=> Result.Plus(result0, Result.Plus(result1, result2)).Map(TupleHelper.Unfold);
await Task.WhenAny(result1, result2).ConfigureAwait(false);
=> Result.Plus(result0, Result.Plus(result1, result2, mergeFunc.ThrowIfDefault(nameof(mergeFunc))), mergeFunc.ThrowIfDefault(nameof(mergeFunc))).Map(TupleHelper.Unfold);