add_word_pair

# File lib/rdoc/markup/attribute_manager.rb, line 207
  def add_word_pair(start, stop, name)
    raise ArgumentError, "Word flags may not start with '<'" if
      start[0,1] == '<'

    bitmap = @attributes.bitmap_for name

    if start == stop then
      @matching_word_pairs[start] = bitmap
    else
      pattern = /(#{Regexp.escape start})(\S+)(#{Regexp.escape stop})/
      @word_pair_map[pattern] = bitmap
    end

    @protectable << start[0,1]
    @protectable.uniq!
  end