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

97 lines
3.2 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 static class Select<TSource, TResult>
{
internal sealed class Selector : Producer<TResult, Selector._>
{
private readonly IObservable<TSource> _source;
private readonly Func<TSource, TResult> _selector;
public Selector(IObservable<TSource> source, Func<TSource, TResult> selector)
{
_source = source;
_selector = selector;
}
protected override _ CreateSink(IObserver<TResult> observer) => new(_selector, observer);
protected override void Run(_ sink) => sink.Run(_source);
internal sealed class _ : Sink<TSource, TResult>
{
private readonly Func<TSource, TResult> _selector;
public _(Func<TSource, TResult> selector, IObserver<TResult> observer)
: base(observer)
{
_selector = selector;
}
public override void OnNext(TSource value)
{
TResult result;
try
{
result = _selector(value);
}
catch (Exception exception)
{
ForwardOnError(exception);
return;
}
ForwardOnNext(result);
}
}
}
internal sealed class SelectorIndexed : Producer<TResult, SelectorIndexed._>
{
private readonly IObservable<TSource> _source;
private readonly Func<TSource, int, TResult> _selector;
public SelectorIndexed(IObservable<TSource> source, Func<TSource, int, TResult> selector)
{
_source = source;
_selector = selector;
}
protected override _ CreateSink(IObserver<TResult> observer) => new(_selector, observer);
protected override void Run(_ sink) => sink.Run(_source);
internal sealed class _ : Sink<TSource, TResult>
{
private readonly Func<TSource, int, TResult> _selector;
private int _index;
public _(Func<TSource, int, TResult> selector, IObserver<TResult> observer)
: base(observer)
{
_selector = selector;
}
public override void OnNext(TSource value)
{
TResult result;
try
{
result = _selector(value, checked(_index++));
}
catch (Exception exception)
{
ForwardOnError(exception);
return;
}
ForwardOnNext(result);
}
}
}
}
}