text: public override BytesRef Add(BytesRef prefix, BytesRef output){Debug.Assert(prefix != null);Debug.Assert(output != null);if (prefix == NO_OUTPUT){return output;}else if (output == NO_OUTPUT){return prefix;}else{Debug.Assert(prefix.Length > 0);Debug.Assert(output.Length > 0);BytesRef result = new BytesRef(prefix.Length + output.Length);Array.Copy(prefix.Bytes, prefix.Offset, result.Bytes, 0, prefix.Length);Array.Copy(output.Bytes, output.Offset, result.Bytes, prefix.Length, output.Length);result.Length = prefix.Length + output.Length;return result;}}