std::iter_swap(std::reverse_iterator)
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 < cpp | iterator | reverse iterator 
 
 
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Iterator library 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
  
 
 
 
 
 
  
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  std::reverse_iterator 
 
 
 
(C++20)
iter_swap
(C++20)
(C++14)
template< std::indirectly_swappable <Iter> Iter2 >
 
 (since C++20) 
friend constexpr void iter_swap( const reverse_iterator& x,
                                 const std::reverse_iterator <Iter2>& y )
Swaps the objects pointed to by two adjusted underlying iterators.
Equivalent to auto tmp_x = x.base();
auto tmp_y = y.base();
ranges::iter_swap (--tmp_x, --tmp_y);.
This function template is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::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 6 6 3
[edit] See also
(C++20)
(customization point object)[edit]