reactive/Ix.NET/Source/System.Linq.Async/System/Linq/Operators/AsAsyncEnumerable.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.Collections.Generic;

namespace System.Linq
{
    public static partial class AsyncEnumerable
    {
        // NB: Synchronous LINQ to Objects doesn't hide the implementation of the source either.

        public static IAsyncEnumerable<TSource> AsAsyncEnumerable<TSource>(this IAsyncEnumerable<TSource> source) => source;
    }
}