[range.subrange.general] (original) (raw)

The subrange class template combines together an iterator and a sentinel into a single object that models theview concept.

Additionally, it models thesized_range concept when the final template parameter issubrange_kind​::​sized.

namespace std::ranges { template<class From, class To> concept uses-nonqualification-pointer-conversion = is_pointer_v<From> && is_pointer_v<To> && <remove_pointer_t<From>(*)[], remove_pointer_t<To>(*)[]>;template<class From, class To> concept convertible-to-non-slicing = convertible_to<From, To> && <decay_t<From>, decay_t<To>>;template<class T, class U, class V> concept pair-like-convertible-from = <T> && !is_reference_v<T> && pair-like<T> && constructible_from<T, U, V> && convertible-to-non-slicing<U, tuple_element_t<0, T>> && convertible_to<V, tuple_element_t<1, T>>;template<input_or_output_iterator I, sentinel_for<I> S = I, subrange_kind K = sized_sentinel_for<S, I> ? subrange_kind::sized : subrange_kind::unsized> requires (K == subrange_kind::sized || <S, I>) class subrange : public view_interface<subrange<I, S, K>> { private: static constexpr bool StoreSize = K == subrange_kind::sized && <S, I>; I begin_ = I(); S end_ = S(); make-unsigned-like-t<iter_difference_t<I>> size_ = 0; public: subrange() requires default_initializable<I> = default;constexpr subrange(convertible-to-non-slicing<I> auto i, S s) requires (!StoreSize);constexpr subrange(convertible-to-non-slicing<I> auto i, S s,make-unsigned-like-t<iter_difference_t<I>> n) requires (K == subrange_kind::sized);template<different-from<subrange> R> requires borrowed_range<R> && convertible-to-non-slicing<iterator_t<R>, I> && convertible_to<sentinel_t<R>, S> constexpr subrange(R&& r) requires (!StoreSize || sized_range<R>);template<borrowed_range R> requires convertible-to-non-slicing<iterator_t<R>, I> && convertible_to<sentinel_t<R>, S> constexpr subrange(R&& r, make-unsigned-like-t<iter_difference_t<I>> n) requires (K == subrange_kind::sized) : subrange{ranges::begin(r), ranges::end(r), n} {} template<different-from<subrange> PairLike> requires pair-like-convertible-from<PairLike, const I&, const S&> constexpr operator PairLike() const;constexpr I begin() const requires copyable<I>;constexpr I begin() requires (<I>);constexpr S end() const;constexpr bool empty() const;constexpr make-unsigned-like-t<iter_difference_t<I>> size() const requires (K == subrange_kind::sized);constexpr subrange next(iter_difference_t<I> n = 1) const & requires forward_iterator<I>;constexpr subrange next(iter_difference_t<I> n = 1) &&;constexpr subrange prev(iter_difference_t<I> n = 1) const requires bidirectional_iterator<I>;constexpr subrange& advance(iter_difference_t<I> n);};template<input_or_output_iterator I, sentinel_for<I> S> subrange(I, S) -> subrange<I, S>;template<input_or_output_iterator I, sentinel_for<I> S> subrange(I, S, make-unsigned-like-t<iter_difference_t<I>>) -> subrange<I, S, subrange_kind::sized>;template<borrowed_range R> subrange(R&&) -> subrange<iterator_t<R>, sentinel_t<R>,(sized_range<R> || sized_sentinel_for<sentinel_t<R>, iterator_t<R>>) ? subrange_kind::sized : subrange_kind::unsized>;template<borrowed_range R> subrange(R&&, make-unsigned-like-t<range_difference_t<R>>) -> subrange<iterator_t<R>, sentinel_t<R>, subrange_kind::sized>;}