Evaluate compile-time constants of metadata.

dart/lib/compiler/implementation/resolver.dart

Index: dart/lib/compiler/implementation/resolver.dart
diff --git a/dart/lib/compiler/implementation/resolver.dart b/dart/lib/compiler/implementation/resolver.dart
index bcd63bb596299f64a75eed2676ce93086146c91e..1431ac57ca36c7e540765bd3491e69d8fd756903 100644
--- a/dart/lib/compiler/implementation/resolver.dart
+++ b/dart/lib/compiler/implementation/resolver.dart
@@ -399,6 +399,18 @@ class ResolverTask extends CompilerTask {
                             element);
   }
 
+  void resolveMetadataAnnotation(MetadataAnnotation annotation) {
+    Node node = annotation.parseNode(compiler);
+    Element fakeElement = new Element(const SourceString(''),

[ngeoffray, 2012/08/22 14:28:56]

Should we have a metadata element instead? This sounds like a big hack around
the system.

[ahe, 2012/08/22 17:23:02]

Done.

+                                      ElementKind.FUNCTION,
+                                      annotation.enclosingElement);

[Johnni Winther, 2012/08/22 13:45:40]

The element kind should be something else. We cannot risk code wrongfully
relying on fakeElement to be a function.

[ahe, 2012/08/22 17:23:02]

Done.

+    ResolverVisitor visitor = new ResolverVisitor(compiler, fakeElement);
+    node.accept(visitor);
+    annotation.value = compiler.constantHandler.compileNodeWithDefinitions(
+        node, visitor.mapping);
+    print(annotation);

[Johnni Winther, 2012/08/22 13:45:40]

Debug output.

[ahe, 2012/08/22 17:23:02]

Done.

+  }
+
   error(Node node, MessageKind kind, [arguments = const []]) {
     ResolutionError message = new ResolutionError(kind, arguments);
     compiler.reportError(node, message);