std::basic_string<CharT,Traits,Allocator>::swap

`void swap( basic_string& other );`		(C++17)
`void swap( basic_string& other ) noexcept(/* see below */);`		(C++17) (C++20)
`constexpr void swap( basic_string& other ) noexcept(/* see below */);`		(C++20)

other

Allocator swap *this other

(C++11)

other

-

()

noexcept :

noexcept(std::allocator_traits<Allocator>::propagate_on_container_swap::value || std::allocator_traits<Allocator>::is_always_equal::value)

(C++17)

Run this code

#include <string>
#include <iostream>

int main() 
{
    std::string a = "AAA";
    std::string b = "BBB";

    std::cout << "before swap" << '\n';
    std::cout << "a: " << a << '\n';
    std::cout << "b: " << b << '\n';

    a.swap(b);

    std::cout << "after swap" << '\n';
    std::cout << "a: " << a << '\n';
    std::cout << "b: " << b << '\n';
}

:

before swap
a: AAA
b: BBB
after swap
a: BBB
b: AAA

cppreference.com

std::basic_string<CharT,Traits,Allocator>::swap