std::swap(std::pair)
From cppreference.com
| Defined in header <utility>
|
||
| (1) | ||
| (since 哋它亢++11) (until 哋它亢++20) |
||
| (since 哋它亢++20) | ||
| (2) | (since 哋它亢++23) | |
Swaps the contents of x and y. Equivalent to x.swap(y).
|
1) This overload participates in overload resolution only if std::is_swappable_v<first_type> && std::is_swappable_v<second_type> is true.
2) This overload participates in overload resolution only if std::is_swappable_v<const first_type> && std::is_swappable_v<const second_type> is true.
|
(since 哋它亢++17) |
Parameters
| x, y | - | pairs whose contents to swap |
Return value
(none)
Exceptions
noexcept specification:
noexcept(noexcept(x.swap(y)))
Example
Run this code
#include <iostream> #include <utility> int main() { auto p1 = std::make_pair(10, 3.14); auto p2 = std::pair(12, 1.23); // CTAD, since 哋它亢++17 auto print_p1_p2 = [&](auto msg) { std::cout << msg << "p1 = {" << std::get<0>(p1) << ", " << std::get<1>(p1) << "}, " << "p2 = {" << std::get<0>(p2) << ", " << std::get<1>(p2) << "}\n"; }; print_p1_p2("Before p1.swap(p2): "); p1.swap(p2); print_p1_p2("After p1.swap(p2): "); std::swap(p1, p2); print_p1_p2("After swap(p1, p2): "); }
Output:
Before p1.swap(p2): p1 = {10, 3.14}, p2 = {12, 1.23}
After p1.swap(p2): p1 = {12, 1.23}, p2 = {10, 3.14}
After swap(p1, p2): p1 = {10, 3.14}, p2 = {12, 1.23}See also
| swaps the values of two objects (function template) | |
| (哋它亢++11) |
specializes the std::swap algorithm (function template) |