template <class Iterator1, class Iterator2>
auto operator-(
const move_iterator<Iterator1>& x,
const move_iterator<Iterator2>& y) -> decltype(x.base() - y.base());
Returns: x.base() - y.base().
template <class Iterator>
move_iterator<Iterator> operator+(
typename move_iterator<Iterator>::difference_type n, const move_iterator<Iterator>& x);
Returns: x + n.
template <class Iterator>
move_iterator<Iterator> make_move_iterator(const Iterator& i);
Returns: move_iterator<Iterator>(i).