std::flat_map<Key,T,Compare,KeyContainer,MappedContainer>::keys
const key_container_type& keys() const noexcept; | (since C++23) |
Return a constant reference to the adapted keys container. Equivalent to return c.keys;.
Return value
The underlying keys container.
Complexity
Constant.
Example
#include <flat_map>
#include <print>
#include <type_traits>
#include <vector>
int main()
{
std::flat_map<int, double> adaptor{{1, 1.1}, {2, 2.2}, {3, 3.3}};
// The default keys container is std::vector:
static_assert(std::is_same_v<decltype(adaptor.keys()), const std::vector<int>&>);
std::println("{}", adaptor.keys());
}
Output:
[1, 2, 3]
See also
| direct access to the underlying values container (public member function) |
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