Function write_codepoint

include/fmt/format.h:1780–1788

#define FMT_STRING(s) FMT_STRING_IMPL(s, fmt::detail::compile_string, )

template <size_t width, typename Char, typename OutputIt> auto write_codepoint(OutputIt out, char prefix, uint32_t cp)
    -> OutputIt {
    *out++ = static_cast<Char>('\\');
    *out++ = static_cast<Char>(prefix);
    Char buf[width];
    fill_n(buf, width, static_cast<Char>('0'));
    format_uint<4>(buf, cp, width);
    return copy_str<Char>(buf, buf + width, out);
}

template <typename OutputIt, typename Char> auto write_escaped_cp(OutputIt out, const find_escape_result<Char>& escape)
    -> OutputIt {