Function formatted_size

extlibs/fmt/include/fmt/format.h:3486–3488

 */
template <typename... Args>
inline std::size_t formatted_size(string_view format_str, const Args&... args) {
  return format_to(internal::counting_iterator(), format_str, args...).count();
}

template <typename Char, FMT_ENABLE_IF(std::is_same<Char, wchar_t>::value)>
void vprint(std::FILE* f, basic_string_view<Char> format_str,