using System.Runtime.CompilerServices; namespace System.Reactive.Linq.ObservableImpl { [System.Runtime.CompilerServices.NullableContext(1)] [System.Runtime.CompilerServices.Nullable(new byte[] { 0, 1 })] internal sealed class SumDoubleNullable : Producer<double?, SumDoubleNullable._> { [System.Runtime.CompilerServices.NullableContext(0)] internal sealed class _ : IdentitySink<double?> { private double _sum; [System.Runtime.CompilerServices.NullableContext(1)] public _(IObserver<double?> observer) : base(observer) { } public override void OnNext(double? value) { if (value.HasValue) _sum += value.Value; } public override void OnCompleted() { ForwardOnNext(_sum); ForwardOnCompleted(); } } private readonly IObservable<double?> _source; public SumDoubleNullable(IObservable<double?> source) { _source = source; } protected override _ CreateSink(IObserver<double?> observer) { return new _(observer); } protected override void Run(_ sink) { sink.Run(_source); } } }