std::ranges::adjacent_view<V,N>::iterator
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                    < cpp | ranges | adjacent view
                    
                                                            
                    |   template< bool Const > class /*iterator*/  | 
 (since C++23)  (exposition only*)  | 
|
The return type of adjacent_view::begin, and of adjacent_view::end when the underlying view V is a common_range.
The type /*iterator*/<true> is returned by the const-qualified overloads. The type /*iterator*/<false> is returned by the non-const-qualified overloads.
Member types
| Member type | Definition | 
 Base (private)
 | 
 const V if Const is true, otherwise V. (exposition-only member type*)  | 
 iterator_category
 | 
std::input_iterator_tag | 
 iterator_concept
 | 
  | 
 value_type
 | 
std::tuple</*REPEAT*/(ranges::range_value_t<Base>, N)...>; | 
 difference_type
 | 
ranges::range_difference_t<Base> | 
Data members
| Member object | Definition | 
  current_ (private)
 | 
 std::array<ranges::iterator_t<Base>, N>. (exposition-only member object*)  | 
Member functions
|   constructs an iterator  (public member function)  | |
|   accesses the element  (public member function)  | |
|   accesses an element by index  (public member function)  | |
|   advances or decrements the underlying iterators  (public member function)  | 
Non-member functions
|   compares the underlying iterators  (function)  | |
|    (C++23)  | 
  performs iterator arithmetic  (function)  | 
|    (C++23)  | 
  casts the result of dereferencing the underlying iterator to its associated rvalue reference type  (function)  | 
|    (C++23)  | 
  swaps the objects pointed to by two underlying iterators  (function)  | 
Example
Run this code
#include <cassert> #include <concepts> #include <list> #include <ranges> #include <tuple> #include <utility> #include <vector> int main() { auto v = std::vector{0, 1, 2, 3, 4, 5}; auto i = (v | std::views::adjacent<3>).begin(); using I = decltype(i); static_assert(std::same_as<I::value_type, std::tuple<int, int, int>>); static_assert(std::same_as<I::iterator_concept, std::random_access_iterator_tag>); // some of available operators: ++i; i++; --i; i--; i += 2; i -= 2; assert(i[2] == std::tuple(2, 3, 4)); using DI = decltype(*i); static_assert(std::same_as<DI, std::tuple<int&, int&, int&>>); std::get<1>(*i) = 42; // modifies v[1] via iterator i assert(v[1] == 42); auto l = std::list{0, 1, 2, 3, 4, 5}; auto j = (l | std::views::adjacent<3>).begin(); using J = decltype(j); static_assert(std::same_as<J::value_type, std::tuple<int, int, int>>); static_assert(std::same_as<J::iterator_concept, std::bidirectional_iterator_tag>); ++j; --j; j++; j--; // some of available operators // j += 2; j -= 2; // error: these operator are not available // std::ignore() = j[1]; // for bidirectional iterator }
References
- C++23 standard (ISO/IEC 14882:2024):
 
- 26.7.25.3 Class template adjacent_view::iterator [range.adjacent.iterator]