private bool MoveNext()
{
TSource item;
if (_enumerator == null)
{
return(false);
}
lock (_enumerator)
{
if (!_enumerator.MoveNext())
{
_enumerator.Dispose();
_cancellationTokenSource.Cancel();
_enumerator = null;
return(false);
}
item = _enumerator.Current;
}
var key = _keySelector(item);
var element = _resultSelector(item);
if (_proxies.TryGetOrAdd(key, _ => new ProxyObservable <TElement>(), out var proxy))
{
var progressor = Progressor <TElement> .CreateFromIObservable
(
proxy,
Advance,
_cancellationTokenSource.Token
);
var items = ProgressiveCollection <TElement> .Create
(
progressor,
new ThreadSafeCollection <TElement>(),
EqualityComparer <TElement> .Default
);
var result = new Grouping <TKey, TElement>(key, items);
_results.Add(result);
}
proxy.OnNext(element);
return(true);
}
