anchor.diff:  }
   
   @immutable
  -abstract class Selector<Input, Output> {
  +abstract class SelectorDelegate<Input, Output> {
     ProviderBase<ProviderBaseSubscription, Input> get provider;
   
     VoidCallback watchOwner(
  
positive.code:   bool shouldRebuild(Output previousValue, Output newValue);
  }
  
  class _Selector<Input, Output> implements Selector<Input, Output> {
    _Selector(this._selector, this.provider);
  
    final Output Function(Input value) _selector;
    @override
  
negative.code: import 'package:flutter_hooks/flutter_hooks.dart';
  import 'package:collection/collection.dart';
  
  export 'package:flutter_river_pod/flutter_river_pod.dart';
  
  Output useSelector<Input, Output>(SelectorDelegate<Input, Output> selector) {
    final owner = ProviderStateOwnerScope.of(useContext());
    return Hook.use(_BaseProviderSelectorHook<Input, Output>(owner, selector));
  }
  