AsyncLockObserver<T>
using System.Reactive.Concurrency;
using System.Runtime.CompilerServices;
namespace System.Reactive
{
    [System.Runtime.CompilerServices.NullableContext(1)]
    [System.Runtime.CompilerServices.Nullable(new byte[] {
        0,
        1
    })]
    internal sealed class AsyncLockObserver<[System.Runtime.CompilerServices.Nullable(2)] T> : ObserverBase<T>
    {
        private readonly AsyncLock _gate;
        private readonly IObserver<T> _observer;
        public AsyncLockObserver(IObserver<T> observer, AsyncLock gate)
        {
            _gate = gate;
            _observer = observer;
        }
        protected override void OnNextCore(T value)
        {
            _gate.Wait<(IObserver<T>, T)>((_observer, value), (Action<(IObserver<T>, T)>)delegate((IObserver<T> _observer, T value) tuple) {
                tuple._observer.OnNext(tuple.value);
            });
        }
        protected override void OnErrorCore(Exception exception)
        {
            _gate.Wait<(IObserver<T>, Exception)>((_observer, exception), (Action<(IObserver<T>, Exception)>)delegate((IObserver<T> _observer, Exception exception) tuple) {
                tuple._observer.OnError(tuple.exception);
            });
        }
        protected override void OnCompletedCore()
        {
            _gate.Wait<IObserver<T>>(_observer, (Action<IObserver<T>>)delegate(IObserver<T> closureObserver) {
                closureObserver.OnCompleted();
            });
        }
    }
}