public void Subscribe(ISingleSubscriber <T> s)
{
SingleDisposable sd = new SingleDisposable(this, s);
s.OnSubscribe(sd);
if (Add(sd))
{
if (sd.IsDisposed())
{
Remove(sd);
}
if (Volatile.Read(ref once) == 0)
{
if (Interlocked.CompareExchange(ref once, 1, 0) == 0)
{
source.Subscribe(this);
}
}
}
else
{
ValueOrError r = Volatile.Read(ref result);
if (r.IsError())
{
s.OnError(r.error);
}
else
{
s.OnSuccess(r.value);
}
}
}
public static IEventReader Once(this IEventReader reader)
{
return(new AnonymousEventReader((Action reaction) =>
{
var disp = new SingleDisposable();
disp.Disposable = reader.Subscribe(() =>
{
reaction();
disp.Dispose();
});
return disp;
}));
}
// Result stream is called only once, then the connection is disposed.
public static IEventReader <T> Once <T>(this IEventReader <T> eventReader)
{
return(new AnonymousEventReader <T>((Action <T> reaction) =>
{
var disp = new SingleDisposable();
disp.Disposable = eventReader.Subscribe(val =>
{
reaction(val);
disp.Dispose();
});
return disp;
}));
}
public static IEventStream Once(this IEventStream stream)
{
return(new AnonymousEventStream((Action reaction) =>
{
var disp = new SingleDisposable();
disp.Disposable = stream.Subscribe(() =>
{
reaction();
disp.Dispose();
});
return disp;
}));
}
internal bool Remove(SingleDisposable sd)
{
return(ProcessorHelper.Remove(ref subscribers, sd, Terminated, Empty));
}
internal bool Add(SingleDisposable sd)
{
return(ProcessorHelper.Add(ref subscribers, sd, Terminated));
}
