Make structs work in default arguments

src/compiler.pr

@@ -4528,7 +4528,11 @@ export def walk_expression(node: &parser::Node, state: &State) -> Value {
     var expr = NO_VALUE
     if not node { return NO_VALUE }
     let scpe = state.scope
-    state.scope = node.scope
+
+    if node.scope {
+        state.scope = node.scope
+    }
+
     switch node.kind !int {
         case parser::NodeKind::NULL:
             expr = walk_Null(node, state)

src/consteval.pr

@@ -201,6 +201,11 @@ def walk_From(node: &parser::Node, state: &typechecking::State) {
 export def evaluate_parameter(node: &parser::Node, param: &parser::Node, tpe: &typechecking::Type, state: &typechecking::State) -> &compiler::Value {
     var value: &compiler::Value = null
     if param.value.param.value {
+        // Set up temporary scope
+        let prev_scope = compiler_state.module.scope
+        let temp_scope = scope::enter_scope(state.module.scope)
+
+        compiler_state.scope = temp_scope
         let previous_block = compiler_state.current_block
         let function = set_current_function()
         typechecking::walk(node, param.value.param.value, state)
@@ -209,6 +214,8 @@ export def evaluate_parameter(node: &parser::Node, param: &parser::Node, tpe: &t
         let gvalue = compiler::make_global_value(result.tpe, "default_param", null, compiler_state)
         let estate = eval::eval(compiler_state)
         result = eval::get_value(result, estate)
+
+        compiler_state.scope = prev_scope
 
         if result.kind != compiler::ValueKind::NULL {
             eval::set_value(gvalue, result, estate)

src/typechecking.pr

@@ -96,6 +96,9 @@ export type StructuralTypeMember = struct {
     return_t: &Vector(&Type)
 }
 
+// TODO Really, types should not be copied. There should only be one instance for every given type.
+// This would make comparing them so much easier but changing that at this point might be too much work.
+// It would also make the whole TypeMeta thing useless in the process.
 export type Type = struct {
     kind: TypeKind
     // Source line