Method construct_value

include/experimental/expected.hpp:717–720

            enable_if_t<is_constructible_v<T, Args &&...>> * = nullptr,
            bool NoExcept = is_nothrow_constructible_v<T, Args &&...>>
  void construct_value(Args &&...args) noexcept(NoExcept) {
    new (addressof(base::m_val)) T(std::forward<Args>(args)...);
    base::m_has_val = true;
  }
  template <class... Args,
            enable_if_t<is_constructible_v<E, Args &&...>> * = nullptr,
            bool NoExcept = is_nothrow_constructible_v<E, Args &&...>>