iter_swap(std::counted_iterator)

Since C++20

Swaps the objects pointed to by two underlying iterators. The behavior is undefined if either x.count() or y.count() is equal to 0.

# Declarations

template< std::indirectly_swappable<I> I2 >
friend constexpr void
iter_swap( const counted_iterator& x, const std::counted_iterator<I2>& y )
noexcept(noexcept(ranges::iter_swap(x.base(), y.base())));

(since C++20)

# Parameters

# Return value

(none)

# Example

#include <iostream>
#include <iterator>
#include <list>
#include <vector>
 
int main()
{
    std::vector p{1, 2, 3, 4},
                q{5, 6, 7, 8};
 
    std::counted_iterator<std::vector<int>::iterator> ip{p.begin(), 2};
    std::counted_iterator<std::vector<int>::iterator> iq{q.begin(), 3};
 
    std::cout << *ip << ' ' << *iq << '\n';
    iter_swap(ip, iq); // ADL
    std::cout << *ip << ' ' << *iq << '\n';
 
    std::list x{0, 1, 3};
    std::counted_iterator<std::list<int>::iterator> ix{x.begin(), 2};
//  iter_swap(ip, ix); // error: not indirectly swappable
}

# See also