_EXPORT_STD template <class _Mutex>
class _NODISCARD_LOCK lock_guard { // class with destructor that unlocks a mutex
public:
    using mutex_type = _Mutex;

    explicit lock_guard(_Mutex& _Mtx) : _MyMutex(_Mtx) { // construct and lock
        _MyMutex.lock();
    }

    lock_guard(_Mutex& _Mtx, adopt_lock_t) noexcept // strengthened
        : _MyMutex(_Mtx) {} // construct but don't lock

    ~lock_guard() noexcept {
        _MyMutex.unlock();
    }

    lock_guard(const lock_guard&)            = delete;
    lock_guard& operator=(const lock_guard&) = delete;

private:
    _Mutex& _MyMutex;
};