redef fun add_headline(v, block) do
		# save headline
		var txt = block.block.first_line.as(not null).value
		var id = strip_id(txt)
		var lvl = block.depth
		headlines[id] = new HeadLine(id, txt, lvl)
		v.add "{"#" * lvl} "
		v.emit_in block
		v.addn
	end

	redef fun add_headline(v, block) do
		# save headline
		var line = block.block.first_line
		if line == null then return
		var txt = line.value
		var id = strip_id(txt)
		var lvl = block.depth
		headlines[id] = new HeadLine(id, txt, lvl)
		# output it
		v.add "<h{lvl} id=\"{id}\">"
		v.emit_in block
		v.add "</h{lvl}>\n"
	end

	redef fun add_headline(v, block) do
		var lvl = block.depth
		if lvl == 1 then
			v.add ".SH "
		else if lvl == 2 then
			v.add ".SS "
		else if lvl >= 3 then
			# We use dictionary (titled paragraph) to simulate a 3rd level (or more)
			v.add ".TP\n"
		end
		v.emit_in block
		v.addn
	end

	redef fun add_headline(v, block) do v.emit_in block

	redef fun add_headline(v, block) do
		super
		check_res(block)
	end