using System.Collections.Generic; namespace System.Reactive.Linq.ObservableImpl { internal sealed class ToList<TSource> : Producer<IList<TSource>, ToList<TSource>._> { internal sealed class _ : Sink<TSource, IList<TSource>> { private List<TSource> _list; public _(IObserver<IList<TSource>> observer) : base(observer) { _list = new List<TSource>(); } public override void OnNext(TSource value) { _list.Add(value); } public override void OnError(Exception error) { _list = null; ForwardOnError(error); } public override void OnCompleted() { List<TSource> list = _list; _list = null; ForwardOnNext(list); ForwardOnCompleted(); } } private readonly IObservable<TSource> _source; public ToList(IObservable<TSource> source) { _source = source; } protected override _ CreateSink(IObserver<IList<TSource>> observer) { return new _(observer); } protected override void Run(_ sink) { sink.Run(_source); } } }