# File lib/bluecloth.rb, line 673
        def transform_headers( str, rs )
                @log.debug " Transforming headers"

                # Setext-style headers:
                #       Header 1
                #       ========
                #  
                #       Header 2
                #       --------
                #
                str.
                        gsub( SetextHeaderRegexp ) {|m|
                                @log.debug "Found setext-style header"
                                title, hdrchar = $1, $2
                                title = apply_span_transforms( title, rs )

                                case hdrchar
                                when '='
                                        %[<h1>#{title}</h1>\n\n]
                                when '-'
                                        %[<h2>#{title}</h2>\n\n]
                                else
                                        title
                                end
                        }.

                        gsub( AtxHeaderRegexp ) {|m|
                                @log.debug "Found ATX-style header"
                                hdrchars, title = $1, $2
                                title = apply_span_transforms( title, rs )

                                level = hdrchars.length
                                %{<h%d>%s</h%d>\n\n} % [ level, title, level ]
                        }
        end