c void debug_message(String mess)</tt> whose default implementation
prints a message to <tt>System.err</tt>).</p><p>

Based on these routines, invocation of a CUP parser is typically done
with code such as:
</p><pre>      /* create a parsing object */
      parser parser_obj = new parser();

      /* open input files, etc. here */
      Symbol parse_tree = null;

      try {
        if (do_debug_parse)
          parse_tree = parser_obj.debug_parse();
        else
          parse_tree = parser_obj.parse();
 