anchor.diff:  }
   
   /// State for a [StoreWatcher] widget.
  -class StoreWatcherState extends State<StoreWatcher>
  -    with StoreWatcherMixin<StoreWatcher> {
  -  // If you get these errors from the analyzer, then you need to add a file
  -  // analysis_options.yaml like you find in the root of this repo.
  -  // [error] The class 'StoreWatcherMixin' cannot be used as a mixin because it
  -  // extends a class other than Object.
  -  // [error] The class 'StoreWatcherMixin' cannot be used as a mixin because it
  -  // references 'super'
  +class StoreWatcherState extends State<StoreWatcher> with StoreWatcherMixin<StoreWatcher> {
   
     final Map<StoreToken, Store> _storeTokens = <StoreToken, Store>{};
   
  
positive.code: 
    @override
    String toString() => '[${_value.runtimeType}(${_value.hashCode})]';
  }
  
negative.code:   @protected
    Store listenToStore(StoreToken token, [ValueChanged<Store> onStoreChanged]) {
      final Store store = token._value;
      _streamSubscriptions[store] = store.listen(onStoreChanged ?? _handleStoreChanged);
      return store;
    }
  
  