anchor.diff:  ///             AppRoutes<T>(
   ///               preloadedState: T(),
   ///               middleware:[],
  -///               slots: {
  +///               pages: {
   ///                 'message': MsgConn() + MessageComponent(),
   ///                 'personal': PersonalConn() + PersonalComponent(),
   ///               },
  
positive.code:     List<Middleware<T>> middleware,
    })  : assert(preloadedState != null,
              'Expected the preloadedState to be non-null value.'),
          assert(pages != null, 'Expected the slots to be non-null value.'),
          _store = createPageStore<T>(
            preloadedState,
            _createReducer<T>(pages, reducer),
  
negative.code:   }
  
    static Reducer<T> _createReducer<T>(
        Map<String, Dependent<T>> pages, Reducer<T> reducer) {
      final Map<String, SubReducer<T>> subReducerMap = pages.map((String path,
              Dependent<T> dependent) =>
          MapEntry<String, SubReducer<T>>(path, dependent.createSubReducer()));
  
  