// this will be called FIRST in the use of the enumerator, so we can await the enumerator get task, the rest can use result safely
public ValueTask <bool> MoveNextAsync()
{
if (CancellationToken.IsCancellationRequested)
{
return(new ValueTask <bool>(Task.FromCanceled <bool>(CancellationToken)));
}
return(new ValueTask <bool>(GetEnumerator.ContinueWith <bool>(x => x.Result.MoveNext())));
}
public object InvokeGetEnumerator(object instance)
{
try
{
return(GetEnumerator.Invoke(instance, null) !);
}
catch (TargetInvocationException exception)
{
throw new EnumerationException($"Unhandled exception in {GetEnumerator.DeclaringType!.Name}.GetEnumerator().", exception.InnerException !);
}
}
public virtual IEnumerator <TSource> GetEnumerator <TSource>(IObservable <TSource> source)
{
#if !NO_PERF && !NO_CDS
var e = new GetEnumerator <TSource>();
return(e.Run(source));
#else
var q = new Queue <Notification <TSource> >();
var s = new Semaphore(0, int.MaxValue);
return(PushToPull(
source,
x =>
{
lock (q)
q.Enqueue(x);
s.Release();
},
() =>
{
s.WaitOne();
lock (q)
return q.Dequeue();
}));
#endif
}
// this will be called FIRST in the use of the enumerator, so we can await the enumerator get task, the rest can use result safely
public async Task <bool> MoveNext(CancellationToken cancellationToken)
{
return((await GetEnumerator.ConfigureAwait(false)).MoveNext());
}
public virtual IEnumerator <TSource> GetEnumerator <TSource>(IObservable <TSource> source)
{
var e = new GetEnumerator <TSource>();
return(e.Run(source));
}