public static IAsyncObservable <TSource> Delay <TSource>(this IAsyncObservable <TSource> source, TimeSpan dueTime)
{
if (source == null)
{
throw new ArgumentNullException(nameof(source));
}
return(Create <TSource>(async observer =>
{
var(sink, drain) = await AsyncObserver.Delay(observer, dueTime).ConfigureAwait(false);
var subscription = await source.SubscribeSafeAsync(sink).ConfigureAwait(false);
return StableCompositeAsyncDisposable.Create(subscription, drain);
}));
}