C++ UTF-8 character literal
From Just Solve the File Format Problem
C++ UTF-8 character literal is a way to represent a single code point in UTF-8 that can be stored in char. It can legitimately be either an ASCII character from with the value 0–127 or C0 Controls Unicode block; if it falls outside of those allowed values, the program is considered to be malformed.
Character literal must use single quotes preceding with the letter u8 (For example u8'a').
