reactive/Ix.NET/Source/System.Linq.Async/System/Linq/Operators/Range.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
    {
        public static IAsyncEnumerable<int> Range(int start, int count)
        {
            if (count < 0)
                throw new ArgumentOutOfRangeException(nameof(count));

            return Enumerable.Range(start, count).ToAsyncEnumerable();
        }
    }
}