Introduce WorldImpact

pkg/compiler/lib/src/typechecker.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 dart2js;
 
 class TypeCheckerTask extends CompilerTask {
   TypeCheckerTask(Compiler compiler) : super(compiler);
   String get name => "Type checker";
 
-  void check(TreeElements elements) {
-    AstElement element = elements.analyzedElement;
+  void check(AstElement element) {
+    if (element.isClass) return;
     if (element.isTypedef) return;
-
+    ResolvedAst resolvedAst = element.resolvedAst;
     compiler.withCurrentElement(element, () {
       measure(() {
-        Node tree = element.node;
-        TypeCheckerVisitor visitor =
-            new TypeCheckerVisitor(compiler, elements, compiler.types);
+        TypeCheckerVisitor visitor = new TypeCheckerVisitor(
+            compiler, resolvedAst.elements, compiler.types);
         if (element.isField) {
           visitor.analyzingInitializer = true;
         }
-        tree.accept(visitor);
+        resolvedAst.node.accept(visitor);
       });
     });
   }
 }
 
 /**
  * Class used to report different warnings for differrent kinds of members.
  */
 class MemberKind {
   static const MemberKind METHOD = const MemberKind("method");
@@ skipping 1829 matching lines @@
 
   visitTypedef(Typedef node) {
     // Do not typecheck [Typedef] nodes.
   }
 
   visitNode(Node node) {
     compiler.internalError(node,
         'Unexpected node ${node.getObjectDescription()} in the type checker.');
   }
 }