using System.Runtime.CompilerServices; namespace System.Reactive.Linq.ObservableImpl { [System.Runtime.CompilerServices.NullableContext(1)] [System.Runtime.CompilerServices.Nullable(new byte[] { 0, 1, 1, 1, 1 })] internal sealed class Scan<[System.Runtime.CompilerServices.Nullable(2)] TSource, [System.Runtime.CompilerServices.Nullable(2)] TAccumulate> : Producer<TAccumulate, Scan<TSource, TAccumulate>._> { [System.Runtime.CompilerServices.Nullable(new byte[] { 0, 1, 1 })] internal sealed class _ : Sink<TSource, TAccumulate> { private readonly Func<TAccumulate, TSource, TAccumulate> _accumulator; private TAccumulate _accumulation; public _(Scan<TSource, TAccumulate> parent, IObserver<TAccumulate> observer) : base(observer) { _accumulator = parent._accumulator; _accumulation = parent._seed; } public override void OnNext(TSource value) { try { _accumulation = _accumulator(_accumulation, value); } catch (Exception error) { ForwardOnError(error); return; } ForwardOnNext(_accumulation); } } private readonly IObservable<TSource> _source; private readonly TAccumulate _seed; private readonly Func<TAccumulate, TSource, TAccumulate> _accumulator; public Scan(IObservable<TSource> source, TAccumulate seed, Func<TAccumulate, TSource, TAccumulate> accumulator) { _source = source; _seed = seed; _accumulator = accumulator; } [return: System.Runtime.CompilerServices.Nullable(new byte[] { 1, 0, 0 })] protected override _ CreateSink(IObserver<TAccumulate> observer) { return new _(this, observer); } protected override void Run([System.Runtime.CompilerServices.Nullable(new byte[] { 1, 0, 0 })] _ sink) { sink.Run(_source); } } }