std::any::swap

 

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std::any

Member functions

any::any

any::~any

any::operator=

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any::emplace

any::reset

any::swap

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any::has_value

any::type

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swap(std::any)

any_cast

make_any

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bad_any_cast

 

void swap( any& other ) noexcept;		(since C++17)

Swaps the content of two any objects.

Parameters

other

-

object to swap with

Example

Run this code

#include <any>
#include <print>
#include <string>
#include <string_view>
 
int main()
{
    std::any a = std::string{"King"};
    std::any b = std::string_view{"Queen"};
    std::println("a = {}", std::any_cast<std::string&>(a));
    std::println("b = {}", std::any_cast<std::string_view&>(b));
    std::println("swap(a, b)");
    a.swap(b);
    std::println("a = {}", std::any_cast<std::string_view&>(a));
    std::println("b = {}", std::any_cast<std::string&>(b));
}

Output:

a = King
b = Queen
swap(a, b)
a = Queen
b = King