Implement top-level getters.

dart/sdk/lib/_internal/compiler/implementation/closure.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.
 
 library closureToClassMapper;
 
 import "elements/elements.dart";
 import "dart2jslib.dart";
 import "dart_types.dart";
 import "scanner/scannerlib.dart" show Token;
 import "tree/tree.dart";
 import "util/util.dart";
 import "elements/modelx.dart" show ElementX, FunctionElementX, ClassElementX;
 
 class ClosureNamer {
   SourceString getClosureVariableName(SourceString name, int id) {
     return new SourceString("${name.slowToString()}_$id");
   }
 }
 
-
 class ClosureTask extends CompilerTask {
   Map<Node, ClosureClassMap> closureMappingCache;
   ClosureNamer namer;
   ClosureTask(Compiler compiler, this.namer)
       : closureMappingCache = new Map<Node, ClosureClassMap>(),
         super(compiler);
 
   String get name => "Closure Simplifier";
 
   ClosureClassMap computeClosureToClassMapping(Element element,
@@ skipping 29 matching lines @@
         compiler.internalError("No closure cache", node: node);
       }
       return nestedClosureData;
     });
   }
 }
 
 // TODO(ahe): These classes continuously cause problems.  We need to
 // move these classes to elements/modelx.dart or see if we can find a
 // more general solution.
-class ClosureFieldElement extends ElementX {
+class ClosureFieldElement extends ElementX implements VariableElement {
+  /// The source variable this element refers to.
+  final Element variableElement;
+
   ClosureFieldElement(SourceString name,
                       this.variableElement,
                       ClassElement enclosing)
       : super(name, ElementKind.FIELD, enclosing);
 
+  VariableListElement get variables {
+    throw new SpannableAssertionFailure(
+        variableElement, 'Should not access variables of ClosureFieldElement.');
+  }
+
+  Expression get cachedNode {
+    throw new SpannableAssertionFailure(
+        variableElement,
+        'Should not access cachedNode of ClosureFieldElement.');
+  }
+
   bool isInstanceMember() => true;
   bool isAssignable() => false;
   // The names of closure variables don't need renaming, since their use is very
   // simple and they have 1-character names in the minified mode.
   bool hasFixedBackendName() => true;
   String fixedBackendName() => name.slowToString();
 
   DartType computeType(Compiler compiler) {
     return variableElement.computeType(compiler);
   }
 
   String toString() => "ClosureFieldElement($name)";
-
-  /**
-   * The source variable this element refers to.
-   */
-  final Element variableElement;
 }
 
 // TODO(ahe): These classes continuously cause problems.  We need to
 // move these classes to elements/modelx.dart or see if we can find a
 // more general solution.
 class ClosureClassElement extends ClassElementX {
   DartType rawType;
   DartType thisType;
   /// Node that corresponds to this closure, used for source position.
   final FunctionExpression node;
@@ skipping 713 matching lines @@
   }
 
   visitTryStatement(TryStatement node) {
     // TODO(ngeoffray): implement finer grain state.
     bool oldInTryStatement = inTryStatement;
     inTryStatement = true;
     node.visitChildren(this);
     inTryStatement = oldInTryStatement;
   }
 }