it shouldn't use char* beacuse we need to support other char in this method, such as chat16_t, char32_t... https://github.com/fmtlib/fmt/blob/e719c43cc61f3ef8b6dfc1aea721b76206cb21bc/include/fmt/format.h#L3509 https://github.com/fmtlib/fmt/blob/e719c43cc61f3ef8b6dfc1aea721b76206cb21bc/include/fmt/format.h#L3513