24 Ranges library [ranges]

24.5 Range utilities [range.utility]

24.5.4 Sub-ranges [range.subrange]

24.5.4.3 Accessors [range.subrange.access]

constexpr I begin() const requires copyable<I>;
Effects: Equivalent to: return begin_­;
[[nodiscard]] constexpr I begin() requires (!copyable<I>);
Effects: Equivalent to: return std​::​move(begin_­);
constexpr S end() const;
Effects: Equivalent to: return end_­;
constexpr bool empty() const;
Effects: Equivalent to: return begin_­ == end_­;
constexpr make-unsigned-like-t<iter_difference_t<I>> size() const requires (K == subrange_kind::sized);
Effects:
  • If StoreSize is true, equivalent to: return size_­;
  • Otherwise, equivalent to: return to-unsigned-like(end_­ - begin_­);
[[nodiscard]] constexpr subrange next(iter_difference_t<I> n = 1) const & requires forward_­iterator<I>;
Effects: Equivalent to: auto tmp = *this; tmp.advance(n); return tmp;
[[nodiscard]] constexpr subrange next(iter_difference_t<I> n = 1) &&;
Effects: Equivalent to: advance(n); return std::move(*this);
[[nodiscard]] constexpr subrange prev(iter_difference_t<I> n = 1) const requires bidirectional_­iterator<I>;
Effects: Equivalent to: auto tmp = *this; tmp.advance(-n); return tmp;
constexpr subrange& advance(iter_difference_t<I> n);
Effects: Equivalent to: if constexpr (bidirectional_iterator<I>) { if (n < 0) { ranges::advance(begin_, n); if constexpr (StoreSize) size_ += to-unsigned-like(-n); return *this; } } auto d = n - ranges::advance(begin_, n, end_); if constexpr (StoreSize) size_ -= to-unsigned-like(d); return *this;
template<size_t N, class I, class S, subrange_kind K> requires ((N == 0 && copyable<I>) || N == 1) constexpr auto get(const subrange<I, S, K>& r); template<size_t N, class I, class S, subrange_kind K> requires (N < 2) constexpr auto get(subrange<I, S, K>&& r);
Effects: Equivalent to: if constexpr (N == 0) return r.begin(); else return r.end();