Interface IStage<TIn, TOut>
General interface for stream transformation.
Custom IStage<TIn, TOut> implementations are intended to be used with Transform<TIn, TOut1, TOut2, TMat>(Flow<TIn, TOut1, TMat>, Func<IStage<TOut1, TOut2>>) to extend the FlowOperations API when there is no specialized operator that performs the transformation.
It is possible to keep state in the concrete IStage<TIn, TOut> instance with ordinary instance variables. The ITransformerLike<TIn, TOut> is executed by an actor and therefore you do not have to add any additional thread safety or memory visibility constructs to access the state from the callback methods.
[Obsolete("Please use GraphStage instead. [1.1.0]")] public interface IStage<in TIn, out TOut>