reactive/Ix.NET/Source/System.Interactive.Async/TaskExt.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. 

namespace System.Threading.Tasks
{
    internal static class TaskExt
    {
        public static readonly ValueTask<bool> Never = new ValueTask<bool>(new TaskCompletionSource<bool>().Task);
    }
}