depish/cppdraft_translate
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
Files
043225d523e821bfa89efb15f5074f0465fb7edf
cppdraft_translate/cppdraft/range/adjacent.md
Leonov Artur (Depish) 043225d523 Init
2025-10-25 03:02:53 +03:00

533 lines
30 KiB
Markdown
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

[range.adjacent]
# 25 Ranges library [[ranges]](./#ranges)
## 25.7 Range adaptors [[range.adaptors]](range.adaptors#range.adjacent)
### 25.7.27 Adjacent view [range.adjacent]
#### [25.7.27.1](#overview) Overview [[range.adjacent.overview]](range.adjacent.overview)
[1](#overview-1)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12539)
adjacent_view takes a view and
produces a view whose Mth element is
a tuple of references to
the Mth through (M+N−1)th elements of
the original view[.](#overview-1.sentence-1)
If the original view has fewer than N elements, the resulting view is empty[.](#overview-1.sentence-2)
[2](#overview-2)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12547)
The name views​::​adjacent<N> denotes
a range adaptor object ([[range.adaptor.object]](range.adaptor.object "25.7.2 Range adaptor objects"))[.](#overview-2.sentence-1)
Given a subexpression E and a constant expression N,
the expression views​::​adjacent<N>(E) is expression-equivalent to
- [(2.1)](#overview-2.1)
((void)E, auto(views​::​empty<tuple<>>)) if N is equal to 0 anddecltype((E)) models [forward_range](range.refinements#concept:forward_range "25.4.6 Other range refinements [range.refinements]"),
- [(2.2)](#overview-2.2)
otherwise, adjacent_view<views​::​all_t<decltype((E))>, N>(E)[.](#overview-2.sentence-2)
[*Example [1](#overview-example-1)*: vector v = {1, 2, 3, 4};
for (auto i : v | views::adjacent<2>) { cout << "(" << std::get<0>(i) << ", " << std::get<1>(i) << ") "; // prints (1, 2) (2, 3) (3, 4)} — *end example*]
[3](#overview-3)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12572)
Define *REPEAT*(T, N) as a pack of N types,
each of which denotes the same type as T[.](#overview-3.sentence-1)
#### [25.7.27.2](#view) Class template adjacent_view [[range.adjacent.view]](range.adjacent.view)
[🔗](#lib:adjacent_view)
namespace std::ranges {template<[forward_range](range.refinements#concept:forward_range "25.4.6 Other range refinements [range.refinements]") V, size_t N>requires [view](range.view#concept:view "25.4.5 Views [range.view]")<V> && (N > 0)class adjacent_view : public view_interface<adjacent_view<V, N>> { V *base_* = V(); // *exposition only*// [[range.adjacent.iterator]](#iterator "25.7.27.3 Class template adjacent_­view​::​iterator"), class template adjacent_view​::​*iterator*template<bool> class *iterator*; // *exposition only*// [[range.adjacent.sentinel]](#sentinel "25.7.27.4 Class template adjacent_­view​::​sentinel"), class template adjacent_view​::​*sentinel*template<bool> class *sentinel*; // *exposition only*struct *as-sentinel*{}; // *exposition only*public: adjacent_view() requires [default_initializable](concept.default.init#concept:default_initializable "18.4.12 Concept default_­initializable [concept.default.init]")<V> = default; constexpr explicit adjacent_view(V base); constexpr V base() const & requires [copy_constructible](concept.copyconstructible#concept:copy_constructible "18.4.14 Concept copy_­constructible [concept.copyconstructible]")<V> { return *base_*; }constexpr V base() && { return std::move(*base_*); }constexpr auto begin() requires (![*simple-view*](range.utility.helpers#concept:simple-view "25.5.2 Helper concepts [range.utility.helpers]")<V>) {return *iterator*<false>(ranges::begin(*base_*), ranges::end(*base_*)); }constexpr auto begin() const requires [range](range.range#concept:range "25.4.2 Ranges [range.range]")<const V> {return *iterator*<true>(ranges::begin(*base_*), ranges::end(*base_*)); }constexpr auto end() requires (![*simple-view*](range.utility.helpers#concept:simple-view "25.5.2 Helper concepts [range.utility.helpers]")<V>) {if constexpr ([common_range](range.refinements#concept:common_range "25.4.6 Other range refinements [range.refinements]")<V>) {return *iterator*<false>(*as-sentinel*{}, ranges::begin(*base_*), ranges::end(*base_*)); } else {return *sentinel*<false>(ranges::end(*base_*)); }}constexpr auto end() const requires [range](range.range#concept:range "25.4.2 Ranges [range.range]")<const V> {if constexpr ([common_range](range.refinements#concept:common_range "25.4.6 Other range refinements [range.refinements]")<const V>) {return *iterator*<true>(*as-sentinel*{}, ranges::begin(*base_*), ranges::end(*base_*)); } else {return *sentinel*<true>(ranges::end(*base_*)); }}constexpr auto size() requires [sized_range](range.sized#concept:sized_range "25.4.4 Sized ranges [range.sized]")<V>; constexpr auto size() const requires [sized_range](range.sized#concept:sized_range "25.4.4 Sized ranges [range.sized]")<const V>; constexpr auto reserve_hint() requires [approximately_sized_range](range.approximately.sized#concept:approximately_sized_range "25.4.3 Approximately sized ranges [range.approximately.sized]")<V>; constexpr auto reserve_hint() const requires [approximately_sized_range](range.approximately.sized#concept:approximately_sized_range "25.4.3 Approximately sized ranges [range.approximately.sized]")<const V>; };}
[🔗](#lib:adjacent_view,constructor)
`constexpr explicit adjacent_view(V base);
`
[1](#view-1)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12642)
*Effects*: Initializes *base_* with std​::​move(base)[.](#view-1.sentence-1)
[🔗](#lib:size,adjacent_view)
`constexpr auto size() requires [sized_range](range.sized#concept:sized_range "25.4.4 Sized ranges [range.sized]")<V>;
constexpr auto size() const requires [sized_range](range.sized#concept:sized_range "25.4.4 Sized ranges [range.sized]")<const V>;
`
[2](#view-2)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12654)
*Effects*: Equivalent to:using ST = decltype(ranges::size(*base_*));using CT = common_type_t<ST, size_t>;auto sz = static_cast<CT>(ranges::size(*base_*));
sz -= std::min<CT>(sz, N - 1);return static_cast<ST>(sz);
[🔗](#lib:reserve_hint,adjacent_view)
`constexpr auto reserve_hint() requires [approximately_sized_range](range.approximately.sized#concept:approximately_sized_range "25.4.3 Approximately sized ranges [range.approximately.sized]")<V>;
constexpr auto reserve_hint() const requires [approximately_sized_range](range.approximately.sized#concept:approximately_sized_range "25.4.3 Approximately sized ranges [range.approximately.sized]")<const V>;
`
[3](#view-3)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12673)
*Effects*: Equivalent to:using DT = range_difference_t<decltype((*base_*))>;using CT = common_type_t<DT, size_t>;auto sz = static_cast<CT>(ranges::reserve_hint(*base_*));
sz -= std::min<CT>(sz, N - 1);return *to-unsigned-like*(sz);
#### [25.7.27.3](#iterator) Class template adjacent_view​::​*iterator* [[range.adjacent.iterator]](range.adjacent.iterator)
[🔗](#lib:adjacent_view::iterator)
namespace std::ranges {template<[forward_range](range.refinements#concept:forward_range "25.4.6 Other range refinements [range.refinements]") V, size_t N>requires [view](range.view#concept:view "25.4.5 Views [range.view]")<V> && (N > 0)template<bool Const>class adjacent_view<V, N>::*iterator* {using *Base* = *maybe-const*<Const, V>; // *exposition only* array<iterator_t<*Base*>, N> *current_* = array<iterator_t<*Base*>, N>(); // *exposition only*constexpr *iterator*(iterator_t<*Base*> first, sentinel_t<*Base*> last); // *exposition only*constexpr *iterator*(*as-sentinel*, iterator_t<*Base*> first, iterator_t<*Base*> last); // *exposition only*public:using iterator_category = input_iterator_tag; using iterator_concept = *see below*; using value_type = tuple<*REPEAT*(range_value_t<*Base*>, N)...>; using difference_type = range_difference_t<*Base*>; *iterator*() = default; constexpr *iterator*(*iterator*<!Const> i)requires Const && [convertible_to](concept.convertible#concept:convertible_to "18.4.4 Concept convertible_­to [concept.convertible]")<iterator_t<V>, iterator_t<*Base*>>; constexpr auto operator*() const; constexpr *iterator*& operator++(); constexpr *iterator* operator++(int); constexpr *iterator*& operator--() requires [bidirectional_range](range.refinements#concept:bidirectional_range "25.4.6 Other range refinements [range.refinements]")<*Base*>; constexpr *iterator* operator--(int) requires [bidirectional_range](range.refinements#concept:bidirectional_range "25.4.6 Other range refinements [range.refinements]")<*Base*>; constexpr *iterator*& operator+=(difference_type x)requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<*Base*>; constexpr *iterator*& operator-=(difference_type x)requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<*Base*>; constexpr auto operator[](difference_type n) constrequires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<*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](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<*Base*>; friend constexpr bool operator>(const *iterator*& x, const *iterator*& y)requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<*Base*>; friend constexpr bool operator<=(const *iterator*& x, const *iterator*& y)requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<*Base*>; friend constexpr bool operator>=(const *iterator*& x, const *iterator*& y)requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<*Base*>; friend constexpr auto operator<=>(const *iterator*& x, const *iterator*& y)requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<*Base*> &&[three_way_comparable](cmp.concept#concept:three_way_comparable "17.12.4 Concept three_­way_­comparable [cmp.concept]")<iterator_t<*Base*>>; friend constexpr *iterator* operator+(const *iterator*& i, difference_type n)requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<*Base*>; friend constexpr *iterator* operator+(difference_type n, const *iterator*& i)requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<*Base*>; friend constexpr *iterator* operator-(const *iterator*& i, difference_type n)requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<*Base*>; friend constexpr difference_type operator-(const *iterator*& x, const *iterator*& y)requires [sized_sentinel_for](iterator.concept.sizedsentinel#concept:sized_sentinel_for "24.3.4.8 Concept sized_­sentinel_­for [iterator.concept.sizedsentinel]")<iterator_t<*Base*>, iterator_t<*Base*>>; friend constexpr auto iter_move(const *iterator*& i) noexcept(*see below*); friend constexpr void iter_swap(const *iterator*& l, const *iterator*& r) noexcept(*see below*)requires [indirectly_swappable](alg.req.ind.swap#concept:indirectly_swappable "24.3.7.4 Concept indirectly_­swappable [alg.req.ind.swap]")<iterator_t<*Base*>>; };}
[1](#iterator-1)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12753)
*iterator*​::​iterator_concept is defined as follows:
- [(1.1)](#iterator-1.1)
If *Base* models [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]"),
then iterator_concept denotes random_access_iterator_tag[.](#iterator-1.1.sentence-1)
- [(1.2)](#iterator-1.2)
Otherwise, if *Base* models [bidirectional_range](range.refinements#concept:bidirectional_range "25.4.6 Other range refinements [range.refinements]"),
then iterator_concept denotes bidirectional_iterator_tag[.](#iterator-1.2.sentence-1)
- [(1.3)](#iterator-1.3)
Otherwise, iterator_concept denotes forward_iterator_tag[.](#iterator-1.3.sentence-1)
[2](#iterator-2)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12766)
If the invocation of any non-const member function of *iterator* exits via an exception, the *iterator* acquires a singular value[.](#iterator-2.sentence-1)
[🔗](#lib:adjacent_view::iterator,constructor)
`constexpr iterator(iterator_t<Base> first, sentinel_t<Base> last);
`
[3](#iterator-3)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12776)
*Postconditions*: *current_*[0] == first is true, and
for every integer 1≤i<N,*current_*[i] == ranges​::​next(*current_*[i-1], 1, last) is true[.](#iterator-3.sentence-1)
[🔗](#lib:adjacent_view::iterator,constructor_)
`constexpr iterator(as-sentinel, iterator_t<Base> first, iterator_t<Base> last);
`
[4](#iterator-4)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12790)
*Postconditions*: If *Base* does not model [bidirectional_range](range.refinements#concept:bidirectional_range "25.4.6 Other range refinements [range.refinements]"),
each element of *current_* is equal to *last*[.](#iterator-4.sentence-1)
Otherwise, *current_*[N-1] == last is true, and
for every integer 0≤i<(N−1),*current_*[i] == ranges​::​prev(*current_*[i+1], 1, first) is true[.](#iterator-4.sentence-2)
[🔗](#lib:adjacent_view::iterator,constructor__)
`constexpr iterator(iterator<!Const> i)
requires Const && [convertible_to](concept.convertible#concept:convertible_to "18.4.4 Concept convertible_­to [concept.convertible]")<iterator_t<V>, iterator_t<Base>>;
`
[5](#iterator-5)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12807)
*Effects*: Initializes each element of *current_* with the corresponding element of i.*current_* as an xvalue[.](#iterator-5.sentence-1)
[🔗](#lib:operator*,adjacent_view::iterator)
`constexpr auto operator*() const;
`
[6](#iterator-6)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12819)
*Effects*: Equivalent to:return *tuple-transform*([](auto& i) -> decltype(auto) { return *i; }, *current_*);
[🔗](#lib:operator++,adjacent_view::iterator)
`constexpr iterator& operator++();
`
[7](#iterator-7)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12833)
*Preconditions*: *current_*.back() is incrementable[.](#iterator-7.sentence-1)
[8](#iterator-8)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12837)
*Postconditions*: Each element of *current_* is equal to ranges​::​next(i),
where i is the value of that element before the call[.](#iterator-8.sentence-1)
[9](#iterator-9)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12842)
*Returns*: *this[.](#iterator-9.sentence-1)
[🔗](#lib:operator++,adjacent_view::iterator_)
`constexpr iterator operator++(int);
`
[10](#iterator-10)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12853)
*Effects*: Equivalent to:auto tmp = *this;++*this;return tmp;
[🔗](#lib:operator--,adjacent_view::iterator)
`constexpr iterator& operator--() requires [bidirectional_range](range.refinements#concept:bidirectional_range "25.4.6 Other range refinements [range.refinements]")<Base>;
`
[11](#iterator-11)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12869)
*Preconditions*: *current_*.front() is decrementable[.](#iterator-11.sentence-1)
[12](#iterator-12)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12873)
*Postconditions*: Each element of *current_* is equal to ranges​::​prev(i),
where i is the value of that element before the call[.](#iterator-12.sentence-1)
[13](#iterator-13)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12878)
*Returns*: *this[.](#iterator-13.sentence-1)
[🔗](#lib:operator--,adjacent_view::iterator_)
`constexpr iterator operator--(int) requires [bidirectional_range](range.refinements#concept:bidirectional_range "25.4.6 Other range refinements [range.refinements]")<Base>;
`
[14](#iterator-14)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12889)
*Effects*: Equivalent to:auto tmp = *this;--*this;return tmp;
[🔗](#lib:operator+=,adjacent_view::iterator)
`constexpr iterator& operator+=(difference_type x)
requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<Base>;
`
[15](#iterator-15)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12906)
*Preconditions*: *current_*.back() + x has well-defined behavior[.](#iterator-15.sentence-1)
[16](#iterator-16)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12910)
*Postconditions*: Each element of *current_* is equal to i + x,
where i is the value of that element before the call[.](#iterator-16.sentence-1)
[17](#iterator-17)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12915)
*Returns*: *this[.](#iterator-17.sentence-1)
[🔗](#lib:operator-=,adjacent_view::iterator)
`constexpr iterator& operator-=(difference_type x)
requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<Base>;
`
[18](#iterator-18)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12927)
*Preconditions*: *current_*.front() - x has well-defined behavior[.](#iterator-18.sentence-1)
[19](#iterator-19)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12931)
*Postconditions*: Each element of *current_* is equal to i - x,
where i is the value of that element before the call[.](#iterator-19.sentence-1)
[20](#iterator-20)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12936)
*Returns*: *this[.](#iterator-20.sentence-1)
[🔗](#lib:operator%5b%5d,adjacent_view::iterator)
`constexpr auto operator[](difference_type n) const
requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<Base>;
`
[21](#iterator-21)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12948)
*Effects*: Equivalent to:return *tuple-transform*([&](auto& i) -> decltype(auto) { return i[n]; }, *current_*);
[🔗](#lib:operator==,adjacent_view::iterator)
`friend constexpr bool operator==(const iterator& x, const iterator& y);
`
[22](#iterator-22)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12962)
*Returns*: x.*current_*.back() == y.*current_*.back()[.](#iterator-22.sentence-1)
[🔗](#lib:operator%3c,adjacent_view::iterator)
`friend constexpr bool operator<(const iterator& x, const iterator& y)
requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<Base>;
`
[23](#iterator-23)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12974)
*Returns*: x.*current_*.back() < y.*current_*.back()[.](#iterator-23.sentence-1)
[🔗](#lib:operator%3e,adjacent_view::iterator)
`friend constexpr bool operator>(const iterator& x, const iterator& y)
requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<Base>;
`
[24](#iterator-24)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12986)
*Effects*: Equivalent to: return y < x;
[🔗](#lib:operator%3c=,adjacent_view::iterator)
`friend constexpr bool operator<=(const iterator& x, const iterator& y)
requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<Base>;
`
[25](#iterator-25)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L12998)
*Effects*: Equivalent to: return !(y < x);
[🔗](#lib:operator%3e=,adjacent_view::iterator)
`friend constexpr bool operator>=(const iterator& x, const iterator& y)
requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<Base>;
`
[26](#iterator-26)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13010)
*Effects*: Equivalent to: return !(x < y);
[🔗](#lib:operator%3c=%3e,adjacent_view::iterator)
`friend constexpr auto operator<=>(const iterator& x, const iterator& y)
requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<Base> &&
[three_way_comparable](cmp.concept#concept:three_way_comparable "17.12.4 Concept three_­way_­comparable [cmp.concept]")<iterator_t<Base>>;
`
[27](#iterator-27)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13023)
*Returns*: x.*current_*.back() <=> y.*current_*.back()[.](#iterator-27.sentence-1)
[🔗](#lib:operator+,adjacent_view::iterator)
`friend constexpr iterator operator+(const iterator& i, difference_type n)
requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<Base>;
friend constexpr iterator operator+(difference_type n, const iterator& i)
requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<Base>;
`
[28](#iterator-28)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13037)
*Effects*: Equivalent to:auto r = i;
r += n;return r;
[🔗](#lib:operator-,adjacent_view::iterator)
`friend constexpr iterator operator-(const iterator& i, difference_type n)
requires [random_access_range](range.refinements#concept:random_access_range "25.4.6 Other range refinements [range.refinements]")<Base>;
`
[29](#iterator-29)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13054)
*Effects*: Equivalent to:auto r = i;
r -= n;return r;
[🔗](#lib:operator-,adjacent_view::iterator_)
`friend constexpr difference_type operator-(const iterator& x, const iterator& y)
requires [sized_sentinel_for](iterator.concept.sizedsentinel#concept:sized_sentinel_for "24.3.4.8 Concept sized_­sentinel_­for [iterator.concept.sizedsentinel]")<iterator_t<Base>, iterator_t<Base>>;
`
[30](#iterator-30)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13071)
*Effects*: Equivalent to:return x.*current_*.back() - y.*current_*.back();
[🔗](#lib:iter_move,adjacent_view::iterator)
`friend constexpr auto iter_move(const iterator& i) noexcept(see below);
`
[31](#iterator-31)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13083)
*Effects*: Equivalent to:return *tuple-transform*(ranges​::​iter_move, i.*current_*);
[32](#iterator-32)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13088)
*Remarks*: The exception specification is equivalent to:noexcept(ranges::iter_move(declval<const iterator_t<*Base*>&>())) && is_nothrow_move_constructible_v<range_rvalue_reference_t<*Base*>>
[🔗](#lib:iter_swap,adjacent_view::iterator)
`friend constexpr void iter_swap(const iterator& l, const iterator& r) noexcept(see below)
requires [indirectly_swappable](alg.req.ind.swap#concept:indirectly_swappable "24.3.7.4 Concept indirectly_­swappable [alg.req.ind.swap]")<iterator_t<Base>>;
`
[33](#iterator-33)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13104)
*Preconditions*: None of the iterators in l.*current_* is equal to
an iterator in r.*current_*[.](#iterator-33.sentence-1)
[34](#iterator-34)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13109)
*Effects*: For every integer 0≤i<N,
performsranges​::​iter_swap(l.*current_*[i], r.*current_*[i])[.](#iterator-34.sentence-1)
[35](#iterator-35)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13115)
*Remarks*: The exception specification is equivalent to:noexcept(ranges::iter_swap(declval<iterator_t<*Base*>>(), declval<iterator_t<*Base*>>()))
#### [25.7.27.4](#sentinel) Class template adjacent_view​::​*sentinel* [[range.adjacent.sentinel]](range.adjacent.sentinel)
[🔗](#lib:adjacent_view::sentinel)
namespace std::ranges {template<[forward_range](range.refinements#concept:forward_range "25.4.6 Other range refinements [range.refinements]") V, size_t N>requires [view](range.view#concept:view "25.4.5 Views [range.view]")<V> && (N > 0)template<bool Const>class adjacent_view<V, N>::*sentinel* {using *Base* = *maybe-const*<Const, V>; // *exposition only* sentinel_t<*Base*> *end_* = sentinel_t<*Base*>(); // *exposition only*constexpr explicit *sentinel*(sentinel_t<*Base*> end); // *exposition only*public:*sentinel*() = default; constexpr *sentinel*(*sentinel*<!Const> i)requires Const && [convertible_to](concept.convertible#concept:convertible_to "18.4.4 Concept convertible_­to [concept.convertible]")<sentinel_t<V>, sentinel_t<*Base*>>; template<bool OtherConst>requires [sentinel_for](iterator.concept.sentinel#concept:sentinel_for "24.3.4.7 Concept sentinel_­for [iterator.concept.sentinel]")<sentinel_t<*Base*>, iterator_t<*maybe-const*<OtherConst, V>>>friend constexpr bool operator==(const *iterator*<OtherConst>& x, const *sentinel*& y); template<bool OtherConst>requires [sized_sentinel_for](iterator.concept.sizedsentinel#concept:sized_sentinel_for "24.3.4.8 Concept sized_­sentinel_­for [iterator.concept.sizedsentinel]")<sentinel_t<*Base*>, iterator_t<*maybe-const*<OtherConst, V>>>friend constexpr range_difference_t<*maybe-const*<OtherConst, V>>operator-(const *iterator*<OtherConst>& x, const *sentinel*& y); template<bool OtherConst>requires [sized_sentinel_for](iterator.concept.sizedsentinel#concept:sized_sentinel_for "24.3.4.8 Concept sized_­sentinel_­for [iterator.concept.sizedsentinel]")<sentinel_t<*Base*>, iterator_t<*maybe-const*<OtherConst, V>>>friend constexpr range_difference_t<*maybe-const*<OtherConst, V>>operator-(const *sentinel*& y, const *iterator*<OtherConst>& x); };}
[🔗](#lib:adjacent_view::sentinel,constructor)
`constexpr explicit sentinel(sentinel_t<Base> end);
`
[1](#sentinel-1)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13164)
*Effects*: Initializes *end_* with end[.](#sentinel-1.sentence-1)
[🔗](#lib:adjacent_view::sentinel,constructor_)
`constexpr sentinel(sentinel<!Const> i)
requires Const && [convertible_to](concept.convertible#concept:convertible_to "18.4.4 Concept convertible_­to [concept.convertible]")<sentinel_t<V>, sentinel_t<Base>>;
`
[2](#sentinel-2)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13176)
*Effects*: Initializes *end_* with std​::​move(i.*end_*)[.](#sentinel-2.sentence-1)
[🔗](#lib:operator==,adjacent_view::sentinel)
`template<bool OtherConst>
requires [sentinel_for](iterator.concept.sentinel#concept:sentinel_for "24.3.4.7 Concept sentinel_­for [iterator.concept.sentinel]")<sentinel_t<Base>, iterator_t<maybe-const<OtherConst, V>>>
friend constexpr bool operator==(const iterator<OtherConst>& x, const sentinel& y);
`
[3](#sentinel-3)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13189)
*Effects*: Equivalent to: return x.*current_*.back() == y.*end_*;
[🔗](#lib:operator-,adjacent_view::sentinel)
`template<bool OtherConst>
requires [sized_sentinel_for](iterator.concept.sizedsentinel#concept:sized_sentinel_for "24.3.4.8 Concept sized_­sentinel_­for [iterator.concept.sizedsentinel]")<sentinel_t<Base>, iterator_t<maybe-const<OtherConst, V>>>
friend constexpr range_difference_t<maybe-const<OtherConst, V>>
operator-(const iterator<OtherConst>& x, const sentinel& y);
`
[4](#sentinel-4)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13203)
*Effects*: Equivalent to: return x.*current_*.back() - y.*end_*;
[🔗](#lib:operator-,adjacent_view::sentinel_)
`template<bool OtherConst>
requires [sized_sentinel_for](iterator.concept.sizedsentinel#concept:sized_sentinel_for "24.3.4.8 Concept sized_­sentinel_­for [iterator.concept.sizedsentinel]")<sentinel_t<Base>, iterator_t<maybe-const<OtherConst, V>>>
friend constexpr range_difference_t<maybe-const<OtherConst, V>>
operator-(const sentinel& y, const iterator<OtherConst>& x);
`
[5](#sentinel-5)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/ranges.tex#L13217)
*Effects*: Equivalent to: return y.*end_* - x.*current_*.back();
Reference in New Issue View Git Blame Copy Permalink