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CSharp · Console

/Program.cs

using System;
using System.Linq;
using System.Threading.Tasks;

public class Program
{
    public static async Task Main()
    {
        var sequence_A = Enumerable.Range(1, 5).Select(i => $"A{i}").ToAsyncEnumerable();
        var sequence_B = Enumerable.Range(1, 5).Select(i => $"B{i}").ToAsyncEnumerable();
        var sequence_C = Enumerable.Range(1, 5).Select(i => $"C{i}").ToAsyncEnumerable();
        var merged = AsyncEnumerableEx.Merge(sequence_A, sequence_B, sequence_C);
        await foreach (var item in merged) Console.WriteLine(item);
    }
}