template<class Iterator1, class Iterator2>
constexpr auto operator-(
const reverse_iterator<Iterator1>& x,
const reverse_iterator<Iterator2>& y) -> decltype(y.base() - x.base());
template<class Iterator>
constexpr reverse_iterator<Iterator> operator+(
iter_difference_t<Iterator> n,
const reverse_iterator<Iterator>& x);
friend constexpr iter_rvalue_reference_t<Iterator>
iter_move(const reverse_iterator& i) noexcept(see below);
template<indirectly_swappable<Iterator> Iterator2>
friend constexpr void
iter_swap(const reverse_iterator& x,
const reverse_iterator<Iterator2>& y) noexcept(see below);
template<class Iterator>
constexpr reverse_iterator<Iterator> make_reverse_iterator(Iterator i);