/// <summary>
/// Subscribes to a stream with a per-epoch callback applied at each worker.
/// </summary>
/// <typeparam name="R">record type</typeparam>
/// <param name="stream">input stream</param>
/// <param name="action">callback on worker id and records</param>
/// <returns>subscription for synchronization</returns>
public static Subscription Subscribe <R>(this Dataflow.Stream <R, Epoch> stream, Action <int, IEnumerable <R> > action)
{
return(stream.Subscribe((j, t, l) => action(j, l)));
}
/// <summary>
/// Subscribes to a stream with no callback.
/// </summary>
/// <typeparam name="R">record type</typeparam>
/// <param name="stream">input stream</param>
/// <returns>subscription for synchronization</returns>
public static Subscription Subscribe <R>(this Dataflow.Stream <R, Epoch> stream)
{
return(stream.Subscribe(x => { }));
}