[range.slide.iterator] (original) (raw)

25 Ranges library [ranges]

25.7 Range adaptors [range.adaptors]

25.7.30 Slide view [range.slide]

25.7.30.3 Class template slide_view​::​iterator [range.slide.iterator]

namespace std::ranges { template<forward_range V> requires view<V> template<bool Const> class slide_view<V>::iterator { using Base = maybe-const<Const, V>; iterator_t<_Base_> current_ = iterator_t<_Base_>(); iterator_t<_Base_> last_ele_ = iterator_t<_Base_>(); range_difference_t<_Base_> n_ = 0; constexpr iterator(iterator_t<_Base_> current, range_difference_t<_Base_> n) requires (_slide-caches-first_<_Base_>);constexpr iterator(iterator_t<_Base_> current, iterator_t<_Base_> last_ele, range_difference_t<_Base_> n) requires slide-caches-first<_Base_>;public: using iterator_category = input_iterator_tag;using iterator_concept = see below;using value_type = decltype(views::counted(current_, n_));using difference_type = range_difference_t<_Base_>;iterator() = default;constexpr iterator(iterator<!Const> i) requires Const && convertible_to<iterator_t<V>, iterator_t<_Base_>>;constexpr auto operator*() const;constexpr iterator& operator++();constexpr iterator operator++(int);constexpr iterator& operator--() requires bidirectional_range<_Base_>;constexpr iterator operator--(int) requires bidirectional_range<_Base_>;constexpr iterator& operator+=(difference_type x) requires random_access_range<_Base_>;constexpr iterator& operator-=(difference_type x) requires random_access_range<_Base_>;constexpr auto operator[](difference_type n) const requires random_access_range<_Base_>;friend constexpr bool operator==(const iterator& x, const iterator& y);friend constexpr bool operator<(const _iterator_& x, const _iterator_& y) requires random_access_range<_Base_>;friend constexpr bool operator>(const iterator& x, const iterator& y) requires random_access_range<_Base_>;friend constexpr bool operator<=(const _iterator_& x, const _iterator_& y) requires random_access_range<_Base_>;friend constexpr bool operator>=(const iterator& x, const iterator& y) requires random_access_range<_Base_>;friend constexpr auto operator<=>(const iterator& x, const iterator& y) requires random_access_range<_Base_> && three_way_comparable<iterator_t<_Base_>>;friend constexpr iterator operator+(const iterator& i, difference_type n) requires random_access_range<_Base_>;friend constexpr iterator operator+(difference_type n, const iterator& i) requires random_access_range<_Base_>;friend constexpr iterator operator-(const iterator& i, difference_type n) requires random_access_range<_Base_>;friend constexpr difference_type operator-(const iterator& x, const iterator& y) requires sized_sentinel_for<iterator_t<_Base_>, iterator_t<_Base_>>;};}

_iterator_​::​iterator_concept is defined as follows:

If the invocation of any non-const member function of _iterator_exits via an exception, the iterator acquires a singular value.

constexpr _iterator_(iterator_t<_Base_> current, range_difference_t<_Base_> n) requires (![_slide-caches-first_](range.slide.view#concept:slide-caches-first "25.7.30.2 Class template slide_­view [range.slide.view]")<_Base_>);

Effects: Initializes current_ with current and_n__ with n.

constexpr _iterator_(iterator_t<_Base_> current, iterator_t<_Base_> last_ele, range_difference_t<_Base_> n) requires [_slide-caches-first_](range.slide.view#concept:slide-caches-first "25.7.30.2 Class template slide_­view [range.slide.view]")<_Base_>;

Effects: Initializes current_ with current,last_ele_ with last_ele, and_n__ with n.

constexpr _iterator_(_iterator_<!Const> i) requires Const && [convertible_to](concept.convertible#concept:convertible%5Fto "18.4.4 Concept convertible_­to [concept.convertible]")<iterator_t<V>, iterator_t<_Base_>>;

Effects: Initializes current_ with std​::​move(i.current_) and_n__ with i.n_.

[Note 1:

iterator<true> can only be formed when Base models slide-caches-nothing, in which case last_ele_ is not present.

— _end note_]

constexpr auto operator*() const;

Returns: views​::​counted(current_, n_).

constexpr _iterator_& operator++();

Preconditions: current_ and last_ele_ (if present) are incrementable.

Postconditions: current_ and last_ele_ (if present) are each equal to ranges​::​next(i), where i is the value of that data member before the call.

constexpr _iterator_ operator++(int);

Effects: Equivalent to:auto tmp = *this;++*this;return tmp;

Preconditions: current_ and last_ele_ (if present) are decrementable.

Postconditions: current_ and last_ele_ (if present) are each equal to ranges​::​prev(i), where i is the value of that data member before the call.

Effects: Equivalent to:auto tmp = *this;--*this;return tmp;

Preconditions: current_ + x and last_ele_ + x (if last_ele_ is present) have well-defined behavior.

Postconditions: current_ and last_ele_ (if present) are each equal to i + x, where i is the value of that data member before the call.

Preconditions: current_ - x and last_ele_ - x (if last_ele_ is present) have well-defined behavior.

Postconditions: current_ and last_ele_ (if present) are each equal to i - x, where i is the value of that data member before the call.

Effects: Equivalent to: return views​::​counted(current_ + n, n_);

friend constexpr bool operator==(const _iterator_& x, const _iterator_& y);

Returns: If last_ele_ is present,x.last_ele_ == y.last_ele_; otherwise, x.current_ == y.current_.

friend constexpr bool operator<(const _iterator_& x, const _iterator_& y) requires [random_access_range](range.refinements#concept:random%5Faccess%5Frange "25.4.5 Other range refinements [range.refinements]")<_Base_>;

Returns: x.current_ < y.current_.

friend constexpr bool operator>(const _iterator_& x, const _iterator_& y) requires [random_access_range](range.refinements#concept:random%5Faccess%5Frange "25.4.5 Other range refinements [range.refinements]")<_Base_>;

Effects: Equivalent to: return y < x;

friend constexpr bool operator<=(const _iterator_& x, const _iterator_& y) requires [random_access_range](range.refinements#concept:random%5Faccess%5Frange "25.4.5 Other range refinements [range.refinements]")<_Base_>;

Effects: Equivalent to: return !(y < x);

friend constexpr bool operator>=(const _iterator_& x, const _iterator_& y) requires [random_access_range](range.refinements#concept:random%5Faccess%5Frange "25.4.5 Other range refinements [range.refinements]")<_Base_>;

Effects: Equivalent to: return !(x < y);

Returns: x.current_ <=> y.current_.

friend constexpr _iterator_ operator+(const _iterator_& i, difference_type n) requires [random_access_range](range.refinements#concept:random%5Faccess%5Frange "25.4.5 Other range refinements [range.refinements]")<_Base_>;friend constexpr _iterator_ operator+(difference_type n, const _iterator_& i) requires [random_access_range](range.refinements#concept:random%5Faccess%5Frange "25.4.5 Other range refinements [range.refinements]")<_Base_>;

Effects: Equivalent to:auto r = i; r += n;return r;

friend constexpr _iterator_ operator-(const _iterator_& i, difference_type n) requires [random_access_range](range.refinements#concept:random%5Faccess%5Frange "25.4.5 Other range refinements [range.refinements]")<_Base_>;

Effects: Equivalent to:auto r = i; r -= n;return r;

friend constexpr difference_type operator-(const _iterator_& x, const _iterator_& y) requires [sized_sentinel_for](iterator.concept.sizedsentinel#concept:sized%5Fsentinel%5Ffor "24.3.4.8 Concept sized_­sentinel_­for [iterator.concept.sizedsentinel]")<iterator_t<_Base_>, iterator_t<_Base_>>;

Returns: If last_ele_ is present,x.last_ele_ - y.last_ele_; otherwise, x.current_ - y.current_.