std::swap(std::pair)

Defined in header <utility> 
template< class T1, class T2 >
void swap( pair<T1,T2>& x, pair<T1,T2>& y ) noexcept(/* see below */);
 (since C++11)
(until C++20) 
template< class T1, class T2 >
constexpr void swap( pair<T1,T2>& x, pair<T1,T2>& y ) noexcept(/* see below */);
 (since C++20)

Swaps the contents of x and y. Equivalent to x.swap(y).

This function does not participate in overload resolution unless std::is_swappable_v<first_type> && std::is_swappable_v<second_type> is true.

 (since C++17)

Parameters

x, y - pairs whose contents to swap

Return value

(none).

Exceptions

noexcept specification:
noexcept(noexcept(x.swap(y)))

See also

swaps the values of two objects
(function template)

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