public member function
<queue>

std::queue::swap

void swap (queue& x) noexcept(/*see below*/);
Swap contents
Exchanges the contents of the container adaptor (*this) by those of x.

This member function calls the non-member function swap (unqualified) to swap the underlying containers.

The noexcept specifier matches the swap operation on the underlying container.

Parameters

x
Another queue container adaptor of the same type (i.e., instantiated with the same template parameters, T and Container). Sizes may differ.

Return value

none

Example

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// queue::swap
#include <iostream>       // std::cout
#include <queue>          // std::queue

int main ()
{
  std::queue<int> foo,bar;
  foo.push (10); foo.push(20); foo.push(30);
  bar.push (111); bar.push(222);

  foo.swap(bar);

  std::cout << "size of foo: " << foo.size() << '\n';
  std::cout << "size of bar: " << bar.size() << '\n';

  return 0;
}

Output:

size of foo: 2
size of bar: 3


Complexity

Constant.

Data races

Both *this and x are modified.

Exception safety

Provides the same level of guarantees as the operation performed on the underlying container objects.

See also