std::unique_ptr<T,Deleter>::swap

void swap( unique_ptr& other ) noexcept;

Swaps the managed objects and associated deleters of *this and another unique_ptr object other.

Parameters

other - another unique_ptr object to swap the managed object and the deleter with

Return value

(none)

Example

#include <iostream>
#include <memory>
 
struct Foo {
    Foo(int _val) : val(_val) { std::cout << "Foo...\n"; }
    ~Foo() { std::cout << "~Foo...\n"; }
    int val;
};
 
int main()
{
    std::unique_ptr<Foo> up1(new Foo(1));
    std::unique_ptr<Foo> up2(new Foo(2));
 
    up1.swap(up2);
 
    std::cout 
        << "up1->val:" 
        << up1->val << '\n';
    std::cout 
        << "up2->val:" 
        << up2->val << '\n';
}

Result

Foo...
Foo...
up1->val:2
up2->val:1
~Foo...
~Foo...