public IAsyncReducer <TReduction, TInput> Apply <TReduction>(IAsyncReducer <TReduction, TResult> next) => Left.Apply(Right.Apply(next));
public IAsyncReducer <TReduction, TInput> Apply <TReduction>(IAsyncReducer <TReduction, TResult> next) => Async.Apply(next);
public static IAsyncReducer <TextWriter, TInput> AsyncWriteReducer <TInput>( this IAsyncTransducer <TInput, string> transducer) => transducer.Apply(AsyncWriteReducer());