namespace System.Reactive.Linq.ObservableImpl { internal sealed class MinInt64Nullable : Producer<long?, MinInt64Nullable._> { internal sealed class _ : IdentitySink<long?> { private long? _lastValue; public _(IObserver<long?> observer) : base(observer) { } public override void OnNext(long? value) { if (value.HasValue) { if (_lastValue.HasValue) { long? nullable = value; long? lastValue = _lastValue; if ((nullable.GetValueOrDefault() < lastValue.GetValueOrDefault()) & (nullable.HasValue & lastValue.HasValue)) _lastValue = value; } else _lastValue = value; } } public override void OnCompleted() { ForwardOnNext(_lastValue); ForwardOnCompleted(); } } private readonly IObservable<long?> _source; public MinInt64Nullable(IObservable<long?> source) { _source = source; } protected override _ CreateSink(IObserver<long?> observer) { return new _(observer); } protected override void Run(_ sink) { sink.Run(_source); } } }