reactive/AsyncRx.NET/System.Reactive.Bcl/System/IAwaiter.cs

// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the Apache 2.0 License.
// See the LICENSE file in the project root for more information. 

using System.Runtime.CompilerServices;

namespace System
{
    public interface IAwaiter : INotifyCompletion
    {
        bool IsCompleted { get; }
        void GetResult();
    }

    public interface IAwaiter<T> : INotifyCompletion
    {
        bool IsCompleted { get; }
        T GetResult();
    }
}