// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information. #if !NO_PERF using System; using System.Reactive.Disposables; namespace System.Reactive.Linq.Observαble { class Never : IObservable { public IDisposable Subscribe(IObserver observer) { if (observer == null) throw new ArgumentNullException("observer"); return Disposable.Empty; } } } #endif