Kit.Core/LibExternal/System.Reactive/Linq/Observable/Defer.cs

51 lines
1.5 KiB
C#

// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT License.
// See the LICENSE file in the project root for more information.
namespace System.Reactive.Linq.ObservableImpl
{
internal sealed class Defer<TValue> : Producer<TValue, Defer<TValue>._>, IEvaluatableObservable<TValue>
{
private readonly Func<IObservable<TValue>> _observableFactory;
public Defer(Func<IObservable<TValue>> observableFactory)
{
_observableFactory = observableFactory;
}
protected override _ CreateSink(IObserver<TValue> observer) => new(_observableFactory, observer);
protected override void Run(_ sink) => sink.Run();
public IObservable<TValue> Eval() => _observableFactory();
internal sealed class _ : IdentitySink<TValue>
{
private readonly Func<IObservable<TValue>> _observableFactory;
public _(Func<IObservable<TValue>> observableFactory, IObserver<TValue> observer)
: base(observer)
{
_observableFactory = observableFactory;
}
public void Run()
{
IObservable<TValue> result;
try
{
result = _observableFactory();
}
catch (Exception exception)
{
ForwardOnError(exception);
return;
}
Run(result);
}
}
}
}