# Length of `self` in a UTF-8 String
	fun u8char_len: Int do
		var c = self.code_point
		if c < 0x80 then return 1
		if c <= 0x7FF then return 2
		if c <= 0xFFFF then return 3
		if c <= 0x10FFFF then return 4
		# Bad character format
		return 1
	end