std::swap(std::flat_map)

 

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std::flat_map

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Member functions

flat_map::flat_map flat_map::operator= Element access flat_map::at flat_map::operator[] Iterators flat_map::beginflat_map::cbegin flat_map::endflat_map::cend flat_map::rbeginflat_map::crbegin flat_map::rendflat_map::crend Lookup flat_map::count flat_map::find flat_map::contains flat_map::equal_range    flat_map::lower_bound flat_map::upper_bound Capacity flat_map::size flat_map::max_size flat_map::empty Modifiers flat_map::clear flat_map::erase flat_map::swap flat_map::emplace flat_map::extract flat_map::replace flat_map::insert flat_map::insert_range flat_map::insert_or_assign flat_map::emplace_hint flat_map::try_emplace Observers flat_map::key_comp flat_map::keys flat_map::value_comp flat_map::values

Non-member functions

operator==operator<=>         swap(std::flat_map) erase_if(std::flat_map)

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uses_allocator<std::flat_map>

Tags

sorted_unique       sorted_unique_t

Deduction guides

 

Defined in header <flat_map>
friend void swap( std::flat_map& lhs, std::flat_map& rhs ) noexcept;		(since C++23)

Specializes the std::swap algorithm for std::flat_map. Swaps the contents of lhs and rhs. Calls lhs.swap(rhs).

Parameters

lhs, rhs

-

containers whose contents to swap

Return value

(none)

Complexity

Same as swapping the underlying containers.

Example

Run this code

#include <algorithm>
#include <iostream>
#include <flat_map>
 
int main()
{
    std::flat_map<int, char> alice{{1, 'a'}, {2, 'b'}, {3, 'c'}};
    std::flat_map<int, char> bob{{7, 'Z'}, {8, 'Y'}, {9, 'X'}, {10, 'W'}};
 
    auto print = [](std::pair<const int, char>& n)
    {
        std::cout << ' ' << n.first << ':' << n.second;
    };
 
    // Print state before swap
    std::cout << "Alice:";
    std::for_each(alice.begin(), alice.end(), print);
    std::cout << "\nBobby:";
    std::for_each(bob.begin(), bob.end(), print);
    std::cout << '\n';
 
    std::cout << "-- SWAP\n";
    std::swap(alice, bob);
 
    // Print state after swap
    std::cout << "Alice:";
    std::for_each(alice.begin(), alice.end(), print);
    std::cout << "\nBobby:";
    std::for_each(bob.begin(), bob.end(), print);
    std::cout << '\n';
}

Output:

Alice: 1:a 2:b 3:c
Bobby: 7:Z 8:Y 9:X 10:W
-- SWAP
Alice: 7:Z 8:Y 9:X 10:W
Bobby: 1:a 2:b 3:c

See also

swap	swaps the contents (public member function)