class RDoc::Markup::ToBs

def convert_string string
  return string unless string.respond_to? :chars # your ruby is lame
  return string unless @in_b or @in_em
  chars = if @in_b then
            string.chars.map do |char| "#{char}\b#{char}" end
          elsif @in_em then
            string.chars.map do |char| "_\b#{char}" end
          end
  chars.join
end