NAME¶

std::flat_set::extract - std::flat_set::extract

Synopsis¶

container_type extract() &&; (since C++23)

Extracts adapted container c. Equivalent to return std::move(c);.

After this operation *this is empty, even if an exception is thrown.

Parameters¶

(none)

Return value¶

std::move(c).

Complexity¶

Constant.

Example¶

// Run this code

#include <cassert>
#include <flat_set>
#include <print>
#include <type_traits>
#include <vector>

int main()
{
std::flat_set<int> set{1, 2, 3};
const auto size = set.size();

auto c = set.extract();
assert(c.size() == size);
assert(set.empty());
assert(set.keys().empty());
assert(set.values().empty());

// The default keys container is std::vector:
static_assert(std::is_same_v<decltype(c), std::vector<int>>);

std::println("{}", c);
}

Output:¶

[1, 2, 3]

See also¶

replace replaces the underlying container
(public member function)