Support Generic arguments to Structs

This removes StructFieldType from the TyTy base as it is not a type that
can be unified against.

It adds in a substition mapper implementation which will likely change
over time when this this support is extended over to Functions and
TupleStructs.

Note generic argument binding is not supported as part of this yet.

Fixes #235

1 files changed, 16 insertions, 25 deletions

diff --git a/gcc/rust/resolve/rust-ast-resolve-expr.h b/gcc/rust/resolve/rust-ast-resolve-expr.h
index b8cf4de..216ab41 100644
--- a/gcc/rust/resolve/rust-ast-resolve-expr.h
+++ b/gcc/rust/resolve/rust-ast-resolve-expr.h
@@ -27,6 +27,21 @@
 namespace Rust {
 namespace Resolver {
 
+class ResolvePath : public ResolverBase
+{
+public:
+  static void go (AST::PathInExpression *expr, NodeId parent)
+  {
+    ResolvePath resolver (parent);
+    resolver.resolve_path (expr);
+  }
+
+private:
+  ResolvePath (NodeId parent) : ResolverBase (parent) {}
+
+  void resolve_path (AST::PathInExpression *expr);
+};
+
 class ResolveExpr : public ResolverBase
 {
 public:
@@ -50,31 +65,7 @@ public:
       ResolveExpr::go (elem.get (), expr.get_node_id ());
   }
 
-  void visit (AST::PathInExpression &expr)
-  {
-    // name scope first
-    if (resolver->get_name_scope ().lookup (expr.as_string (), &resolved_node))
-      {
-	resolver->insert_resolved_name (expr.get_node_id (), resolved_node);
-	resolver->insert_new_definition (expr.get_node_id (),
-					 Definition{expr.get_node_id (),
-						    parent});
-      }
-    // check the type scope
-    else if (resolver->get_type_scope ().lookup (expr.as_string (),
-						 &resolved_node))
-      {
-	resolver->insert_resolved_type (expr.get_node_id (), resolved_node);
-	resolver->insert_new_definition (expr.get_node_id (),
-					 Definition{expr.get_node_id (),
-						    parent});
-      }
-    else
-      {
-	rust_error_at (expr.get_locus (), "unknown path %s",
-		       expr.as_string ().c_str ());
-      }
-  }
+  void visit (AST::PathInExpression &expr) { ResolvePath::go (&expr, parent); }
 
   void visit (AST::ReturnExpr &expr)
   {