# File lib/rdoc/markup/formatter.rb, line 138
  def on_tags res, item
    attr_mask = item.turn_on
    return if attr_mask.zero?

    @attr_tags.each do |tag|
      if attr_mask & tag.bit != 0 then
        res << annotate(tag.on)
        @in_tt += 1 if tt? tag
      end
    end
  end