using System.Runtime.CompilerServices; namespace System.Reactive.Linq.ObservableImpl { [NullableContext(1)] [Nullable(new byte[] { 0, 1 })] internal sealed class FirstBlocking<[Nullable(2)] T> : System.Reactive.Linq.ObservableImpl.BaseBlocking<T> { public override void OnNext(T value) { if (!_hasValue) { _value = value; _hasValue = true; Set(); } } } }