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iter_swap(std::move_iterator)

template< std::indirectly_swappable<Iter> Iter2 >
  friend constexpr void
    iter_swap( const move_iterator& x, const std::move_iterator<Iter2>& y )
      noexcept(/*see below*/);
(since C++20)

Swaps the objects pointed to by two underlying iterators. The function body is equivalent to ranges::iter_swap(x.base(), y.base());.

This function template is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::move_iterator<Iter> is an associated class of the arguments.

Parameters

x, y - move iterators to the elements to swap.

Return value

(none).

Complexity

Constant.

Exceptions

noexcept specification:
noexcept(noexcept( ranges::iter_swap( x.base(), y.base() ) ))

Example

#include <iostream>
#include <iterator>
#include <string>
#include <vector>
 
int main()
{
    std::vector<std::string> p { "AA", "EE" },
                             q { "ⱯⱯ", "ƎƎ" };
 
    std::move_iterator<std::vector<std::string>::iterator>
        x = std::make_move_iterator( p.begin() ),
        y = std::make_move_iterator( q.begin() );
 
    std::cout << *x << ' ' << *y << '\n';
 
    iter_swap(x, y); // ADL
 
    std::cout << *x << ' ' << *y << '\n';
}

Output:

AA ⱯⱯ
ⱯⱯ AA

See also

swaps the values of two objects
(function template)
swaps two ranges of elements
(function template)
swaps the elements pointed to by two iterators
(function template)
(C++20)
swaps the values referenced by two dereferenceable objects
(customization point object)
(C++20)
swaps the objects pointed to by two adjusted underlying iterators
(function template)

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