std::iter_swap(std::reverse_iterator)

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std::reverse_iterator

Member functions
reverse_iterator::reverse_iterator
reverse_iterator::operator=
reverse_iterator::base
reverse_iterator::operator*reverse_iterator::operator->
reverse_iterator::operator[]
reverse_iterator::operator++reverse_iterator::operator+reverse_iterator::operator+=reverse_iterator::operator--reverse_iterator::operator-reverse_iterator::operator-=
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operator+
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iter_move (C++20)
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make_reverse_iterator (C++14)

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template<std::indirectly_swappable<Iter> Iter2> friendconstexprvoid iter_swap(const reverse_iterator& x, conststd::reverse_iterator<Iter2>& y) noexcept(/* see below */);		(since C++20)

Swaps the objects pointed to by two adjusted underlying iterators.

Equivalent toauto tmp_x= x.base();
auto tmp_y= y.base();
ranges::iter_swap(--tmp_x,--tmp_y);.

This function template is not visible to ordinaryunqualified orqualified lookup, and can only be found byargument-dependent lookup whenstd::reverse_iterator<Iter> is an associated class of the arguments.

[edit]Parameters

x, y

reverse iterators to the elements to swap

[edit]Complexity

Constant.

[edit]Exceptions

noexcept specification:

noexcept(

std::is_nothrow_copy_constructible_v<Iter>&&
std::is_nothrow_copy_constructible_v<Iter2>&&
noexcept(ranges::iter_swap(--std::declval<Iter&>(),--std::declval<Iter2&>()))

)

[edit]Example

Run this code

#include <iostream>#include <iterator>#include <list>#include <vector> int main(){std::vector v{1,2,3};std::list l{4,5,6}; std::reverse_iterator<std::vector<int>::iterator> r1{v.rbegin()};std::reverse_iterator<std::list<int>::iterator> r2{l.rbegin()}; std::cout<<*r1<<' '<<*r2<<'\n';     iter_swap(r1, r2);// ADL std::cout<<*r1<<' '<<*r2<<'\n';}

Output:

3 66 3

[edit]See also

swap	swaps the values of two objects (function template)[edit]
swap_ranges	swaps two ranges of elements (function template)[edit]
iter_swap	swaps the elements pointed to by two iterators (function template)[edit]
iter_swap (C++20)	swaps the values referenced by two dereferenceable objects (customization point object)[edit]
iter_swap (C++20)	swaps the objects pointed to by two underlying iterators (function template)[edit]