anchor.diff:      for (var field in element.fields) {
         log.warning('Found field $field');
       }
  -    log.warning(new DescriptionGenerator(element).generatedCode);
  +    var generator = new DescriptionGenerator(element);
  +    descriptionGenerators.add(generator);
     }
   }
   
  
positive.code:     var library = resolver.getLibrary(inputId);
      log.warning(
          'Investigating library ${library.exportNamespace.definedNames.keys}');
      library.visitChildren(new DeepEqualityVisitor());
    }
  
    @override
  
negative.code: class DeepEqualityVisitor extends SimpleElementVisitor {
    static const deepEqualityKey = const _UniqueKey(
        'asset:compiled_mirrors/lib/compiled_mirrors.dart', 'CompileMirror');
    final List<DescriptionGenerator> descriptionGenerators =
        <DescriptionGenerator>[];
  
    DeepEqualityVisitor();
  
  