# Returns `self` removed from its last line terminator (if any).
	#
	# ~~~
	# assert "Hello\n".chomp == "Hello"
	# assert "Hello".chomp   == "Hello"
	#
	# assert "\n".chomp == ""
	# assert "".chomp   == ""
	# ~~~
	#
	# Line terminators are `"\n"`, `"\r\n"` and `"\r"`.
	# A single line terminator, the last one, is removed.
	#
	# ~~~
	# assert "\r\n".chomp     == ""
	# assert "\r\n\n".chomp   == "\r\n"
	# assert "\r\n\r\n".chomp == "\r\n"
	# assert "\r\n\r".chomp   == "\r\n"
	# ~~~
	#
	# Note: unlike with most IO methods like `Reader::read_line`,
	# a single `\r` is considered here to be a line terminator and will be removed.
	fun chomp: SELFTYPE
	do
		var len = length
		if len == 0 then return self
		var l = self.chars.last
		if l == '\r' then
			return substring(0, len-1)
		else if l != '\n' then
			return self
		else if len > 1 and self.chars[len-2] == '\r' then
			return substring(0, len-2)
		else
			return substring(0, len-1)
		end
	end