# Escape to include in a Makefile
	#
	# Unfortunately, some characters are not escapable in Makefile.
	# These characters are `;`, `|`, `\`, and the non-printable ones.
	# They will be rendered as `"?{hex}"`.
	fun escape_to_mk: String do
		var b = new Buffer
		for i in [0..length[ do
			var c = chars[i]
			if c == '$' then
				b.append("$$")
			else if c == ':' or c == ' ' or c == '#' then
				b.add('\\')
				b.add(c)
			else if c.code_point < 32 or c == ';' or c == '|' or c == '\\' then
				b.append("?{c.code_point.to_base(16)}")
			else
				b.add(c)
			end
		end
		return b.to_s
	end