diff options
Diffstat (limited to 'Rx.NET/System.Reactive.Linq/Reactive/Linq/Observαble/LastAsync.cs')
-rw-r--r-- | Rx.NET/System.Reactive.Linq/Reactive/Linq/Observαble/LastAsync.cs | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/Rx.NET/System.Reactive.Linq/Reactive/Linq/Observαble/LastAsync.cs b/Rx.NET/System.Reactive.Linq/Reactive/Linq/Observαble/LastAsync.cs new file mode 100644 index 0000000..1ecd930 --- /dev/null +++ b/Rx.NET/System.Reactive.Linq/Reactive/Linq/Observαble/LastAsync.cs @@ -0,0 +1,140 @@ +// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information. + +#if !NO_PERF +using System; + +namespace System.Reactive.Linq.Observαble +{ + class LastAsync<TSource> : Producer<TSource> + { + private readonly IObservable<TSource> _source; + private readonly Func<TSource, bool> _predicate; + private readonly bool _throwOnEmpty; + + public LastAsync(IObservable<TSource> source, Func<TSource, bool> predicate, bool throwOnEmpty) + { + _source = source; + _predicate = predicate; + _throwOnEmpty = throwOnEmpty; + } + + protected override IDisposable Run(IObserver<TSource> observer, IDisposable cancel, Action<IDisposable> setSink) + { + if (_predicate != null) + { + var sink = new π(this, observer, cancel); + setSink(sink); + return _source.SubscribeSafe(sink); + } + else + { + var sink = new _(this, observer, cancel); + setSink(sink); + return _source.SubscribeSafe(sink); + } + } + + class _ : Sink<TSource>, IObserver<TSource> + { + private readonly LastAsync<TSource> _parent; + private TSource _value; + private bool _seenValue; + + public _(LastAsync<TSource> parent, IObserver<TSource> observer, IDisposable cancel) + : base(observer, cancel) + { + _parent = parent; + + _value = default(TSource); + _seenValue = false; + } + + public void OnNext(TSource value) + { + _value = value; + _seenValue = true; + } + + public void OnError(Exception error) + { + base._observer.OnError(error); + base.Dispose(); + } + + public void OnCompleted() + { + if (!_seenValue && _parent._throwOnEmpty) + { + base._observer.OnError(new InvalidOperationException(Strings_Linq.NO_ELEMENTS)); + } + else + { + base._observer.OnNext(_value); + base._observer.OnCompleted(); + } + + base.Dispose(); + } + } + + class π : Sink<TSource>, IObserver<TSource> + { + private readonly LastAsync<TSource> _parent; + private TSource _value; + private bool _seenValue; + + public π(LastAsync<TSource> parent, IObserver<TSource> observer, IDisposable cancel) + : base(observer, cancel) + { + _parent = parent; + + _value = default(TSource); + _seenValue = false; + } + + public void OnNext(TSource value) + { + var b = false; + + try + { + b = _parent._predicate(value); + } + catch (Exception ex) + { + base._observer.OnError(ex); + base.Dispose(); + return; + } + + if (b) + { + _value = value; + _seenValue = true; + } + } + + public void OnError(Exception error) + { + base._observer.OnError(error); + base.Dispose(); + } + + public void OnCompleted() + { + if (!_seenValue && _parent._throwOnEmpty) + { + base._observer.OnError(new InvalidOperationException(Strings_Linq.NO_MATCHING_ELEMENTS)); + } + else + { + base._observer.OnNext(_value); + base._observer.OnCompleted(); + } + + base.Dispose(); + } + } + } +} +#endif
\ No newline at end of file |