Function fprintf

extlibs/fmt/include/fmt/printf.h:651–655

template <typename S, typename... Args,
          typename Char = enable_if_t<internal::is_string<S>::value, char_t<S>>>
inline int fprintf(std::FILE* f, const S& format, const Args&... args) {
  using context = basic_printf_context_t<Char>;
  return vfprintf(f, to_string_view(format),
                  make_format_args<context>(args...));
}

template <typename S, typename Char = char_t<S>>
inline int vprintf(