std::ranges::adjacent_view<V,N>:: iterator <Const>:: operator++,--,+=,-=

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C++
Ranges library
Range adaptors
std::ranges::adjacent_view
Member functions
Iterator
Member functions
adjacent_view:: iterator ::operator++
adjacent_view:: iterator ::operator++ (int)
adjacent_view:: iterator ::operator--
adjacent_view:: iterator ::operator-- (int)
adjacent_view:: iterator ::operator+=
adjacent_view:: iterator ::operator-=
Non-member functions
Sentinel
Member functions
Non-member functions
constexpr /*iterator*/ & operator ++ ( ) ;
(1) (since C++23)
constexpr /*iterator*/ operator ++ ( int ) ;
(2) (since C++23)
constexpr /*iterator*/ & operator -- ( )
requires ranges:: bidirectional_range < Base > ;
(3) (since C++23)
constexpr /*iterator*/ operator -- ( int )
requires ranges:: bidirectional_range < Base > ;
(4) (since C++23)
constexpr /*iterator*/ & operator + = ( difference_type n )
requires ranges:: random_access_range < Base > ;
(5) (since C++23)
constexpr /*iterator*/ & operator - = ( difference_type n )
requires ranges:: random_access_range < Base > ;
(6) (since C++23)

Increments or decrements the iterator.

Let current_ be an underlying array of iterators.

1) Equivalent to: 
for (auto& i : current_)
    i = std::ranges::next(i);
return *this;
The behavior is undefined if before the call the current_. back ( ) is not incrementable.
2) Equivalent to: 
auto tmp = *this;
++*this;
return tmp;
3) Equivalent to: 
for (auto& i : current_)
    i = std::ranges::prev(i);
return *this;
The behavior is undefined if before the call the current_. front ( ) is not decrementable.
4) Equivalent to: 
auto tmp = *this;
--*this;
return tmp;
5) Equivalent to: 
for (auto& i : current_)
    i = i + n;
return *this;
The behavior is undefined if before the call the current_. back ( ) + n does not have well-defined behavior.
6) Equivalent to: 
for (auto& i : current_)
    i = i - n;
return *this;
The behavior is undefined if before the call the current_. front ( ) - n does not have well-defined behavior.

Parameters

n - position relative to current location

Return value

1,3,5,6) * this
2,4) A copy of * this that was made before the change.

Example

Run this code 
#include <cassert>
#include <list>
#include <ranges>
#include <utility>
#include <vector>
 
int main()
{
    {
        auto v = std::vector{0, 1, 2, 3, 4, 5};
        auto i = (v | std::views::pairwise).begin();
        assert((*i == std::pair{0, 1}));
        ++i;                            // overload (1)
        assert((*i == std::pair{1, 2}));
        --i;                            // overload (3)
        assert((*i == std::pair{0, 1}));
        i += 2;                         // overload (5)
        assert((*i == std::pair{2, 3}));
        i -= 2;                         // overload (6)
        assert((*i == std::pair{0, 1}));
    }
    {
        auto v = std::list{0, 1, 2, 3, 4, 5};
        auto i = (v | std::views::pairwise).begin();
        assert((*i == std::pair{0, 1}));
        ++i;                            // overload (1)
        assert((*i == std::pair{1, 2}));
        --i;                            // overload (3)
        assert((*i == std::pair{0, 1}));
//      i += 2; // Error: v is not a random_access_range; overload (5)
//      i -= 2; // Error: v is not a random_access_range; overload (6)
    }
}

See also

(C++23)
performs iterator arithmetic
(public member function)
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