core :: Char :: u8char_len
self
# 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