Method extract

include/hipSYCL/common/unordered_dense.hpp:1413–1415

nonstandard API: *this is emptied. Also see "A Standard flat_map" https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/p0429r9.pdf

    // nonstandard API: *this is emptied.
    // Also see "A Standard flat_map" https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/p0429r9.pdf
    auto extract() && -> value_container_type {
        return std::move(m_values);
    }

    // nonstandard API:
    // Discards the internally held container and replaces it with the one passed. Erases non-unique elements.