def generate(parser, opts={})
      case parser
      when Grammar then gen_parser(parser, opts)
      when RuleSet then gen_rules(parser, opts)
      end
      self
    end
def generate(parser, opts={})
      case parser
      when Grammar then gen_parser(parser, opts)
      when RuleSet then gen_rules(parser, opts)
      end
      self
    end
:nodoc: