public static void TryCopyToSpan()
        {
            int[] src = { 1, 2, 3 };
            int[] dst = { 99, 100, 101 };

            var  srcBuffer = new ReadOnlyBuffer <int>(src);
            bool success   = srcBuffer.TryCopyTo(dst.AsSpan());

            Assert.True(success);
            Assert.Equal <int>(src, dst);
        }