RxFormFieldState<B extends RxBlocTypeBase, T>  typedef 
 
        RxFormFieldState<B extends RxBlocTypeBase, T> =
     Stream<T>  Function(B)
     
    
Type used as a contract for defining the RxFormFieldBuilder state
Implementation
typedef RxFormFieldState<B extends RxBlocTypeBase, T> = Stream<T> Function(B);