using System.Collections.Generic; namespace System.Reactive.Linq.ObservableImpl { internal sealed class ToDictionary<TSource, TKey, TElement> : Producer<IDictionary<TKey, TElement>, ToDictionary<TSource, TKey, TElement>._> { internal sealed class _ : Sink<TSource, IDictionary<TKey, TElement>> { private readonly Func<TSource, TKey> _keySelector; private readonly Func<TSource, TElement> _elementSelector; private Dictionary<TKey, TElement> _dictionary; public _(ToDictionary<TSource, TKey, TElement> parent, IObserver<IDictionary<TKey, TElement>> observer) : base(observer) { _keySelector = parent._keySelector; _elementSelector = parent._elementSelector; _dictionary = new Dictionary<TKey, TElement>(parent._comparer); } public override void OnNext(TSource value) { try { _dictionary.Add(_keySelector(value), _elementSelector(value)); } catch (Exception error) { _dictionary = null; ForwardOnError(error); } } public override void OnError(Exception error) { _dictionary = null; ForwardOnError(error); } public override void OnCompleted() { Dictionary<TKey, TElement> dictionary = _dictionary; _dictionary = null; ForwardOnNext(dictionary); ForwardOnCompleted(); } } private readonly IObservable<TSource> _source; private readonly Func<TSource, TKey> _keySelector; private readonly Func<TSource, TElement> _elementSelector; private readonly IEqualityComparer<TKey> _comparer; public ToDictionary(IObservable<TSource> source, Func<TSource, TKey> keySelector, Func<TSource, TElement> elementSelector, IEqualityComparer<TKey> comparer) { _source = source; _keySelector = keySelector; _elementSelector = elementSelector; _comparer = comparer; } protected override _ CreateSink(IObserver<IDictionary<TKey, TElement>> observer) { return new _(this, observer); } protected override void Run(_ sink) { sink.Run(_source); } } }