Evaluate compile-time constants of metadata.

dart/lib/compiler/implementation/elements/elements.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('elements');
 
 #import('dart:uri');
 
 #import('../tree/tree.dart');
 #import('../scanner/scannerlib.dart');
 #import('../leg.dart');  // TODO(karlklose): we only need type.
 #import('../util/util.dart');
 
+const int STATE_NOT_STARTED = 0;
+const int STATE_STARTED = 1;
+const int STATE_DONE = 2;
+
 class ElementCategory {
   /**
    * Represents things that we don't expect to find when looking in a
    * scope.
    */
   static final int NONE = 0;
 
   /** Field, parameter, or variable. */
   static final int VARIABLE = 1;
 
@@ skipping 92 matching lines @@
 
   Node parseNode(DiagnosticListener listener) {
     listener.cancel("Internal Error: $this.parseNode", token: position());
   }
 
   Type computeType(Compiler compiler) {
     compiler.internalError("$this.computeType.", token: position());
   }
 
   void addMetadata(MetadataAnnotation annotation) {
+    assert(annotation.annotatedElement === null);
+    annotation.annotatedElement = this;
     metadata = metadata.prepend(annotation);
   }
 
   bool isFunction() => kind === ElementKind.FUNCTION;
   bool isConstructor() => isFactoryConstructor() || isGenerativeConstructor();
   bool isClosure() => false;
   bool isMember() {
     // Check that this element is defined in the scope of a Class.
     Element enclosing = enclosingElement;
     if (enclosing !== null &&
@@ skipping 938 matching lines @@
       TypeVariableType variableType = new TypeVariableType(variableElement);
       variableElement.type = variableType;
       arguments.addLast(variableType);
     }
     return arguments.toLink();
   }
 }
 
 class ClassElement extends ScopeContainerElement
     implements TypeDeclarationElement {
-  static final int STATE_NOT_STARTED = 0;
-  static final int STATE_STARTED = 1;
-  static final int STATE_DONE = 2;
-
   final int id;
   InterfaceType type;
   Type supertype;
   Type defaultClass;
   Link<Type> interfaces;
   SourceString nativeName;
   int supertypeLoadState;
   int resolutionState;
 
   // backendMembers are members that have been added by the backend to simplify
@@ skipping 508 matching lines @@
  * are the same compile-time constant, [: const Data() :].
  *
  * The mirror system does not have a concept matching this class.
  */
 class MetadataAnnotation {
   /**
    * The compile-time constant which this annotation resolves to.
    * In the mirror system, this would be an object mirror.
    */
   abstract Constant get value();
+  Element annotatedElement;
+  int resolutionState;
 
-  // TODO(ahe): Add more functionality as needed.
+  MetadataAnnotation([this.resolutionState = STATE_NOT_STARTED]);
+
+  abstract Node parseNode(DiagnosticListener listener);
+
+  MetadataAnnotation ensureResolved(Compiler compiler) {
+    if (resolutionState == STATE_NOT_STARTED) {
+      compiler.resolver.resolveMetadataAnnotation(this);
+    }
+    return this;
+  }
+
+  String toString() => 'MetadataAnnotation($value, $resolutionState)';
 }