"Implement" #resource tag and various restrictions on library definitions.

dart/frog/leg/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('../tree/tree.dart');
 #import('../scanner/scannerlib.dart');
 #import('../leg.dart');  // TODO(karlklose): we only need type.
 #import('../util/util.dart');
@@ skipping 295 matching lines @@
 
   void forEachExport(f(Element element)) {
     elements.forEach((SourceString _, Element e) {
       if (this === e.getLibrary()
           && e.kind !== ElementKind.PREFIX
           && e.kind !== ElementKind.FOREIGN) {
         if (!e.name.isPrivate()) f(e);
       }
     });
   }
+
+  bool hasLibraryName() => (!tags.isEmpty()) && tags.reverse().head.isLibrary();

[ngeoffray, 2012/03/23 17:22:52]

The 'reverse' call looks sooooooo expensive for so little.

[ahe, 2012/03/24 08:02:03]

Especially when the library tag is recorded already in the field named
[libraryTag]. Doh!

 }
 
 class PrefixElement extends Element {
   Map<SourceString, Element> imported;
   Token firstPosition;
 
   PrefixElement(SourceString prefix, Element enclosing, this.firstPosition)
     : imported = new Map<SourceString, Element>(),
       super(prefix, ElementKind.PREFIX, enclosing);
 
@@ skipping 619 matching lines @@
   final Node node;
   Type bound;
   Type type;
   TypeVariableElement(name, Element enclosing, this.node, this.type,
                       [this.bound])
     : super(name, ElementKind.TYPE_VARIABLE, enclosing);
   Type computeType(compiler) => type;
   Node parseNode(compiler) => node;
   toString() => "${enclosingElement.toString()}.${name.slowToString()}";
 }