constexpr
iterator
operator‐(
    iterator i,
    difference_type n)
requires std::ranges::random_access_range<Base>;

constexpr
difference_type
operator‐(
    iterator const& x,
    iterator const& y)
requires std::sized_sentinel_for<std::ranges::iterator_t<Base>,
                                             std::ranges::iterator_t<Base> >;

template<bool OtherConst>
requires std::sized_sentinel_for<
                std::ranges::sentinel_t<Base>,
                std::ranges::iterator_t<detail::maybe_const<OtherConst, V> > >
constexpr
std::ranges::range_difference_t</* implementation-defined */>
operator‐(
    sentinel const& y,
    iterator<OtherConst> const& x);

template<bool OtherConst>
requires std::sized_sentinel_for<
                std::ranges::sentinel_t<Base>,
                std::ranges::iterator_t<detail::maybe_const<OtherConst, V> > >
constexpr
std::ranges::range_difference_t</* implementation-defined */>
operator‐(
    iterator<OtherConst> const& x,
    sentinel const& y);