anchor.diff:  ///           children: <Widget>[
   ///             Text('You have pushed the button this many times:'),
   ///             Consumer(
  -///               builder: (BuildContext context, ScopedReader watch, Widget child) {
  +///               builder: (BuildContext context, ScopedReader watch, Widget? child) {
   ///                 // This builder will only get called when the counterProvider
   ///                 // is updated.
   ///                 final count = watch(counterProvider).state;
  
positive.code: ///   Widget build(BuildContext context) {
  ///     return Scaffold(
  ///       appBar: AppBar(
  ///         title: Text(widget.title)
  ///       ),
  ///       body: Center(
  ///         child: Column(
  
negative.code: ///                   mainAxisAlignment: MainAxisAlignment.spaceEvenly,
  ///                   children: <Widget>[
  ///                     Text('$count'),
  ///                     child!,
  ///                   ],
  ///                 );
  ///               },
  