anchor.diff:  
     String get documentation {
       var commentRefs;
  -
  -    if (_documentation != null) return _documentation;
  -
  +    if (_documentation != null) {
  +      return _documentation;
  +    }
       if (element == null) {
         return null;
       }
  -
       _documentation = element.computeDocumentationComment();
   
       if (_documentation == null && canOverride()) {
  -      if (getOverriddenElement() != null) {
  -        var melement = getOverriddenElement();
  -        _documentation = melement.documentation;
  -        if (melement.element.node is AnnotatedNode) {
  +      var overrideElement = getOverriddenElement();
  +      if (overrideElement != null) {
  +        _documentation = overrideElement.documentation;
  +        if (overrideElement.element.node is AnnotatedNode) {
             commentRefs =
  -              (melement.element.node as AnnotatedNode).documentationComment.references;
  +              (overrideElement.element.node as AnnotatedNode).documentationComment.references;
           }
         }
       } else {
  
positive.code:             (element.node as AnnotatedNode).documentationComment.references;
        }
      }
  
      if (_documentation != null) {
        _documentation = _processRefs(stripComments(_documentation), commentRefs);
      }
  
negative.code:     if (!package.isDocumented(this) || name.startsWith('_')) {
        return name;
      }
      Class c = getEnclosingElement();
      if (c != null && c.name.startsWith('_')) {
        return '${c.name}.${name}';
      }
      if (c != null) {
        return '${this.library.name}/${getFileNameFor(c.name)}#$name)}';
      } else {
        return '${this.library.name}/${getFileNameFor(name)}';
      }
  