Support runtime check of function types.

sdk/lib/_internal/compiler/implementation/resolution/members.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of resolution;
 
 abstract class TreeElements {
   Element get currentElement;
   Set<Node> get superUses;
 
@@ skipping 1945 matching lines @@
     enclosingElement = function;
     // Run the body in a fresh statement scope.
     StatementScope oldStatementScope = statementScope;
     statementScope = new StatementScope();
     visit(node.body);
     statementScope = oldStatementScope;
 
     scope = oldScope;
     enclosingElement = previousEnclosingElement;
 
+    ClassElement thisClass = enclosingElement.getEnclosingClass();

[ngeoffray, 2013/03/13 09:30:46]

Please add a comment.

[Johnni Winther, 2013/03/22 07:30:24]

Changed to use the type of [function] itself, thus registering the function if
is uses type variables.

+    if (thisClass != null && !thisClass.typeVariables.isEmpty) {
+      world.registerGenericClosure(function, mapping);
+    }
     world.registerInstantiatedClass(compiler.functionClass, mapping);
   }
 
   visitIf(If node) {
     visit(node.condition);
     visit(node.thenPart);
     visit(node.elsePart);
   }
 
   static bool isLogicalOperator(Identifier op) {
@@ skipping 1879 matching lines @@
     return e;
   }
 
   /// Assumed to be called by [resolveRedirectingFactory].
   Element visitReturn(Return node) {
     Node expression = node.expression;
     return finishConstructorReference(visit(expression),
                                       expression, expression);
   }
 }