Function push_back

include/fmt/args.h:153–158

   *     std::string result = fmt::vformat("{} and {} and {}", store);
   */
  template <typename T> void push_back(const T& arg) {
    if FMT_CONSTEXPR20 (need_copy<T>::value)
      emplace_arg(dynamic_args_.push<stored_t<T>>(arg));
    else
      emplace_arg(detail::unwrap(arg));
  }

  /**
   * Adds a reference to the argument into the dynamic store for later passing