         },
                         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) => {
                 cur_frame.position = stmt.statements[0];
                 Ok(EvalContinuation::Stepping)
             },
             Statement::EndBlock(stmt) => {
                 let block = &heap[stmt.start_block];
                 self.store.clear_stack(block.first_unique_id_in_scope as usize);
                 cur_frame.position = stmt.next;
                 Ok(EvalContinuation::Stepping)
             },
             Statement::Local(stmt) => {
                 match stmt {
                     LocalStatement::Memory(stmt) => {
                         let variable = &heap[stmt.variable];
                         self.store.write(ValueId::Stack(variable.unique_id_in_scope as u32), Value::Unassigned);
                         cur_frame.position = stmt.next;
                     },
                     LocalStatement::Channel(stmt) => {
                         let [from_value, to_value] = ctx.new_channel();
                         self.store.write(ValueId::Stack(heap[stmt.from].unique_id_in_scope as u32), from_value);
                         self.store.write(ValueId::Stack(heap[stmt.to].unique_id_in_scope as u32), to_value);
                         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().as_bool();
                 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_body.upcast();
                 } else if let Some(false_body) = stmt.false_body {
                     cur_frame.position = false_body.upcast();
                 } 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;
                 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().as_bool();
                 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.upcast();
                 } else {
                     cur_frame.position = stmt.end_while.upcast();
+                }
                 Ok(EvalContinuation::Stepping)
             },
             Statement::EndWhile(stmt) => {
                 cur_frame.position = stmt.next;
                 Ok(EvalContinuation::Stepping)
             },
             Statement::Break(stmt) => {
                 cur_frame.position = stmt.target.unwrap().upcast();
                 Ok(EvalContinuation::Stepping)
             },
             Statement::Continue(stmt) => {
                 cur_frame.position = stmt.target.unwrap().upcast();
                 Ok(EvalContinuation::Stepping)
             },
             Statement::Synchronous(stmt) => {
                 cur_frame.position = stmt.body.upcast();
                 Ok(EvalContinuation::SyncBlockStart)
             },
             Statement::EndSynchronous(stmt) => {
                 cur_frame.position = stmt.next;
                 Ok(EvalContinuation::SyncBlockEnd)
             },
             Statement::Return(stmt) => {
                 debug_assert!(heap[cur_frame.definition].is_function());
                 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::Terminal);
+                }
                 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.unwrap().upcast();
                 Ok(EvalContinuation::Stepping)
             },
             Statement::New(stmt) => {
                 let call_expr = &heap[stmt.expression];
                 debug_assert!(heap[call_expr.definition].is_component());
                 debug_assert_eq!(
                     cur_frame.expr_values.len(), heap[call_expr.definition].parameters().len(),
                     "mismatch in expr stack size and number of arguments for new statement"
                 );
                 let mono_data = types.get_procedure_expression_data(&cur_frame.definition, cur_frame.monomorph_idx);
                 let expr_data = &mono_data.expr_data[call_expr.unique_id_in_definition as usize];
                 // 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;
                 todo!("Make sure this is handled correctly, transfer 'heap' values to another Prompt");
                 Ok(EvalContinuation::NewComponent(call_expr.definition, expr_data.field_or_monomorph_idx, 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();
+                // 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::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
+    }
+}
@@ \ No newline at end of file @@

src/protocol/eval/value.rs

➞

Show inline comments

 use super::store::*;
 use crate::PortId;
 use crate::protocol::ast::{
     AssignmentOperator,
     BinaryOperator,
     UnaryOperator,
     ConcreteType,
     ConcreteTypePart,
 };
 use crate::protocol::parser::token_parsing::*;
 pub type StackPos = u32;
 pub type HeapPos = u32;
 #[derive(Debug, Copy, Clone)]
 pub enum ValueId {
     Stack(StackPos), // place on stack
     Heap(HeapPos, u32), // allocated region + values within that region
+}
 /// Represents a value stored on the stack or on the heap. Some values contain
 /// a `HeapPos`, implying that they're stored in the store's `Heap`. Clearing
 /// a `Value` with a `HeapPos` from a stack must also clear the associated
 /// region from the `Heap`.
 #[derive(Debug, Clone)]
 pub enum Value {
     // Special types, never encountered during evaluation if the compiler works correctly
     Unassigned,                 // Marker when variables are first declared, immediately followed by assignment
     PrevStackBoundary(isize),   // Marker for stack frame beginning, so we can pop stack values
     Ref(ValueId),               // Reference to a value, used by expressions producing references
     Binding(StackPos),          // Reference to a binding variable (reserved on the stack)
     // Builtin types
     Input(PortId),
     Output(PortId),
     Message(HeapPos),
     Null,
     Bool(bool),
     Char(char),
     String(HeapPos),
     UInt8(u8),
     UInt16(u16),
     UInt32(u32),
     UInt64(u64),
     SInt8(i8),
     SInt16(i16),
     SInt32(i32),
     SInt64(i64),
     Array(HeapPos),
     // Instances of user-defined types
     Enum(i64),
     Union(i64, HeapPos),
     Struct(HeapPos),
+}
 macro_rules! impl_union_unpack_as_value {
     ($func_name:ident, $variant_name:path, $return_type:ty) => {
         impl Value {
             pub(crate) fn $func_name(&self) -> $return_type {
                 match self {
                     $variant_name(v) => *v,
                     _ => panic!(concat!("called ", stringify!($func_name()), " on {:?}"), self),
+                }
+            }
+        }
+    }
+}
 impl_union_unpack_as_value!(as_stack_boundary, Value::PrevStackBoundary, isize);
 impl_union_unpack_as_value!(as_ref,     Value::Ref,     ValueId);
 impl_union_unpack_as_value!(as_input,   Value::Input,   PortId);
 impl_union_unpack_as_value!(as_output,  Value::Output,  PortId);
 impl_union_unpack_as_value!(as_message, Value::Message, HeapPos);
 impl_union_unpack_as_value!(as_bool,    Value::Bool,    bool);
 impl_union_unpack_as_value!(as_char,    Value::Char,    char);
 impl_union_unpack_as_value!(as_string,  Value::String,  HeapPos);
 impl_union_unpack_as_value!(as_uint8,   Value::UInt8,   u8);
 impl_union_unpack_as_value!(as_uint16,  Value::UInt16,  u16);
 impl_union_unpack_as_value!(as_uint32,  Value::UInt32,  u32);
 impl_union_unpack_as_value!(as_uint64,  Value::UInt64,  u64);
 impl_union_unpack_as_value!(as_sint8,   Value::SInt8,   i8);
 impl_union_unpack_as_value!(as_sint16,  Value::SInt16,  i16);
 impl_union_unpack_as_value!(as_sint32,  Value::SInt32,  i32);
 impl_union_unpack_as_value!(as_sint64,  Value::SInt64,  i64);
 impl_union_unpack_as_value!(as_array,   Value::Array,   HeapPos);
 impl_union_unpack_as_value!(as_enum,    Value::Enum,    i64);
 impl_union_unpack_as_value!(as_struct,  Value::Struct,  HeapPos);
 impl Value {
     pub(crate) fn as_union(&self) -> (i64, HeapPos) {
         match self {
             Value::Union(tag, v) => (*tag, *v),
             _ => panic!("called as_union on {:?}", self),
+        }
+    }
     pub(crate) fn is_integer(&self) -> bool {
         match self {
             Value::UInt8(_) | Value::UInt16(_) | Value::UInt32(_) | Value::UInt64(_) |
             Value::SInt8(_) | Value::SInt16(_) | Value::SInt32(_) | Value::SInt64(_) => true,
             _ => false
+        }
+    }
     pub(crate) fn is_unsigned_integer(&self) -> bool {
         match self {
             Value::UInt8(_) | Value::UInt16(_) | Value::UInt32(_) | Value::UInt64(_) => true,
             _ => false
+        }
+    }
     pub(crate) fn is_signed_integer(&self) -> bool {
         match self {
             Value::SInt8(_) | Value::SInt16(_) | Value::SInt32(_) | Value::SInt64(_) => true,
             _ => false
+        }
+    }
     pub(crate) fn as_unsigned_integer(&self) -> u64 {
         match self {
             Value::UInt8(v)  => *v as u64,
             Value::UInt16(v) => *v as u64,
             Value::UInt32(v) => *v as u64,
             Value::UInt64(v) => *v as u64,
             _ => unreachable!("called as_unsigned_integer on {:?}", self),
+        }
+    }
     pub(crate) fn as_signed_integer(&self) -> i64 {
         match self {
             Value::SInt8(v)  => *v as i64,
             Value::SInt16(v) => *v as i64,
             Value::SInt32(v) => *v as i64,
             Value::SInt64(v) => *v as i64,
             _ => unreachable!("called as_signed_integer on {:?}", self)
+        }
+    }
     /// Returns the heap position associated with the value. If the value
     /// doesn't store anything in the heap then we return `None`.
     pub(crate) fn get_heap_pos(&self) -> Option<HeapPos> {
         match self {
             Value::Message(v) => Some(*v),
             Value::Array(v) => Some(*v),
             Value::Union(_, v) => Some(*v),
             Value::Struct(v) => Some(*v),
             _ => None
+        }
+    }
+}
 /// When providing arguments to a new component, or when transferring values
 /// from one component's store to a newly instantiated component, one has to
 /// transfer stack and heap values. This `ValueGroup` represents such a
 /// temporary group of values with potential heap allocations.
 ///
 /// Constructing such a ValueGroup manually requires some extra care to make
 /// sure all elements of `values` point to valid elements of `regions`.
 ///
 /// Again: this is a temporary thing, hopefully removed once we move to a
 /// bytecode interpreter.
 pub struct ValueGroup {
     pub(crate) values: Vec<Value>,
     pub(crate) regions: Vec<Vec<Value>>
+}
 impl ValueGroup {
     pub(crate) fn new_stack(values: Vec<Value>) -> Self {
         debug_assert!(values.iter().all(|v| v.get_heap_pos().is_none()));
         Self{
             values,
             regions: Vec::new(),
+        }
+    }
     pub(crate) fn from_store(store: &Store, values: &[Value]) -> Self {
         let mut group = ValueGroup{
             values: Vec::with_capacity(values.len()),
             regions: Vec::with_capacity(values.len()), // estimation
         };
         for value in values {
             let transferred = group.retrieve_value(value, store);
             group.values.push(transferred);
+        }
         group
+    }
     /// Transfers a provided value from a store into a local value with its
     /// heap allocations (if any) stored in the ValueGroup. Calling this
     /// function will not store the returned value in the `values` member.
     fn retrieve_value(&mut self, value: &Value, from_store: &Store) -> Value {
         let value = from_store.maybe_read_ref(value);
         if let Some(heap_pos) = value.get_heap_pos() {
             // Value points to a heap allocation, so transfer the heap values
             // internally.
             let from_region = &from_store.heap_regions[heap_pos as usize].values;
             let mut new_region = Vec::with_capacity(from_region.len());
             for value in from_region {
                 let transferred = self.retrieve_value(value, from_store);
                 new_region.push(transferred);
+            }
             // Region is constructed, store internally and return the new value.
             let new_region_idx = self.regions.len() as HeapPos;
             self.regions.push(new_region);
             return match value {
                 Value::Message(_)    => Value::Message(new_region_idx),
                 Value::String(_)     => Value::String(new_region_idx),
                 Value::Array(_)      => Value::Array(new_region_idx),
                 Value::Union(tag, _) => Value::Union(*tag, new_region_idx),
                 Value::Struct(_)     => Value::Struct(new_region_idx),
                 _ => unreachable!(),
             };
         } else {
             return value.clone();
+        }
+    }
     /// Transfers the heap values and the stack values into the store. Stack
     /// values are pushed onto the Store's stack in the order in which they
     /// appear in the value group.
     pub(crate) fn into_store(self, store: &mut Store) {
         for value in &self.values {
             let transferred = self.provide_value(value, store);
             store.stack.push(transferred);
+        }
+    }
     fn provide_value(&self, value: &Value, to_store: &mut Store) -> Value {
         if let Some(from_heap_pos) = value.get_heap_pos() {
             let from_heap_pos = from_heap_pos as usize;
             let to_heap_pos = to_store.alloc_heap();
             let to_heap_pos_usize = to_heap_pos as usize;
             to_store.heap_regions[to_heap_pos_usize].values.reserve(self.regions[from_heap_pos].len());
             for value in &self.regions[from_heap_pos as usize] {
                 let transferred = self.provide_value(value, to_store);
                 to_store.heap_regions[to_heap_pos_usize].values.push(transferred);
+            }
             return match value {
                 Value::Message(_)    => Value::Message(to_heap_pos),
                 Value::String(_)     => Value::String(to_heap_pos),
                 Value::Array(_)      => Value::Array(to_heap_pos),
                 Value::Union(tag, _) => Value::Union(*tag, to_heap_pos),
                 Value::Struct(_)     => Value::Struct(to_heap_pos),
                 _ => unreachable!(),
             };
         } else {
             return value.clone();
+        }
+    }
+}
 impl Default for ValueGroup {
     /// Returns an empty ValueGroup
     fn default() -> Self {
         Self { values: Vec::new(), regions: Vec::new() }
+    }
+}
 pub(crate) fn apply_assignment_operator(store: &mut Store, lhs: ValueId, op: AssignmentOperator, rhs: Value) {
     use AssignmentOperator as AO;
     macro_rules! apply_int_op {
         ($lhs:ident, $assignment_tokens:tt, $operator:ident, $rhs:ident) => {
             match $lhs {
                 Value::UInt8(v)  => { *v $assignment_tokens $rhs.as_uint8();  },
                 Value::UInt16(v) => { *v $assignment_tokens $rhs.as_uint16(); },
                 Value::UInt32(v) => { *v $assignment_tokens $rhs.as_uint32(); },
                 Value::UInt64(v) => { *v $assignment_tokens $rhs.as_uint64(); },
                 Value::SInt8(v)  => { *v $assignment_tokens $rhs.as_sint8();  },
                 Value::SInt16(v) => { *v $assignment_tokens $rhs.as_sint16(); },
                 Value::SInt32(v) => { *v $assignment_tokens $rhs.as_sint32(); },
                 Value::SInt64(v) => { *v $assignment_tokens $rhs.as_sint64(); },
                 _ => unreachable!("apply_assignment_operator {:?} on lhs {:?} and rhs {:?}", $operator, $lhs, $rhs),
+            }
+        }
+    }
     // let rhs = store.maybe_read_ref(&rhs).clone(); // we don't own this thing, so don't drop it
     let lhs = store.read_mut_ref(lhs);
     let mut to_dealloc = None;
     match op {
         AO::Set => {
             match lhs {
                 Value::Unassigned => { *lhs = rhs; },
                 Value::Input(v)  => { *v = rhs.as_input(); },
                 Value::Output(v) => { *v = rhs.as_output(); },
                 Value::Message(v)  => { to_dealloc = Some(*v); *v = rhs.as_message(); },
                 Value::Bool(v)    => { *v = rhs.as_bool(); },
                 Value::Char(v) => { *v = rhs.as_char(); },
                 Value::String(v) => { *v = rhs.as_string().clone(); },
                 Value::UInt8(v) => { *v = rhs.as_uint8(); },
                 Value::UInt16(v) => { *v = rhs.as_uint16(); },
                 Value::UInt32(v) => { *v = rhs.as_uint32(); },
                 Value::UInt64(v) => { *v = rhs.as_uint64(); },
                 Value::SInt8(v) => { *v = rhs.as_sint8(); },
                 Value::SInt16(v) => { *v = rhs.as_sint16(); },
                 Value::SInt32(v) => { *v = rhs.as_sint32(); },
                 Value::SInt64(v) => { *v = rhs.as_sint64(); },
                 Value::Array(v) => { to_dealloc = Some(*v); *v = rhs.as_array(); },
                 Value::Enum(v) => { *v = rhs.as_enum(); },
                 Value::Union(lhs_tag, lhs_heap_pos) => {
                     to_dealloc = Some(*lhs_heap_pos);
                     let (rhs_tag, rhs_heap_pos) = rhs.as_union();
                     *lhs_tag = rhs_tag;
                     *lhs_heap_pos = rhs_heap_pos;
+                }
                 Value::Struct(v) => { to_dealloc = Some(*v); *v = rhs.as_struct(); },
                 _ => unreachable!("apply_assignment_operator {:?} on lhs {:?} and rhs {:?}", op, lhs, rhs),
+            }
         },
         AO::Multiplied =>   { apply_int_op!(lhs, *=,  op, rhs) },
         AO::Divided =>      { apply_int_op!(lhs, /=,  op, rhs) },
         AO::Remained =>     { apply_int_op!(lhs, %=,  op, rhs) },
         AO::Added =>        { apply_int_op!(lhs, +=,  op, rhs) },
         AO::Subtracted =>   { apply_int_op!(lhs, -=,  op, rhs) },
         AO::ShiftedLeft =>  { apply_int_op!(lhs, <<=, op, rhs) },
         AO::ShiftedRight => { apply_int_op!(lhs, >>=, op, rhs) },
         AO::BitwiseAnded => { apply_int_op!(lhs, &=,  op, rhs) },
         AO::BitwiseXored => { apply_int_op!(lhs, ^=,  op, rhs) },
         AO::BitwiseOred =>  { apply_int_op!(lhs, |=,  op, rhs) },
+    }
     if let Some(heap_pos) = to_dealloc {
         store.drop_heap_pos(heap_pos);
+    }
+}
 pub(crate) fn apply_binary_operator(store: &mut Store, lhs: &Value, op: BinaryOperator, rhs: &Value) -> Value {
     use BinaryOperator as BO;
     macro_rules! apply_int_op_and_return_self {
         ($lhs:ident, $operator_tokens:tt, $operator:ident, $rhs:ident) => {
             return match $lhs {
                 Value::UInt8(v)  => { Value::UInt8( *v $operator_tokens $rhs.as_uint8() ) },
                 Value::UInt16(v) => { Value::UInt16(*v $operator_tokens $rhs.as_uint16()) },
                 Value::UInt32(v) => { Value::UInt32(*v $operator_tokens $rhs.as_uint32()) },
                 Value::UInt64(v) => { Value::UInt64(*v $operator_tokens $rhs.as_uint64()) },
                 Value::SInt8(v)  => { Value::SInt8( *v $operator_tokens $rhs.as_sint8() ) },
                 Value::SInt16(v) => { Value::SInt16(*v $operator_tokens $rhs.as_sint16()) },
                 Value::SInt32(v) => { Value::SInt32(*v $operator_tokens $rhs.as_sint32()) },
                 Value::SInt64(v) => { Value::SInt64(*v $operator_tokens $rhs.as_sint64()) },
                 _ => unreachable!("apply_binary_operator {:?} on lhs {:?} and rhs {:?}", $operator, $lhs, $rhs)
             };
+        }
+    }
     macro_rules! apply_int_op_and_return_bool {
         ($lhs:ident, $operator_tokens:tt, $operator:ident, $rhs:ident) => {
             return match $lhs {
                 Value::UInt8(v)  => { Value::Bool(*v $operator_tokens $rhs.as_uint8() ) },
                 Value::UInt16(v) => { Value::Bool(*v $operator_tokens $rhs.as_uint16()) },
                 Value::UInt32(v) => { Value::Bool(*v $operator_tokens $rhs.as_uint32()) },
                 Value::UInt64(v) => { Value::Bool(*v $operator_tokens $rhs.as_uint64()) },
                 Value::SInt8(v)  => { Value::Bool(*v $operator_tokens $rhs.as_sint8() ) },
                 Value::SInt16(v) => { Value::Bool(*v $operator_tokens $rhs.as_sint16()) },
                 Value::SInt32(v) => { Value::Bool(*v $operator_tokens $rhs.as_sint32()) },
                 Value::SInt64(v) => { Value::Bool(*v $operator_tokens $rhs.as_sint64()) },
                 _ => unreachable!("apply_binary_operator {:?} on lhs {:?} and rhs {:?}", $operator, $lhs, $rhs)
             };
+        }
+    }
     // We need to handle concatenate in a special way because it needs the store
     // mutably.
     if op == BO::Concatenate {
         let target_heap_pos = store.alloc_heap();
         let lhs_heap_pos;
         let rhs_heap_pos;
         let lhs = store.maybe_read_ref(lhs);
         let rhs = store.maybe_read_ref(rhs);
         enum ValueKind { Message, String, Array }
         let value_kind;
         match lhs {
             Value::Message(lhs_pos) => {
                 lhs_heap_pos = *lhs_pos;
                 rhs_heap_pos = rhs.as_message();
                 value_kind = ValueKind::Message;
             },
             Value::String(lhs_pos) => {
                 lhs_heap_pos = *lhs_pos;
                 rhs_heap_pos = rhs.as_string();
                 value_kind = ValueKind::String;
             },
             Value::Array(lhs_pos) => {
                 lhs_heap_pos = *lhs_pos;
                 rhs_heap_pos = rhs.as_array();
                 value_kind = ValueKind::Array;
             },
             _ => unreachable!("apply_binary_operator {:?} on lhs {:?} and rhs {:?}", op, lhs, rhs)
+        }
         let lhs_heap_pos = lhs_heap_pos as usize;
         let rhs_heap_pos = rhs_heap_pos as usize;
         // TODO: I hate this, but fine...
         let mut concatenated = Vec::new();
         let lhs_len = store.heap_regions[lhs_heap_pos].values.len();
         let rhs_len = store.heap_regions[rhs_heap_pos].values.len();
         concatenated.reserve(lhs_len + rhs_len);
         for idx in 0..lhs_len {
             concatenated.push(store.clone_value(store.heap_regions[lhs_heap_pos].values[idx].clone()));
+        }
         for idx in 0..rhs_len {
             concatenated.push(store.clone_value(store.heap_regions[rhs_heap_pos].values[idx].clone()));
+        }
         store.heap_regions[target_heap_pos as usize].values = concatenated;
         return match value_kind{
             ValueKind::Message => Value::Message(target_heap_pos),
             ValueKind::String => Value::String(target_heap_pos),
             ValueKind::Array => Value::Array(target_heap_pos),
         };
+    }
     // If any of the values are references, retrieve the thing they're referring
     // to.
     let lhs = store.maybe_read_ref(lhs);
     let rhs = store.maybe_read_ref(rhs);
     match op {
         BO::Concatenate => unreachable!(),
         BO::LogicalOr => {
             return Value::Bool(lhs.as_bool() || rhs.as_bool());
         },
         BO::LogicalAnd => {
             return Value::Bool(lhs.as_bool() && rhs.as_bool());
         },
         BO::BitwiseOr        => { apply_int_op_and_return_self!(lhs, |,  op, rhs); },
         BO::BitwiseXor       => { apply_int_op_and_return_self!(lhs, ^,  op, rhs); },
         BO::BitwiseAnd       => { apply_int_op_and_return_self!(lhs, &,  op, rhs); },
         BO::Equality         => { Value::Bool(apply_equality_operator(store, lhs, rhs)) },
         BO::Inequality       => { Value::Bool(apply_inequality_operator(store, lhs, rhs)) },
         BO::LessThan         => { apply_int_op_and_return_bool!(lhs, <,  op, rhs); },
         BO::GreaterThan      => { apply_int_op_and_return_bool!(lhs, >,  op, rhs); },
         BO::LessThanEqual    => { apply_int_op_and_return_bool!(lhs, <=, op, rhs); },
         BO::GreaterThanEqual => { apply_int_op_and_return_bool!(lhs, >=, op, rhs); },
         BO::ShiftLeft        => { apply_int_op_and_return_self!(lhs, <<, op, rhs); },
         BO::ShiftRight       => { apply_int_op_and_return_self!(lhs, >>, op, rhs); },
         BO::Add              => { apply_int_op_and_return_self!(lhs, +,  op, rhs); },
         BO::Subtract         => { apply_int_op_and_return_self!(lhs, -,  op, rhs); },
         BO::Multiply         => { apply_int_op_and_return_self!(lhs, *,  op, rhs); },
         BO::Divide           => { apply_int_op_and_return_self!(lhs, /,  op, rhs); },
         BO::Remainder        => { apply_int_op_and_return_self!(lhs, %,  op, rhs); }
+    }
+}
 pub(crate) fn apply_unary_operator(store: &mut Store, op: UnaryOperator, value: &Value) -> Value {
     use UnaryOperator as UO;
     macro_rules! apply_int_expr_and_return {
         ($value:ident, $apply:tt, $op:ident) => {
             return match $value {
                 Value::UInt8(v)  => Value::UInt8($apply *v),
                 Value::UInt16(v) => Value::UInt16($apply *v),
                 Value::UInt32(v) => Value::UInt32($apply *v),
                 Value::UInt64(v) => Value::UInt64($apply *v),
                 Value::SInt8(v)  => Value::SInt8($apply *v),
                 Value::SInt16(v) => Value::SInt16($apply *v),
                 Value::SInt32(v) => Value::SInt32($apply *v),
                 Value::SInt64(v) => Value::SInt64($apply *v),
                 _ => unreachable!("apply_unary_operator {:?} on value {:?}", $op, $value),
             };
+        }
+    }
     // If the value is a reference, retrieve the thing it is referring to
     let value = store.maybe_read_ref(value);
     match op {
         UO::Positive => {
             debug_assert!(value.is_integer());
             return value.clone();
         },
         UO::Negative => {
             // TODO: Error on negating unsigned integers
             return match value {
                 Value::SInt8(v) => Value::SInt8(-*v),
                 Value::SInt16(v) => Value::SInt16(-*v),
                 Value::SInt32(v) => Value::SInt32(-*v),
                 Value::SInt64(v) => Value::SInt64(-*v),
                 _ => unreachable!("apply_unary_operator {:?} on value {:?}", op, value),
+            }
         },
         UO::BitwiseNot => { apply_int_expr_and_return!(value, !, op)},
         UO::LogicalNot => { return Value::Bool(!value.as_bool()); },
         UO::PreIncrement => { todo!("implement") },
         UO::PreDecrement => { todo!("implement") },
         UO::PostIncrement => { todo!("implement") },
         UO::PostDecrement => { todo!("implement") },
+    }
+}
 pub(crate) fn apply_casting(store: &mut Store, output_type: &ConcreteType, subject: &Value) -> Result<Value, String> {
     // To simplify the casting logic: if the output type is not a simple
     // integer/boolean/character, then the type checker made sure that the two
     // types must be equal, hence we can do a simple clone.
     use ConcreteTypePart as CTP;
     let part = &output_type.parts[0];
     match part {
         CTP::Bool | CTP::Character |
         CTP::UInt8 | CTP::UInt16 | CTP::UInt32 | CTP::UInt64 |
         CTP::SInt8 | CTP::SInt16 | CTP::SInt32 | CTP::SInt64 => {
             // Do the checking of these below
             debug_assert_eq!(output_type.parts.len(), 1);
         },
         _ => {
             return Ok(store.clone_value(subject.clone()));
         },
+    }
     // Note: character is not included, needs per-type checking
     macro_rules! unchecked_cast {
         ($input: expr, $output_part: expr) => {
             return Ok(match $output_part {
                 CTP::UInt8 => Value::UInt8($input as u8),
                 CTP::UInt16 => Value::UInt16($input as u16),
                 CTP::UInt32 => Value::UInt32($input as u32),
                 CTP::UInt64 => Value::UInt64($input as u64),
                 CTP::SInt8 => Value::SInt8($input as i8),
                 CTP::SInt16 => Value::SInt16($input as i16),
                 CTP::SInt32 => Value::SInt32($input as i32),
                 CTP::SInt64 => Value::SInt64($input as i64),
                 _ => unreachable!()
             })
+        }
+    }
     macro_rules! from_unsigned_cast {
         ($input:expr, $input_type:ty, $output_part:expr) => {
+            {
                 let target_type_name = match $output_part {
                     CTP::Bool => return Ok(Value::Bool($input != 0)),
                     CTP::Character => if $input <= u8::MAX as $input_type {
                         return Ok(Value::Char(($input as u8) as char))
                     } else {
                         KW_TYPE_CHAR_STR
                     },
                     CTP::UInt8 => if $input <= u8::MAX as $input_type {
                         return Ok(Value::UInt8($input as u8))
                     } else {
                         KW_TYPE_UINT8_STR
                     },
                     CTP::UInt16 => if $input <= u16::MAX as $input_type {
                         return Ok(Value::UInt16($input as u16))
                     } else {
                         KW_TYPE_UINT16_STR
                     },
                     CTP::UInt32 => if $input <= u32::MAX as $input_type {
                         return Ok(Value::UInt32($input as u32))
                     } else {
                         KW_TYPE_UINT32_STR
                     },
                     CTP::UInt64 => return Ok(Value::UInt64($input as u64)), // any unsigned int to u64 is fine
                     CTP::SInt8 => if $input <= i8::MAX as $input_type {
                         return Ok(Value::SInt8($input as i8))
                     } else {
                         KW_TYPE_SINT8_STR
                     },
                     CTP::SInt16 => if $input <= i16::MAX as $input_type {
                         return Ok(Value::SInt16($input as i16))
                     } else {
                         KW_TYPE_SINT16_STR
                     },
                     CTP::SInt32 => if $input <= i32::MAX as $input_type {
                         return Ok(Value::SInt32($input as i32))
                     } else {
                         KW_TYPE_SINT32_STR
                     },
                     CTP::SInt64 => if $input <= i64::MAX as $input_type {
                         return Ok(Value::SInt64($input as i64))
                     } else {
                         KW_TYPE_SINT64_STR
                     },
                     _ => unreachable!(),
                 };
                 return Err(format!("value is '{}' which doesn't fit in a type '{}'", $input, target_type_name));
+            }
+        }
+    }
     macro_rules! from_signed_cast {
         // Programmer note: for signed checking we cannot do
         //  output_type::MAX as input_type,
         //
         // because if the output type's width is larger than the input type,
         // then the cast results in a negative number. So we mask with the
         // maximum possible value the input type can become. As in:
         //  (output_type::MAX as input_type) & input_type::MAX
         //
         // This way:
         // 1. output width is larger than input width: fine in all cases, we
         //  simply compare against the max input value, which is always true.
         // 2. output width is equal to input width: by masking we "remove the
         //  signed bit from the unsigned number" and again compare against the
         //  maximum input value.
         // 3. output width is smaller than the input width: masking does nothing
         //  because the signed bit is never set, and we simply compare against
         //  the maximum possible output value.
         //
         // A similar kind of mechanism for the minimum value, but here we do
         // a binary OR. We do a:
         //  (output_type::MIN as input_type) & input_type::MIN
         //
         // This way:
         // 1. output width is larger than input width: initial cast truncates to
         //  0, then we OR with the actual minimum value, so we attain the
         //  minimum value of the input type.
         // 2. output width is equal to input width: we OR the minimum value with
         //  itself.
         // 3. output width is smaller than input width: the cast produces the
         //  min value of the output type, the subsequent OR does nothing, as it
         //  essentially just sets the signed bit (which must already be set,
         //  since we're dealing with a signed minimum value)
         //
         // After all of this expanding, we simply hope the compiler does a best
         // effort constant expression evaluation, and presto!
         ($input:expr, $input_type:ty, $output_type:expr) => {
+            {
                 let target_type_name = match $output_type {
                     CTP::Bool => return Ok(Value::Bool($input != 0)),
                     CTP::Character => if $input >= 0 && $input <= (u8::max as $input_type & <$input_type>::MAX) {
                         return Ok(Value::Char(($input as u8) as char))
                     } else {
                         KW_TYPE_CHAR_STR
                     },
                     CTP::UInt8 => if $input >= 0 && $input <= ((u8::MAX as $input_type) & <$input_type>::MAX) {
                         return Ok(Value::UInt8($input as u8));
                     } else {
                         KW_TYPE_UINT8_STR
                     },
                     CTP::UInt16 => if $input >= 0 && $input <= ((u16::MAX as $input_type) & <$input_type>::MAX) {
                         return Ok(Value::UInt16($input as u16));
                     } else {
                         KW_TYPE_UINT16_STR
                     },
                     CTP::UInt32 => if $input >= 0 && $input <= ((u32::MAX as $input_type) & <$input_type>::MAX) {
                         return Ok(Value::UInt32($input as u32));
                     } else {
                         KW_TYPE_UINT32_STR
                     },
                     CTP::UInt64 => if $input >= 0 && $input <= ((u64::MAX as $input_type) & <$input_type>::MAX) {
                         return Ok(Value::UInt64($input as u64));
                     } else {
                         KW_TYPE_UINT64_STR
                     },
                     CTP::SInt8 => if $input >= ((i8::MIN as $input_type) | <$input_type>::MIN) && $input <= ((i8::MAX as $input_type) & <$input_type>::MAX) {
                         return Ok(Value::SInt8($input as i8));
                     } else {
                         KW_TYPE_SINT8_STR
                     },
                     CTP::SInt16 => if $input >= ((i16::MIN as $input_type | <$input_type>::MIN)) && $input <= ((i16::MAX as $input_type) & <$input_type>::MAX) {
                         return Ok(Value::SInt16($input as i16));
                     } else {
                         KW_TYPE_SINT16_STR
                     },
                     CTP::SInt32 => if $input >= ((i32::MIN as $input_type | <$input_type>::MIN)) && $input <= ((i32::MAX as $input_type) & <$input_type>::MAX) {
                         return Ok(Value::SInt32($input as i32));
                     } else {
                         KW_TYPE_SINT32_STR
                     },
                     CTP::SInt64 => return Ok(Value::SInt64($input as i64)),
                     _ => unreachable!(),
                 };
                 return Err(format!("value is '{}' which doesn't fit in a type '{}'", $input, target_type_name));
+            }
+        }
+    }
     // If here, then the types might still be equal, but at least we're dealing
     // with a simple integer/boolean/character input and output type.
     let subject = store.maybe_read_ref(subject);
     match subject {
         Value::Bool(val) => {
             match part {
                 CTP::Bool => return Ok(Value::Bool(*val)),
                 CTP::Character => return Ok(Value::Char(1 as char)),
                 _ => unchecked_cast!(*val, part),
+            }
         },
         Value::Char(val) => {
             match part {
                 CTP::Bool => return Ok(Value::Bool(*val != 0 as char)),
                 CTP::Character => return Ok(Value::Char(*val)),
                 _ => unchecked_cast!(*val, part),
+            }
         },
         Value::UInt8(val) => from_unsigned_cast!(*val, u8, part),
         Value::UInt16(val) => from_unsigned_cast!(*val, u16, part),
         Value::UInt32(val) => from_unsigned_cast!(*val, u32, part),
         Value::UInt64(val) => from_unsigned_cast!(*val, u64, part),
         Value::SInt8(val) => from_signed_cast!(*val, i8, part),
         Value::SInt16(val) => from_signed_cast!(*val, i16, part),
         Value::SInt32(val) => from_signed_cast!(*val, i32, part),
         Value::SInt64(val) => from_signed_cast!(*val, i64, part),
         _ => unreachable!("mismatch between 'cast' type checking and 'cast' evaluation"),
+    }
+}
 /// Recursively checks for equality.
 pub(crate) fn apply_equality_operator(store: &Store, lhs: &Value, rhs: &Value) -> bool {
     let lhs = store.maybe_read_ref(lhs);
     let rhs = store.maybe_read_ref(rhs);
     fn eval_equality_heap(store: &Store, lhs_pos: HeapPos, rhs_pos: HeapPos) -> bool {
         let lhs_vals = &store.heap_regions[lhs_pos as usize].values;
         let rhs_vals = &store.heap_regions[rhs_pos as usize].values;
         let lhs_len = lhs_vals.len();
         if lhs_len != rhs_vals.len() {
             return false;
+        }
         for idx in 0..lhs_len {
             let lhs_val = &lhs_vals[idx];
             let rhs_val = &rhs_vals[idx];
             if !apply_equality_operator(store, lhs_val, rhs_val) {
                 return false;
+            }
+        }
         return true;
+    }
     match lhs {
         Value::Input(v) => *v == rhs.as_input(),
         Value::Output(v) => *v == rhs.as_output(),
         Value::Message(lhs_pos) => eval_equality_heap(store, *lhs_pos, rhs.as_message()),
         Value::Null => todo!("remove null"),
         Value::Bool(v) => *v == rhs.as_bool(),
         Value::Char(v) => *v == rhs.as_char(),
         Value::String(lhs_pos) => eval_equality_heap(store, *lhs_pos, rhs.as_string()),
         Value::UInt8(v) => *v == rhs.as_uint8(),
         Value::UInt16(v) => *v == rhs.as_uint16(),
         Value::UInt32(v) => *v == rhs.as_uint32(),
         Value::UInt64(v) => *v == rhs.as_uint64(),
         Value::SInt8(v) => *v == rhs.as_sint8(),
         Value::SInt16(v) => *v == rhs.as_sint16(),
         Value::SInt32(v) => *v == rhs.as_sint32(),
         Value::SInt64(v) => *v == rhs.as_sint64(),
         Value::Array(lhs_pos) => eval_equality_heap(store, *lhs_pos, rhs.as_array()),
         Value::Enum(v) => *v == rhs.as_enum(),
         Value::Union(lhs_tag, lhs_pos) => {
             let (rhs_tag, rhs_pos) = rhs.as_union();
             if *lhs_tag != rhs_tag {
                 return false;
+            }
             eval_equality_heap(store, *lhs_pos, rhs_pos)
         },
         Value::Struct(lhs_pos) => eval_equality_heap(store, *lhs_pos, rhs.as_struct()),
         _ => unreachable!("apply_equality_operator to lhs {:?}", lhs),
+    }
+}
 /// Recursively checks for inequality
 pub(crate) fn apply_inequality_operator(store: &Store, lhs: &Value, rhs: &Value) -> bool {
     let lhs = store.maybe_read_ref(lhs);
     let rhs = store.maybe_read_ref(rhs);
     fn eval_inequality_heap(store: &Store, lhs_pos: HeapPos, rhs_pos: HeapPos) -> bool {
         let lhs_vals = &store.heap_regions[lhs_pos as usize].values;
         let rhs_vals = &store.heap_regions[rhs_pos as usize].values;
         let lhs_len = lhs_vals.len();
         if lhs_len != rhs_vals.len() {
             return true;
+        }
         for idx in 0..lhs_len {
             let lhs_val = &lhs_vals[idx];
             let rhs_val = &rhs_vals[idx];
             if apply_inequality_operator(store, lhs_val, rhs_val) {
                 return true;
+            }
+        }
         return false;
+    }
     match lhs {
         Value::Input(v) => *v != rhs.as_input(),
         Value::Output(v) => *v != rhs.as_output(),
         Value::Message(lhs_pos) => eval_inequality_heap(store, *lhs_pos, rhs.as_message()),
         Value::Null => todo!("remove null"),
         Value::Bool(v) => *v != rhs.as_bool(),
         Value::Char(v) => *v != rhs.as_char(),
         Value::String(lhs_pos) => eval_inequality_heap(store, *lhs_pos, rhs.as_string()),
         Value::UInt8(v) => *v != rhs.as_uint8(),
         Value::UInt16(v) => *v != rhs.as_uint16(),
         Value::UInt32(v) => *v != rhs.as_uint32(),
         Value::UInt64(v) => *v != rhs.as_uint64(),
         Value::SInt8(v) => *v != rhs.as_sint8(),
         Value::SInt16(v) => *v != rhs.as_sint16(),
         Value::SInt32(v) => *v != rhs.as_sint32(),
         Value::SInt64(v) => *v != rhs.as_sint64(),
         Value::Enum(v) => *v != rhs.as_enum(),
         Value::Union(lhs_tag, lhs_pos) => {
             let (rhs_tag, rhs_pos) = rhs.as_union();
             if *lhs_tag != rhs_tag {
                 return true;
+            }
             eval_inequality_heap(store, *lhs_pos, rhs_pos)
         },
         Value::String(lhs_pos) => eval_inequality_heap(store, *lhs_pos, rhs.as_struct()),
         _ => unreachable!("apply_inequality_operator to lhs {:?}", lhs)
+    }
+}
 /// Recursively applies binding operator. Essentially an equality operator with
 /// special handling if the LHS contains a binding reference to a stack
 /// stack variable.
 // Note: that there is a lot of `Value.clone()` going on here. As always: this
 // is potentially cloning the references to heap values, not actually cloning
 // those heap regions into a new heap region.
 pub(crate) fn apply_binding_operator(store: &mut Store, lhs: Value, rhs: Value) -> bool {
     let lhs = store.maybe_read_ref(&lhs).clone();
     let rhs = store.maybe_read_ref(&rhs).clone();
     fn eval_binding_heap(store: &mut Store, lhs_pos: HeapPos, rhs_pos: HeapPos) -> bool {
         let lhs_len = store.heap_regions[lhs_pos as usize].values.len();
         let rhs_len = store.heap_regions[rhs_pos as usize].values.len();
         if lhs_len != rhs_len {
             return false;
+        }
         for idx in 0..lhs_len {
             // More rust shenanigans... I'm going to calm myself by saying that
             // this is just a temporary evaluator implementation.
             let lhs_val = store.heap_regions[lhs_pos as usize].values[idx].clone();
             let rhs_val = store.heap_regions[rhs_pos as usize].values[idx].clone();
             if !apply_binding_operator(store, lhs_val, rhs_val) {
                 return false;
+            }
+        }
         return true;
+    }
     match lhs {
         Value::Binding(var_pos) => {
             let to_write = store.clone_value(rhs.clone());
             store.write(ValueId::Stack(var_pos), to_write);
             return true;
         },
         Value::Input(v) => v == rhs.as_input(),
         Value::Output(v) => v == rhs.as_output(),
         Value::Message(lhs_pos) => eval_binding_heap(store, lhs_pos, rhs.as_message()),
         Value::Null => todo!("remove null"),
         Value::Bool(v) => v == rhs.as_bool(),
         Value::Char(v) => v == rhs.as_char(),
         Value::String(lhs_pos) => eval_binding_heap(store, lhs_pos, rhs.as_string()),
         Value::UInt8(v) => v == rhs.as_uint8(),
         Value::UInt16(v) => v == rhs.as_uint16(),
         Value::UInt32(v) => v == rhs.as_uint32(),
         Value::UInt64(v) => v == rhs.as_uint64(),
         Value::SInt8(v) => v == rhs.as_sint8(),
         Value::SInt16(v) => v == rhs.as_sint16(),
         Value::SInt32(v) => v == rhs.as_sint32(),
         Value::SInt64(v) => v == rhs.as_sint64(),
         Value::Array(lhs_pos) => eval_binding_heap(store, lhs_pos, rhs.as_array()),
         Value::Enum(v) => v == rhs.as_enum(),
         Value::Union(lhs_tag, lhs_pos) => {
             let (rhs_tag, rhs_pos) = rhs.as_union();
             if lhs_tag != rhs_tag {
                 return false;
+            }
             eval_binding_heap(store, lhs_pos, rhs_pos)
         },
         Value::Struct(lhs_pos) => eval_binding_heap(store, lhs_pos, rhs.as_struct()),
         _ => unreachable!("apply_binding_operator to lhs {:?}", lhs),
+    }
+}
@@ \ No newline at end of file @@

src/protocol/mod.rs

➞

Show inline comments

 mod arena;
 mod eval;
 pub(crate) mod input_source;
 mod parser;
 #[cfg(test)] mod tests;
 pub(crate) mod ast;
 pub(crate) mod ast_printer;
 use std::sync::Mutex;
 use crate::collections::{StringPool, StringRef};
 use crate::common::*;
 use crate::protocol::ast::*;
 use crate::protocol::eval::*;
 use crate::protocol::input_source::*;
 use crate::protocol::parser::*;
 use crate::protocol::type_table::*;
 /// 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 {
     modules: Vec<Module>,
     heap: Heap,
     types: TypeTable,
     pool: Mutex<StringPool>,
+}
 #[derive(Debug, Clone)]
 pub(crate) struct ComponentState {
     prompt: Prompt,
+}
 pub(crate) enum EvalContext<'a> {
     Nonsync(&'a mut NonsyncProtoContext<'a>),
     Sync(&'a mut SyncProtoContext<'a>),
     None,
+}
 //////////////////////////////////////////////
 impl std::fmt::Debug for ProtocolDescription {
     fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
         write!(f, "(An opaque protocol description)")
+    }
+}
 impl ProtocolDescription {
     // TODO: Allow for multi-file compilation
     pub fn parse(buffer: &[u8]) -> Result<Self, String> {
         // TODO: @fixme, keep code compilable, but needs support for multiple
         //  input files.
         let source = InputSource::new(String::new(), Vec::from(buffer));
         let mut parser = Parser::new();
         parser.feed(source).expect("failed to feed source");
         if let Err(err) = parser.parse() {
             println!("ERROR:\n{}", err);
             return Err(format!("{}", err))
+        }
         debug_assert_eq!(parser.modules.len(), 1, "only supporting one module here for now");
         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 component_polarities(
         &self,
         module_name: &[u8],
         identifier: &[u8],
     ) -> Result<Vec<Polarity>, AddComponentError> {
         use AddComponentError::*;
         let module_root = self.lookup_module_root(module_name);
         if module_root.is_none() {
             return Err(AddComponentError::NoSuchModule);
+        }
         let module_root = module_root.unwrap();
         let root = &self.heap[module_root];
         let def = root.get_definition_ident(&self.heap, identifier);
         if def.is_none() {
             return Err(NoSuchComponent);
+        }
         let def = &self.heap[def.unwrap()];
         if !def.is_component() {
             return Err(NoSuchComponent);
+        }
         for &param in def.parameters().iter() {
             let param = &self.heap[param];
             let first_element = &param.parser_type.elements[0];
             match first_element.variant {
                 ParserTypeVariant::Input | ParserTypeVariant::Output => continue,
                 _ => {
                     return Err(NonPortTypeParameters);
+                }
+            }
+        }
         let mut result = Vec::new();
         for &param in def.parameters().iter() {
             let param = &self.heap[param];
             let first_element = &param.parser_type.elements[0];
             if first_element.variant == ParserTypeVariant::Input {
                 result.push(Polarity::Getter)
             } else if first_element.variant == ParserTypeVariant::Output {
                 result.push(Polarity::Putter)
             } else {
                 unreachable!()
+            }
+        }
         Ok(result)
+    }
     // expects port polarities to be correct
     pub(crate) fn new_component(&self, module_name: &[u8], identifier: &[u8], ports: &[PortId]) -> ComponentState {
         let mut args = Vec::new();
         for (&x, y) in ports.iter().zip(self.component_polarities(module_name, identifier).unwrap()) {
             match y {
                 Polarity::Getter => args.push(Value::Input(x)),
                 Polarity::Putter => args.push(Value::Output(x)),
+            }
+        }
         let module_root = self.lookup_module_root(module_name).unwrap();
         let root = &self.heap[module_root];
         let def = root.get_definition_ident(&self.heap, identifier).unwrap();
         ComponentState { prompt: Prompt::new(&self.types, &self.heap, def, 0, ValueGroup::new_stack(args)) }
+    }
     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;
+    }
+}
 impl ComponentState {
     pub(crate) fn nonsync_run<'a: 'b, 'b>(
         &'a mut self,
         context: &'b mut NonsyncProtoContext<'b>,
         pd: &'a ProtocolDescription,
     ) -> NonsyncBlocker {
         let mut context = EvalContext::Nonsync(context);
         loop {
             let result = self.prompt.step(&pd.types, &pd.heap, &pd.modules, &mut context);
             match result {
                 Err(err) => {
                     println!("Evaluation error:\n{}", err);
                     panic!("proper error handling when component fails");
                 },
                 Ok(cont) => match cont {
                     EvalContinuation::Stepping => continue,
                     EvalContinuation::Inconsistent => return NonsyncBlocker::Inconsistent,
                     EvalContinuation::Terminal => return NonsyncBlocker::ComponentExit,
                     EvalContinuation::SyncBlockStart => return NonsyncBlocker::SyncBlockStart,
                     // Not possible to end sync block if never entered one
                     EvalContinuation::SyncBlockEnd => unreachable!(),
                     EvalContinuation::NewComponent(definition_id, monomorph_idx, args) => {
                         // Look up definition (TODO for now, assume it is a definition)
                         let mut moved_ports = HashSet::new();
                         for arg in args.values.iter() {
                             match arg {
                                 Value::Output(port) => {
                                     moved_ports.insert(*port);
+                                }
                                 Value::Input(port) => {
                                     moved_ports.insert(*port);
+                                }
                                 _ => {}
+                            }
+                        }
                         for region in args.regions.iter() {
                             for arg in region {
                                 match arg {
                                     Value::Output(port) => { moved_ports.insert(*port); },
                                     Value::Input(port) => { moved_ports.insert(*port); },
                                     _ => {},
+                                }
+                            }
+                        }
                         let init_state = ComponentState { prompt: Prompt::new(&pd.types, &pd.heap, definition_id, monomorph_idx, args) };
                         context.new_component(moved_ports, init_state);
                         // Continue stepping
                         continue;
+                    }
                     // Outside synchronous blocks, no fires/get/put happens
                     EvalContinuation::BlockFires(_) => unreachable!(),
                     EvalContinuation::BlockGet(_) => unreachable!(),
                     EvalContinuation::Put(_, _) => unreachable!(),
                 },
+            }
+        }
+    }
     pub(crate) fn sync_run<'a: 'b, 'b>(
         &'a mut self,
         context: &'b mut SyncProtoContext<'b>,
         pd: &'a ProtocolDescription,
     ) -> SyncBlocker {
         let mut context = EvalContext::Sync(context);
         loop {
             let result = self.prompt.step(&pd.types, &pd.heap, &pd.modules, &mut context);
             match result {
                 Err(err) => {
                     println!("Evaluation error:\n{}", err);
                     panic!("proper error handling when component fails");
                 },
                 Ok(cont) => match cont {
                     EvalContinuation::Stepping => continue,
                     EvalContinuation::Inconsistent => return SyncBlocker::Inconsistent,
                     // First need to exit synchronous block before definition may end
                     EvalContinuation::Terminal => unreachable!(),
                     // No nested synchronous blocks
                     EvalContinuation::SyncBlockStart => unreachable!(),
                     EvalContinuation::SyncBlockEnd => return SyncBlocker::SyncBlockEnd,
                     // Not possible to create component in sync block
                     EvalContinuation::NewComponent(_, _, _) => unreachable!(),
                     EvalContinuation::BlockFires(port) => match port {
                         Value::Output(port) => {
                             return SyncBlocker::CouldntCheckFiring(port);
+                        }
                         Value::Input(port) => {
                             return SyncBlocker::CouldntCheckFiring(port);
+                        }
                         _ => unreachable!(),
                     },
                     EvalContinuation::BlockGet(port) => match port {
                         Value::Output(port) => {
                             return SyncBlocker::CouldntReadMsg(port);
+                        }
                         Value::Input(port) => {
                             return SyncBlocker::CouldntReadMsg(port);
+                        }
                         _ => unreachable!(),
                     },
                     EvalContinuation::Put(port, message) => {
                         let value;
                         match port {
                             Value::Output(port_value) => {
                                 value = port_value;
+                            }
                             Value::Input(port_value) => {
                                 value = port_value;
+                            }
                             _ => unreachable!(),
+                        }
                         let payload;
                         match message {
                             Value::Null => {
                                 return SyncBlocker::Inconsistent;
                             },
                             Value::Message(heap_pos) => {
                                 // Create a copy of the payload
                                 let values = &self.prompt.store.heap_regions[heap_pos as usize].values;
                                 let mut bytes = Vec::with_capacity(values.len());
                                 for value in values {
                                     bytes.push(value.as_uint8());
+                                }
                                 payload = Payload(Arc::new(bytes));
+                            }
                             _ => unreachable!(),
+                        }
                         return SyncBlocker::PutMsg(value, payload);
+                    }
                 },
+            }
+        }
+    }
+}
 impl EvalContext<'_> {
     // fn random(&mut self) -> LongValue {
     //     match self {
     //         // EvalContext::None => unreachable!(),
     //         EvalContext::Nonsync(_context) => todo!(),
     //         EvalContext::Sync(_) => unreachable!(),
     //     }
     // }
     fn new_component(&mut self, moved_ports: HashSet<PortId>, init_state: ComponentState) -> () {
         match self {
             EvalContext::None => unreachable!(),
             EvalContext::Nonsync(context) => {
                 context.new_component(moved_ports, init_state)
+            }
             EvalContext::Sync(_) => unreachable!(),
+        }
+    }
     fn new_channel(&mut self) -> [Value; 2] {
         match self {
             EvalContext::None => unreachable!(),
             EvalContext::Nonsync(context) => {
                 let [from, to] = context.new_port_pair();
                 let from = Value::Output(from);
                 let to = Value::Input(to);
                 return [from, to];
+            }
             EvalContext::Sync(_) => unreachable!(),
+        }
+    }
     fn fires(&mut self, port: Value) -> Option<Value> {
         match self {
             EvalContext::None => unreachable!(),
             EvalContext::Nonsync(_) => unreachable!(),
             EvalContext::Sync(context) => match port {
                 Value::Output(port) => context.is_firing(port).map(Value::Bool),
                 Value::Input(port) => context.is_firing(port).map(Value::Bool),
                 _ => unreachable!(),
             },
+        }
+    }
     fn get(&mut self, port: Value, store: &mut Store) -> Option<Value> {
         match self {
             EvalContext::None => unreachable!(),
             EvalContext::Nonsync(_) => unreachable!(),
             EvalContext::Sync(context) => match port {
                 Value::Output(port) => {
                     debug_assert!(false, "Getting from an output port? Am I mad?");
                     unreachable!();
+                }
                 Value::Input(port) => {
                     let heap_pos = store.alloc_heap();
                     let heap_pos_usize = heap_pos as usize;
                     let payload = context.read_msg(port);
                     if payload.is_none() { return None; }
                     let heap_pos = store.alloc_heap();
                     let heap_pos_usize = heap_pos as usize;
                     let payload = payload.unwrap();
                     store.heap_regions[heap_pos_usize].values.reserve(payload.0.len());
                     for value in payload.0.iter() {
                         store.heap_regions[heap_pos_usize].values.push(Value::UInt8(*value));
+                    }
                     return Some(Value::Message(heap_pos));
+                }
                 _ => unreachable!(),
             },
+        }
+    }
     fn did_put(&mut self, port: Value) -> bool {
         match self {
             EvalContext::None => unreachable!("did_put in None context"),
             EvalContext::Nonsync(_) => unreachable!("did_put in nonsync context"),
             EvalContext::Sync(context) => match port {
                 Value::Output(port) => {
                     context.did_put_or_get(port)
                 },
                 Value::Input(_) => unreachable!("did_put on input port"),
                 _ => unreachable!("did_put on non-port value")
+            }
+        }
+    }
+}

src/protocol/parser/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 crate::protocol::input_source::{InputSource as InputSource, InputPosition as 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,
     // 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(),
             buffer: String::with_capacity(128),
             struct_fields: ScopedBuffer::new_reserved(128),
             enum_variants: ScopedBuffer::new_reserved(128),
             union_variants: ScopedBuffer::new_reserved(128),
             variables: ScopedBuffer::new_reserved(128),
             expressions: ScopedBuffer::new_reserved(128),
             statements: ScopedBuffer::new_reserved(128),
             parser_types: ScopedBuffer::new_reserved(128),
+        }
+    }
     pub(crate) fn parse(&mut self, modules: &mut [Module], module_idx: usize, ctx: &mut PassCtx) -> Result<(), ParseError> {
         let module = &modules[module_idx];
         let module_range = &module.tokens.ranges[0];
         debug_assert_eq!(module.phase, ModuleCompilationPhase::ImportsResolved);
         debug_assert_eq!(module_range.range_kind, TokenRangeKind::Module);
         // Although we only need to parse the definitions, we want to go through
         // code ranges as well such that we can throw errors if we get
         // unexpected tokens at the module level of the source.
         let mut range_idx = module_range.first_child_idx;
         loop {
             let range_idx_usize = range_idx as usize;
             let cur_range = &module.tokens.ranges[range_idx_usize];
             match cur_range.range_kind {
                 TokenRangeKind::Module => unreachable!(), // should not be reachable
                 TokenRangeKind::Pragma | TokenRangeKind::Import => {
                     // Already fully parsed, fall through and go to next range
                 },
                 TokenRangeKind::Definition | TokenRangeKind::Code => {
                     // Visit range even if it is a "code" range to provide
                     // proper error messages.
                     self.visit_range(modules, module_idx, ctx, range_idx_usize)?;
                 },
+            }
             if cur_range.next_sibling_idx == NO_SIBLING {
                 break;
             } else {
                 range_idx = cur_range.next_sibling_idx;
+            }
+        }
         modules[module_idx].phase = ModuleCompilationPhase::DefinitionsParsed;
         Ok(())
+    }
     fn visit_range(
         &mut self, modules: &[Module], module_idx: usize, ctx: &mut PassCtx, range_idx: usize
     ) -> Result<(), ParseError> {
         let module = &modules[module_idx];
         let cur_range = &module.tokens.ranges[range_idx];
         debug_assert!(cur_range.range_kind == TokenRangeKind::Definition || cur_range.range_kind == TokenRangeKind::Code);
         // Detect which definition we're parsing
         let mut iter = module.tokens.iter_range(cur_range);
         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_PRIMITIVE) | Some(KW_COMPOSITE) => 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(); // TODO: @Cleanup, this is really ugly. But rust...
                 let start_pos = iter.last_valid_pos();
                 let parser_type = consume_parser_type(
                     source, iter, &ctx.symbols, &ctx.heap, poly_vars, module_scope,
                     definition_id, false, 0
                 )?;
                 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(); // TODO: @Cleanup, this is really ugly. But rust...
                         consume_parser_type(
                             source, iter, &ctx.symbols, &ctx.heap, poly_vars,
                             module_scope, definition_id, false, 0
+                        )
                     },
                     &mut types_section, "an embedded type", Some(&mut close_pos)
                 )?;
                 let value = if has_embedded {
                     UnionVariantValue::Embedded(types_section.into_vec())
                 } else {
                     types_section.forget();
                     UnionVariantValue::None
                 };
                 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;
         consume_polymorphic_vars_spilled(&module.source, iter, ctx)?;
         // Parse function's argument list
         let mut parameter_section = self.variables.start_section();
         consume_parameter_list(
             &module.source, iter, ctx, &mut parameter_section, module_scope, definition_id
         )?;
         let parameters = parameter_section.into_vec();
         // Consume return types
         consume_token(&module.source, iter, TokenKind::ArrowRight)?;
         let mut return_types = self.parser_types.start_section();
         let mut open_curly_pos = iter.last_valid_pos(); // bogus value
         consume_comma_separated_until(
             TokenKind::OpenCurly, &module.source, iter, ctx,
             |source, iter, ctx| {
                 let poly_vars = ctx.heap[definition_id].poly_vars(); // TODO: @Cleanup, this is really ugly. But rust...
                 consume_parser_type(source, iter, &ctx.symbols, &ctx.heap, poly_vars, module_scope, definition_id, false, 0)
             },
             &mut return_types, "a return type", Some(&mut open_curly_pos)
         )?;
         let return_types = return_types.into_vec();
         // TODO: @ReturnValues
         match return_types.len() {
 => return Err(ParseError::new_error_str_at_pos(&module.source, open_curly_pos, "expected a return type")),
 => {},
             _ => return Err(ParseError::new_error_str_at_pos(&module.source, open_curly_pos, "multiple return types are not (yet) allowed")),
+        }
         // Consume block
         let body = self.consume_block_statement_without_leading_curly(module, iter, ctx, open_curly_pos)?;
         // Assign everything in the preallocated AST node
         let function = ctx.heap[definition_id].as_function_mut();
         function.return_types = return_types;
         function.parameters = parameters;
         function.body = body;
         Ok(())
+    }
     fn visit_component_definition(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<(), ParseError> {
         // Consume component variant and name
         let (_variant_text, _) = consume_any_ident(&module.source, iter)?;
         debug_assert!(_variant_text == KW_PRIMITIVE || _variant_text == KW_COMPOSITE);
         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;
         consume_polymorphic_vars_spilled(&module.source, iter, ctx)?;
         // Parse component's argument list
         let mut parameter_section = self.variables.start_section();
         consume_parameter_list(
             &module.source, iter, ctx, &mut parameter_section, module_scope, definition_id
         )?;
         let parameters = parameter_section.into_vec();
         // Consume block
         let body = self.consume_block_statement(module, iter, ctx)?;
         // Assign everything in the AST node
         let component = ctx.heap[definition_id].as_component_mut();
         component.parameters = parameters;
         component.body = body;
         Ok(())
+    }
     /// Consumes a block statement. If the resulting statement is not a block
     /// (e.g. for a shorthand "if (expr) single_statement") then it will be
     /// wrapped in one
     fn consume_block_or_wrapped_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<BlockStatementId, ParseError> {
         if Some(TokenKind::OpenCurly) == iter.next() {
             // This is a block statement
             self.consume_block_statement(module, iter, ctx)
         } else {
             // Not a block statement, so wrap it in one
             let mut statements = self.statements.start_section();
             let wrap_begin_pos = iter.last_valid_pos();
             self.consume_statement(module, iter, ctx, &mut statements)?;
             let wrap_end_pos = iter.last_valid_pos();
             let statements = statements.into_vec();
             let id = ctx.heap.alloc_block_statement(|this| BlockStatement{
                 this,
                 is_implicit: true,
                 span: InputSpan::from_positions(wrap_begin_pos, wrap_end_pos), // TODO: @Span
                 statements,
                 end_block: EndBlockStatementId::new_invalid(),
                 scope_node: ScopeNode::new_invalid(),
                 first_unique_id_in_scope: -1,
                 next_unique_id_in_scope: -1,
                 relative_pos_in_parent: 0,
                 locals: Vec::new(),
                 labels: Vec::new()
             });
             let end_block = ctx.heap.alloc_end_block_statement(|this| EndBlockStatement{
                 this, start_block: id, next: StatementId::new_invalid()
             });
             let block_stmt = &mut ctx.heap[id];
             block_stmt.end_block = end_block;
             Ok(id)
+        }
+    }
     /// 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, section: &mut ScopedSection<StatementId>
     ) -> Result<(), 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)?;
             section.push(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)?;
                 section.push(id.upcast());
                 let end_if = ctx.heap.alloc_end_if_statement(|this| EndIfStatement{
                     this, start_if: id, next: StatementId::new_invalid()
                 });
                 section.push(end_if.upcast());
                 let if_stmt = &mut ctx.heap[id];
                 if_stmt.end_if = end_if;
             } else if ident == KW_STMT_WHILE {
                 let id = self.consume_while_statement(module, iter, ctx)?;
                 section.push(id.upcast());
                 let end_while = ctx.heap.alloc_end_while_statement(|this| EndWhileStatement{
                     this, start_while: id, next: StatementId::new_invalid()
                 });
                 section.push(end_while.upcast());
                 let while_stmt = &mut ctx.heap[id];
                 while_stmt.end_while = end_while;
             } else if ident == KW_STMT_BREAK {
                 let id = self.consume_break_statement(module, iter, ctx)?;
                 section.push(id.upcast());
             } else if ident == KW_STMT_CONTINUE {
                 let id = self.consume_continue_statement(module, iter, ctx)?;
                 section.push(id.upcast());
             } else if ident == KW_STMT_SYNC {
                 let id = self.consume_synchronous_statement(module, iter, ctx)?;
                 section.push(id.upcast());
                 let end_sync = ctx.heap.alloc_end_synchronous_statement(|this| EndSynchronousStatement{
                     this, start_sync: id, next: StatementId::new_invalid()
                 });
                 section.push(end_sync.upcast());
                 let sync_stmt = &mut ctx.heap[id];
                 sync_stmt.end_sync = end_sync;
             } else if ident == KW_STMT_RETURN {
                 let id = self.consume_return_statement(module, iter, ctx)?;
                 section.push(id.upcast());
             } else if ident == KW_STMT_GOTO {
                 let id = self.consume_goto_statement(module, iter, ctx)?;
                 section.push(id.upcast());
             } else if ident == KW_STMT_NEW {
                 let id = self.consume_new_statement(module, iter, ctx)?;
                 section.push(id.upcast());
             } else if ident == KW_STMT_CHANNEL {
                 let id = self.consume_channel_statement(module, iter, ctx)?;
                 section.push(id.upcast().upcast());
             } else if iter.peek() == Some(TokenKind::Colon) {
                 self.consume_labeled_statement(module, iter, ctx, section)?;
             } else {
                 // Two fallback possibilities: the first one is a memory
                 // declaration, the other one is to parse it as a regular
                 // expression. This is a bit ugly
                 if let Some((memory_stmt_id, assignment_stmt_id)) = self.maybe_consume_memory_statement(module, iter, ctx)? {
                     section.push(memory_stmt_id.upcast().upcast());
                     section.push(assignment_stmt_id.upcast());
                 } else {
                     let id = self.consume_expression_statement(module, iter, ctx)?;
                     section.push(id.upcast());
+                }
+            }
         } else {
             let id = self.consume_expression_statement(module, iter, ctx)?;
             section.push(id.upcast());
+        }
         return Ok(());
+    }
     fn consume_block_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<BlockStatementId, ParseError> {
         let open_span = consume_token(&module.source, iter, TokenKind::OpenCurly)?;
         self.consume_block_statement_without_leading_curly(module, iter, ctx, open_span.begin)
+    }
     fn consume_block_statement_without_leading_curly(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx, open_curly_pos: InputPosition
     ) -> Result<BlockStatementId, ParseError> {
         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 '}'"
                 ));
+            }
             self.consume_statement(module, iter, ctx, &mut stmt_section)?;
             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_pos;
         let id = ctx.heap.alloc_block_statement(|this| BlockStatement{
             this,
             is_implicit: false,
             span: block_span,
             statements,
             end_block: EndBlockStatementId::new_invalid(),
             scope_node: ScopeNode::new_invalid(),
             first_unique_id_in_scope: -1,
             next_unique_id_in_scope: -1,
             relative_pos_in_parent: 0,
             locals: Vec::new(),
             labels: Vec::new(),
         });
         let end_block = ctx.heap.alloc_end_block_statement(|this| EndBlockStatement{
             this, start_block: id, next: StatementId::new_invalid()
         });
         let block_stmt = &mut ctx.heap[id];
         block_stmt.end_block = end_block;
         Ok(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)?;
         let true_body = self.consume_block_or_wrapped_statement(module, iter, ctx)?;
         let false_body = if has_ident(&module.source, iter, KW_STMT_ELSE) {
             iter.consume();
             let false_body = self.consume_block_or_wrapped_statement(module, iter, ctx)?;
             Some(false_body)
         } else {
             None
         };
         Ok(ctx.heap.alloc_if_statement(|this| IfStatement{
             this,
             span: if_span,
             test,
             true_body,
             false_body,
             end_if: EndIfStatementId::new_invalid(),
         }))
+    }
     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_block_or_wrapped_statement(module, iter, ctx)?;
         Ok(ctx.heap.alloc_while_statement(|this| WhileStatement{
             this,
             span: while_span,
             test,
             body,
             end_while: EndWhileStatementId::new_invalid(),
             in_sync: SynchronousStatementId::new_invalid(),
         }))
+    }
     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: None,
         }))
+    }
     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: None
         }))
+    }
     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_block_or_wrapped_statement(module, iter, ctx)?;
         Ok(ctx.heap.alloc_synchronous_statement(|this| SynchronousStatement{
             this,
             span: synchronous_span,
             body,
             end_sync: EndSynchronousStatementId::new_invalid(),
         }))
+    }
     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, "a return 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: None
         }))
+    }
     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)?;
         // TODO: @Cleanup, should just call something like consume_component_expression-ish
         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
             if expression.method == Method::UserComponent || expression.method == Method::UserFunction {
                 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 channel_type = if Some(TokenKind::OpenAngle) == iter.next() {
+        let inner_port_type = 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.
             iter.consume();
             let definition_id = self.cur_definition;
             let poly_vars = ctx.heap[definition_id].poly_vars();
             consume_parser_type(
                 &module.source, iter, &ctx.symbols, &ctx.heap,
                 poly_vars, SymbolScope::Module(module.root_id), definition_id,
                 true, 1
             )?
         } else {
             // Assume inferred
             ParserType{ elements: vec![ParserTypeElement{
                 full_span: channel_span, // TODO: @Span fix
                 variant: ParserTypeVariant::Inferred
             }]}
         };
         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_len = inner_port_type.elements.len() + 1;
         let mut from_port_type = ParserType{ elements: Vec::with_capacity(port_type_len) };
         from_port_type.elements.push(ParserTypeElement{ full_span: channel_span, variant: ParserTypeVariant::Output });
         from_port_type.elements.extend_from_slice(&inner_port_type.elements);
         let from = ctx.heap.alloc_variable(|this| Variable{
             this,
             kind: VariableKind::Local,
             identifier: from_identifier,
-            parser_type: channel_type.clone(),
+            parser_type: from_port_type,
             relative_pos_in_block: 0,
             unique_id_in_scope: -1,
         });
         let mut to_port_type = ParserType{ elements: Vec::with_capacity(port_type_len) };
         to_port_type.elements.push(ParserTypeElement{ full_span: channel_span, variant: ParserTypeVariant::Input });
         to_port_type.elements.extend_from_slice(&inner_port_type.elements);
         let to = ctx.heap.alloc_variable(|this|Variable{
             this,
             kind: VariableKind::Local,
             identifier: to_identifier,
-            parser_type: channel_type,
+            parser_type: to_port_type,
             relative_pos_in_block: 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_block: 0,
             next: StatementId::new_invalid(),
         }))
+    }
     fn consume_labeled_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx, section: &mut ScopedSection<StatementId>
     ) -> Result<(), ParseError> {
         let label = consume_ident_interned(&module.source, iter, ctx)?;
         consume_token(&module.source, iter, TokenKind::Colon)?;
         // Not pretty: consume_statement may produce more than one statement.
         // The values in the section need to be in the correct order if some
         // kind of outer block is consumed, so we take another section, push
         // the expressions in that one, and then allocate the labeled statement.
         let mut inner_section = self.statements.start_section();
         self.consume_statement(module, iter, ctx, &mut inner_section)?;
         debug_assert!(inner_section.len() >= 1);
         let stmt_id = ctx.heap.alloc_labeled_statement(|this| LabeledStatement {
             this,
             label,
             body: inner_section[0],
             relative_pos_in_block: 0,
             in_sync: SynchronousStatementId::new_invalid(),
         });
         if inner_section.len() == 1 {
             // Produce the labeled statement pointing to the first statement.
             // This is by far the most common case.
             inner_section.forget();
             section.push(stmt_id.upcast());
         } else {
             // Produce the labeled statement using the first statement, and push
             // the remaining ones at the end.
             let inner_statements = inner_section.into_vec();
             section.push(stmt_id.upcast());
             for idx in 1..inner_statements.len() {
                 section.push(inner_statements[idx])
+            }
+        }
         Ok(())
+    }
     fn maybe_consume_memory_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<Option<(MemoryStatementId, ExpressionStatementId)>, 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 = consume_parser_type(
             &module.source, iter, &ctx.symbols, &ctx.heap, poly_vars,
             SymbolScope::Definition(definition_id), definition_id, true, 0
         );
         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.elements[0].full_span.begin, identifier.span.end);
                 let assign_span = consume_token(&module.source, iter, TokenKind::Equal)?;
                 let initial_expr_begin_pos = iter.last_valid_pos();
                 let initial_expr_id = self.consume_expression(module, iter, ctx)?;
                 let initial_expr_end_pos = iter.last_valid_pos();
                 consume_token(&module.source, iter, TokenKind::SemiColon)?;
                 // Allocate the memory statement with the variable
                 let local_id = ctx.heap.alloc_variable(|this| Variable{
                     this,
                     kind: VariableKind::Local,
                     identifier: identifier.clone(),
                     parser_type,
                     relative_pos_in_block: 0,
                     unique_id_in_scope: -1,
                 });
                 let memory_stmt_id = ctx.heap.alloc_memory_statement(|this| MemoryStatement{
                     this,
                     span: memory_span,
                     variable: local_id,
                     next: StatementId::new_invalid()
                 });
                 // Allocate the initial assignment
                 let variable_expr_id = ctx.heap.alloc_variable_expression(|this| VariableExpression{
                     this,
                     identifier,
                     declaration: None,
                     used_as_binding_target: false,
                     parent: ExpressionParent::None,
                     unique_id_in_definition: -1,
                 });
                 let assignment_expr_id = ctx.heap.alloc_assignment_expression(|this| AssignmentExpression{
                     this,
                     span: assign_span,
                     left: variable_expr_id.upcast(),
                     operation: AssignmentOperator::Set,
                     right: initial_expr_id,
                     parent: ExpressionParent::None,
                     unique_id_in_definition: -1,
                 });
                 let assignment_stmt_id = ctx.heap.alloc_expression_statement(|this| ExpressionStatement{
                     this,
                     span: InputSpan::from_positions(initial_expr_begin_pos, initial_expr_end_pos),
                     expression: assignment_expr_id.upcast(),
                     next: StatementId::new_invalid(),
                 });
                 return Ok(Some((memory_stmt_id, assignment_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::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 span = iter.next_span();
             iter.consume();
             let left = expr;
             let right = self.consume_expression(module, iter, ctx)?;
             Ok(ctx.heap.alloc_assignment_expression(|this| AssignmentExpression{
                 this, span, left, operation, right,
                 parent: ExpressionParent::None,
                 unique_id_in_definition: -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 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)?;
             Ok(ctx.heap.alloc_conditional_expression(|this| ConditionalExpression{
                 this, span, test, true_expression, false_expression,
                 parent: ExpressionParent::None,
                 unique_id_in_definition: -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::PlusPlus) => Some(UO::PreIncrement),
                 Some(TK::MinusMinus) => Some(UO::PreDecrement),
                 Some(TK::Tilde) => Some(UO::BitwiseNot),
                 Some(TK::Exclamation) => Some(UO::LogicalNot),
                 _ => None
+            }
+        }
         if let Some(operation) = parse_prefix_token(iter.next()) {
             let span = iter.next_span();
             iter.consume();
             let expression = self.consume_prefix_expression(module, iter, ctx)?;
             Ok(ctx.heap.alloc_unary_expression(|this| UnaryExpression {
                 this, span, operation, expression,
                 parent: ExpressionParent::None,
                 unique_id_in_definition: -1,
             }).upcast())
         } 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 span = iter.next_span();
             iter.consume();
             if token == TokenKind::PlusPlus {
                 result = ctx.heap.alloc_unary_expression(|this| UnaryExpression{
                     this, span,
                     operation: UnaryOperator::PostIncrement,
                     expression: result,
                     parent: ExpressionParent::None,
                     unique_id_in_definition: -1,
                 }).upcast();
             } else if token == TokenKind::MinusMinus {
                 result = ctx.heap.alloc_unary_expression(|this| UnaryExpression{
                     this, span,
                     operation: UnaryOperator::PostDecrement,
                     expression: result,
                     parent: ExpressionParent::None,
                     unique_id_in_definition: -1,
                 }).upcast();
             } 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)?;
                     span.end = end_span.end;
                     result = ctx.heap.alloc_slicing_expression(|this| SlicingExpression{
                         this, span, subject, from_index, to_index,
                         parent: ExpressionParent::None,
                         unique_id_in_definition: -1,
                     }).upcast();
                 } else if Some(TokenKind::CloseSquare) == next {
                     let end_span = consume_token(&module.source, iter, TokenKind::CloseSquare)?;
                     span.end = end_span.end;
                     result = ctx.heap.alloc_indexing_expression(|this| IndexingExpression{
                         this, span, subject,
                         index: from_index,
                         parent: ExpressionParent::None,
                         unique_id_in_definition: -1,
                     }).upcast();
                 } else {
                     return Err(ParseError::new_error_str_at_pos(
                         &module.source, iter.last_valid_pos(), "unexpected token: expected ']' or '..'"
                     ));
+                }
             } else {
                 debug_assert_eq!(token, TokenKind::Dot);
                 let subject = result;
                 let field_name = consume_ident_interned(&module.source, iter, ctx)?;
                 result = ctx.heap.alloc_select_expression(|this| SelectExpression{
                     this, span, subject, field_name,
                     parent: ExpressionParent::None,
                     unique_id_in_definition: -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) {
             // Expression between parentheses
             iter.consume();
             let result = self.consume_expression(module, iter, ctx)?;
             consume_token(&module.source, iter, TokenKind::CloseParen)?;
             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,
                 unique_id_in_definition: -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,
                 unique_id_in_definition: -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,
                 unique_id_in_definition: -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,
                 unique_id_in_definition: -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 = consume_parser_type(
                     &module.source, iter, &ctx.symbols, &ctx.heap, poly_vars, symbol_scope,
                     self.cur_definition, true, 0
                 )?;
                 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,
                                     unique_id_in_definition: -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,
                                     unique_id_in_definition: -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,
                                     unique_id_in_definition: -1,
                                 }).upcast()
                             },
                             Definition::Component(_) => {
                                 // Component instantiation
                                 let arguments = self.consume_expression_list(module, iter, ctx, None)?;
                                 ctx.heap.alloc_call_expression(|this| CallExpression{
                                     this,
                                     span: parser_type.elements[0].full_span, // TODO: @Span fix
                                     parser_type,
                                     method: Method::UserComponent,
                                     arguments,
                                     definition: target_definition_id,
                                     parent: ExpressionParent::None,
                                     unique_id_in_definition: -1,
                                 }).upcast()
                             },
                             Definition::Function(function_definition) => {
                                 // Check whether it is a builtin function
                                 let method = if function_definition.builtin {
                                     match function_definition.identifier.value.as_str() {
                                         "get" => Method::Get,
                                         "put" => Method::Put,
                                         "fires" => Method::Fires,
                                         "create" => Method::Create,
                                         "length" => Method::Length,
                                         "assert" => Method::Assert,
                                         _ => unreachable!(),
+                                    }
                                 } else {
                                     Method::UserFunction
                                 };
                                 // Function call: consume the arguments
                                 let arguments = self.consume_expression_list(module, iter, ctx, None)?;
                                 ctx.heap.alloc_call_expression(|this| CallExpression{
                                     this,
                                     span: parser_type.elements[0].full_span, // TODO: @Span fix
                                     parser_type,
                                     method,
                                     arguments,
                                     definition: target_definition_id,
                                     parent: ExpressionParent::None,
                                     unique_id_in_definition: -1,
                                 }).upcast()
+                            }
+                        }
                     },
                     _ => {
                         return Err(ParseError::new_error_str_at_span(
                             &module.source, parser_type.elements[0].full_span,
                             "unexpected type in expression, note that casting expressions are not yet implemented"
                         ))
+                    }
+                }
             } 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,
                         unique_id_in_definition: -1,
                     }).upcast()
                 } else if ident_text == KW_LET {
                     // Binding expression
                     let keyword_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)?;
                     ctx.heap.alloc_binding_expression(|this| BindingExpression{
                         this,
                         span: keyword_span,
                         bound_to,
                         bound_from,
                         parent: ExpressionParent::None,
                         unique_id_in_definition: -1,
                     }).upcast()
                 } else if ident_text == KW_CAST {
                     // Casting expression
                     iter.consume();
                     let to_type = if Some(TokenKind::OpenAngle) == iter.next() {
                         iter.consume();
                         let definition_id = self.cur_definition;
                         let poly_vars = ctx.heap[definition_id].poly_vars();
                         consume_parser_type(
                             &module.source, iter, &ctx.symbols, &ctx.heap,
                             poly_vars, SymbolScope::Module(module.root_id), definition_id,
                             true, 1
                         )?
                     } else {
                         // Automatic casting with inferred target type
                         ParserType{ elements: vec![ParserTypeElement{
                             full_span: ident_span, // TODO: @Span fix
                             variant: ParserTypeVariant::Inferred,
                         }]}
                     };
                     consume_token(&module.source, iter, TokenKind::OpenParen)?;
                     let subject = self.consume_expression(module, iter, ctx)?;
                     consume_token(&module.source, iter, TokenKind::CloseParen)?;
                     ctx.heap.alloc_cast_expression(|this| CastExpression{
                         this,
                         span: ident_span,
                         to_type,
                         subject,
                         parent: ExpressionParent::None,
                         unique_id_in_definition: -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 or a 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,
                         unique_id_in_definition: -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 span = iter.next_span();
             iter.consume();
             let left = result;
             let right = higher_precedence_fn(self, module, iter, ctx)?;
             result = ctx.heap.alloc_binary_expression(|this| BinaryExpression{
                 this, span, left, operation, right,
                 parent: ExpressionParent::None,
                 unique_id_in_definition: -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 a type. A type always starts with an identifier which may indicate
 /// a builtin type or a user-defined type. The fact that it may contain
 /// polymorphic arguments makes it a tree-like structure. Because we cannot rely
 /// on knowing the exact number of polymorphic arguments we do not check for
 /// these.
 ///
 /// Note that the first depth index is used as a hack.
 // TODO: @Optimize, @Span fix, @Cleanup
 fn consume_parser_type(
     source: &InputSource, iter: &mut TokenIter, symbols: &SymbolTable, heap: &Heap, poly_vars: &[Identifier],
     cur_scope: SymbolScope, wrapping_definition: DefinitionId, allow_inference: bool, first_angle_depth: i32,
 ) -> Result<ParserType, ParseError> {
     struct Entry{
         element: ParserTypeElement,
         depth: i32,
+    }
     // After parsing the array modified "[]", we need to insert an array type
     // before the most recently parsed type.
     fn insert_array_before(elements: &mut Vec<Entry>, depth: i32, span: InputSpan) {
         let index = elements.iter().rposition(|e| e.depth == depth).unwrap();
         elements.insert(index, Entry{
             element: ParserTypeElement{ full_span: span, variant: ParserTypeVariant::Array },
             depth,
         });
+    }
     // Most common case we just have one type, perhaps with some array
     // annotations. This is both the hot-path, and simplifies the state machine
     // that follows and is responsible for parsing more complicated types.
     let element = consume_parser_type_ident(source, iter, symbols, heap, poly_vars, cur_scope, wrapping_definition, allow_inference)?;
     if iter.next() != Some(TokenKind::OpenAngle) {
         let num_embedded = element.variant.num_embedded();
         let mut num_array = 0;
         while iter.next() == Some(TokenKind::OpenSquare) {
             iter.consume();
             consume_token(source, iter, TokenKind::CloseSquare)?;
             num_array += 1;
+        }
         let array_span = element.full_span;
         let mut elements = Vec::with_capacity(num_array + num_embedded + 1);
         for _ in 0..num_array {
             elements.push(ParserTypeElement{ full_span: array_span, variant: ParserTypeVariant::Array });
+        }
         elements.push(element);
         if num_embedded != 0 {
             if !allow_inference {
                 return Err(ParseError::new_error_str_at_span(source, array_span, "type inference is not allowed here"));
+            }
             for _ in 0..num_embedded {
                 elements.push(ParserTypeElement { full_span: array_span, variant: ParserTypeVariant::Inferred });
+            }
+        }
         for _ in 0..first_angle_depth {
             consume_token(source, iter, TokenKind::CloseAngle)?;
+        }
         return Ok(ParserType{ elements });
     };
     // We have a polymorphic specification. So we start by pushing the item onto
     // our stack, then start adding entries together with the angle-brace depth
     // at which they're found.
     let mut elements = Vec::new();
     elements.push(Entry{ element, depth: 0 });
     // Start out with the first '<' consumed.
     iter.consume();
     enum State { Ident, Open, Close, Comma }
     let mut state = State::Open;
     let mut angle_depth = first_angle_depth + 1;
     loop {
         let next = iter.next();
         match state {
             State::Ident => {
                 // Just parsed an identifier, may expect comma, angled braces,
                 // or the tokens indicating an array
                 if Some(TokenKind::OpenAngle) == next {
                     angle_depth += 1;
                     state = State::Open;
                 } else if Some(TokenKind::CloseAngle) == next {
                     angle_depth -= 1;
                     state = State::Close;
                 } else if Some(TokenKind::ShiftRight) == next {
                     angle_depth -= 2;
                     state = State::Close;
                 } else if Some(TokenKind::Comma) == next {
                     state = State::Comma;
                 } else if Some(TokenKind::OpenSquare) == next {
                     let (start_pos, _) = iter.next_positions();
                     iter.consume(); // consume opening square
                     if iter.next() != Some(TokenKind::CloseSquare) {
                         return Err(ParseError::new_error_str_at_pos(
                             source, iter.last_valid_pos(),
                             "unexpected token: expected ']'"
                         ));
+                    }
                     let (_, end_pos) = iter.next_positions();
                     let array_span = InputSpan::from_positions(start_pos, end_pos);
                     insert_array_before(&mut elements, angle_depth, array_span);
                 } else {
                     return Err(ParseError::new_error_str_at_pos(
                         source, iter.last_valid_pos(),
                         "unexpected token: expected '<', '>', ',' or '['")
                     );
+                }
                 iter.consume();
             },
             State::Open => {
                 // Just parsed an opening angle bracket, expecting an identifier
                 let element = consume_parser_type_ident(source, iter, symbols, heap, poly_vars, cur_scope, wrapping_definition, allow_inference)?;
                 elements.push(Entry{ element, depth: angle_depth });
                 state = State::Ident;
             },
             State::Close => {
                 // Just parsed 1 or 2 closing angle brackets, expecting comma,
                 // more closing brackets or the tokens indicating an array
                 if Some(TokenKind::Comma) == next {
                     state = State::Comma;
                 } else if Some(TokenKind::CloseAngle) == next {
                     angle_depth -= 1;
                     state = State::Close;
                 } else if Some(TokenKind::ShiftRight) == next {
                     angle_depth -= 2;
                     state = State::Close;
                 } else if Some(TokenKind::OpenSquare) == next {
                     let (start_pos, _) = iter.next_positions();
                     iter.consume();
                     if iter.next() != Some(TokenKind::CloseSquare) {
                         return Err(ParseError::new_error_str_at_pos(
                             source, iter.last_valid_pos(),
                             "unexpected token: expected ']'"
                         ));
+                    }
                     let (_, end_pos) = iter.next_positions();
                     let array_span = InputSpan::from_positions(start_pos, end_pos);
                     insert_array_before(&mut elements, angle_depth, array_span);
                 } else {
                     return Err(ParseError::new_error_str_at_pos(
                         source, iter.last_valid_pos(),
                         "unexpected token: expected ',', '>', or '['")
                     );
+                }
                 iter.consume();
             },
             State::Comma => {
                 // Just parsed a comma, expecting an identifier or more closing
                 // braces
                 if Some(TokenKind::Ident) == next {
                     let element = consume_parser_type_ident(source, iter, symbols, heap, poly_vars, cur_scope, wrapping_definition, allow_inference)?;
                     elements.push(Entry{ element, depth: angle_depth });
                     state = State::Ident;
                 } else if Some(TokenKind::CloseAngle) == next {
                     iter.consume();
                     angle_depth -= 1;
                     state = State::Close;
                 } else if Some(TokenKind::ShiftRight) == next {
                     iter.consume();
                     angle_depth -= 2;
                     state = State::Close;
                 } else {
                     return Err(ParseError::new_error_str_at_pos(
                         source, iter.last_valid_pos(),
                         "unexpected token: expected '>' or a type name"
                     ));
+                }
+            }
+        }
         if angle_depth < 0 {
             return Err(ParseError::new_error_str_at_pos(source, iter.last_valid_pos(), "unmatched '>'"));
         } else if angle_depth == 0 {
             break;
+        }
+    }
     // If here then we found the correct number of angle braces. But we still
     // need to make sure that each encountered type has the correct number of
     // embedded types.
     let mut idx = 0;
     while idx < elements.len() {
         let cur_element = &elements[idx];
         let expected_subtypes = cur_element.element.variant.num_embedded();
         let mut encountered_subtypes = 0;
         for peek_idx in idx + 1..elements.len() {
             let peek_element = &elements[peek_idx];
             if peek_element.depth == cur_element.depth + 1 {
                 encountered_subtypes += 1;
             } else if peek_element.depth <= cur_element.depth {
                 break;
+            }
+        }
         if expected_subtypes != encountered_subtypes {
             if encountered_subtypes == 0 {
                 // Case where we have elided the embedded types, all of them
                 // should be inferred.
                 if !allow_inference {
                     return Err(ParseError::new_error_str_at_span(
                         source, cur_element.element.full_span,
                         "type inference is not allowed here"
                     ));
+                }
                 // Insert the missing types
                 let inserted_span = cur_element.element.full_span;
                 let inserted_depth = cur_element.depth + 1;
                 elements.reserve(expected_subtypes);
                 for _ in 0..expected_subtypes {
                     elements.insert(idx + 1, Entry{
                         element: ParserTypeElement{ full_span: inserted_span, variant: ParserTypeVariant::Inferred },
                         depth: inserted_depth,
                     });
+                }
             } else {
                 // Mismatch in number of embedded types, produce a neat error
                 // message.
                 let type_name = String::from_utf8_lossy(source.section_at_span(cur_element.element.full_span));
                 fn polymorphic_name_text(num: usize) -> &'static str {
                     if num == 1 { "polymorphic argument" } else { "polymorphic arguments" }
+                }
                 fn were_or_was(num: usize) -> &'static str {
                     if num == 1 { "was" } else { "were" }
+                }
                 if expected_subtypes == 0 {
                     return Err(ParseError::new_error_at_span(
                         source, cur_element.element.full_span,
                         format!(
                             "the type '{}' is not polymorphic, yet {} {} {} provided",
                             type_name, encountered_subtypes, polymorphic_name_text(encountered_subtypes),
                             were_or_was(encountered_subtypes)
+                        )
                     ));
+                }
                 let maybe_infer_text = if allow_inference {
                     " (or none, to perform implicit type inference)"
                 } else {
                     ""
                 };
                 return Err(ParseError::new_error_at_span(
                     source, cur_element.element.full_span,
                     format!(
                         "expected {} {}{} for the type '{}', but {} {} provided",
                         expected_subtypes, polymorphic_name_text(expected_subtypes),
                         maybe_infer_text, type_name, encountered_subtypes,
                         were_or_was(encountered_subtypes)
+                    )
                 ));
+            }
+        }
         idx += 1;
+    }
     let mut constructed_elements = Vec::with_capacity(elements.len());
     for element in elements.into_iter() {
         constructed_elements.push(element.element);
+    }
     Ok(ParserType{ elements: constructed_elements })
+}
 /// Consumes an identifier for which we assume that it resolves to some kind of
 /// type. Once we actually arrive at a type we will stop parsing. Hence there
 /// may be trailing '::' tokens in the iterator.
 fn consume_parser_type_ident(
     source: &InputSource, iter: &mut TokenIter, symbols: &SymbolTable, heap: &Heap, poly_vars: &[Identifier],
     mut scope: SymbolScope, wrapping_definition: DefinitionId, allow_inference: bool,
 ) -> Result<ParserTypeElement, ParseError> {
     use ParserTypeVariant as PTV;
     let (mut type_text, mut type_span) = consume_any_ident(source, iter)?;
     let variant = match type_text {
         KW_TYPE_MESSAGE => PTV::Message,
         KW_TYPE_BOOL => PTV::Bool,
         KW_TYPE_UINT8 => PTV::UInt8,
         KW_TYPE_UINT16 => PTV::UInt16,
         KW_TYPE_UINT32 => PTV::UInt32,
         KW_TYPE_UINT64 => PTV::UInt64,
         KW_TYPE_SINT8 => PTV::SInt8,
         KW_TYPE_SINT16 => PTV::SInt16,
         KW_TYPE_SINT32 => PTV::SInt32,
         KW_TYPE_SINT64 => PTV::SInt64,
         KW_TYPE_IN_PORT => PTV::Input,
         KW_TYPE_OUT_PORT => PTV::Output,
         KW_TYPE_CHAR => PTV::Character,
         KW_TYPE_STRING => PTV::String,
         KW_TYPE_INFERRED => {
             if !allow_inference {
                 return Err(ParseError::new_error_str_at_span(source, type_span, "type inference is not allowed here"));
+            }
             PTV::Inferred
         },
         _ => {
             // Must be some kind of symbolic type
             let mut type_kind = None;
             for (poly_idx, poly_var) in poly_vars.iter().enumerate() {
                 if poly_var.value.as_bytes() == type_text {
                     type_kind = Some(PTV::PolymorphicArgument(wrapping_definition, poly_idx as u32));
+                }
+            }
             if type_kind.is_none() {
                 // Check symbol table for definition. To be fair, the language
                 // only allows a single namespace for now. That said:
                 let last_symbol = symbols.get_symbol_by_name(scope, type_text);
                 if last_symbol.is_none() {
                     return Err(ParseError::new_error_str_at_span(source, type_span, "unknown type"));
+                }
                 let mut last_symbol = last_symbol.unwrap();
                 loop {
                     match &last_symbol.variant {
                         SymbolVariant::Module(symbol_module) => {
                             // Expecting more identifiers
                             if Some(TokenKind::ColonColon) != iter.next() {
                                 return Err(ParseError::new_error_str_at_span(source, type_span, "expected a type but got a module"));
+                            }
                             consume_token(source, iter, TokenKind::ColonColon)?;
                             // Consume next part of type and prepare for next
                             // lookup loop
                             let (next_text, next_span) = consume_any_ident(source, iter)?;
                             let old_text = type_text;
                             type_text = next_text;
                             type_span.end = next_span.end;
                             scope = SymbolScope::Module(symbol_module.root_id);
                             let new_symbol = symbols.get_symbol_by_name_defined_in_scope(scope, type_text);
                             if new_symbol.is_none() {
                                 // If the type is imported in the module then notify the programmer
                                 // that imports do not leak outside of a module
                                 let type_name = String::from_utf8_lossy(type_text);
                                 let module_name = String::from_utf8_lossy(old_text);
                                 let suffix = if symbols.get_symbol_by_name(scope, type_text).is_some() {
                                     format!(
                                         ". The module '{}' does import '{}', but these imports are not visible to other modules",
                                         &module_name, &type_name
+                                    )
                                 } else {
                                     String::new()
                                 };
                                 return Err(ParseError::new_error_at_span(
                                     source, next_span,
                                     format!("unknown type '{}' in module '{}'{}", type_name, module_name, suffix)
                                 ));
+                            }
                             last_symbol = new_symbol.unwrap();
                         },
                         SymbolVariant::Definition(symbol_definition) => {
                             let num_poly_vars = heap[symbol_definition.definition_id].poly_vars().len();
                             type_kind = Some(PTV::Definition(symbol_definition.definition_id, num_poly_vars as u32));
                             break;
+                        }
+                    }
+                }
+            }
             debug_assert!(type_kind.is_some());
             type_kind.unwrap()
         },
     };
     Ok(ParserTypeElement{ full_span: type_span, variant })
+}
 /// 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(
     source: &InputSource, iter: &mut TokenIter, ctx: &mut PassCtx,
     target: &mut ScopedSection<VariableId>, scope: SymbolScope, definition_id: DefinitionId
 ) -> Result<(), ParseError> {
     consume_comma_separated(
         TokenKind::OpenParen, TokenKind::CloseParen, source, iter, ctx,
         |source, iter, ctx| {
             let poly_vars = ctx.heap[definition_id].poly_vars(); // TODO: @Cleanup, this is really ugly. But rust...
             let parser_type = consume_parser_type(
                 source, iter, &ctx.symbols, &ctx.heap, poly_vars, scope,
                 definition_id, false, 0
             )?;
             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_block: 0,
                 unique_id_in_scope: -1,
             });
             Ok(parameter_id)
         },
         target, "a parameter", "a parameter list", None
+    )
+}
@@ \ No newline at end of file @@

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