private boolean Escape_0()
    {
      begin("");
      if (!next("\\u")) return rejectInner();
      if (!HexDigit()) return rejectInner();
      if (!HexDigit()) return rejectInner();
      if (!HexDigit()) return rejectInner();
      if (!HexDigit()) return rejectInner();
      return acceptInner();
    }