anchor.diff:    get typeVariables => emptyList;
     get typeArguments => emptyList;
     get metadata => emptyList;
  -  Map<Symbol, Mirror> get members => emptyMap;
  -  Map<Symbol, MethodMirror> get constructors => emptyMap;
   
     String toString() => "FunctionTypeMirror on '${_n(simpleName)}'";
   
  
positive.code:     return _cachedMembers;
    }
  
    Map<Symbol, MethodMirror> _cachedMethods;
    Map<Symbol, MethodMirror> get _methods {
      if (_cachedMethods == null) {
        _cachedMethods = _filterMap(
            _members,
            (key, value) => (value is MethodMirror && value.isRegularMethod));
      }
      return _cachedMethods;
    }
  
    Map<Symbol, MethodMirror> _cachedConstructors;
    Map<Symbol, MethodMirror> get _constructors {
      if (_cachedConstructors == null) {
  
negative.code:   final String _msg;
    const _InternalMirrorError(String this._msg);
    String toString() => _msg;
  }
  
  Map _makeMemberMap(List mirrors) {
  