C++ lambda as parameter with variable arguments

I want to create an event system that uses lambda functions as its subscribers/listeners, and an event type to assign them to the specific event that they should subscribe to. The lambdas should have variable arguments, as different kinds of events use different kinds of arguments/provide the subscribers with different kinds of data.

For my dispatcher, I have the following:

class EventDispatcher {
public:
    static void subscribe(EventType event_type, std::function<void(...)> callback);
    void queue_event(Event event);
    void dispatch_queue();

private:
    std::queue<Event*> event_queue;
    std::map<EventType, std::function<void(...)>> event_subscribers;
};

No issues here, but when I go to implement the subscribe() function in my .cpp file, like this:

void EventDispatcher::subscribe(EventType event_type, std::function<void(...)> callback) {
    ... (nothing here yet)
}

The IDE shows me this:

Implicit instantiation of undefined template 'std::function<void (...)>'

Solution

After the input from @joergbrech and @HolyBlackCat I made this

enum class EventType {
    WindowClosed, WindowResized, WindowFocused, WindowLostFocus, WindowMoved,
    AppTick, AppUpdate, AppRender,
    KeyPressed, KeyRelease,
    MouseButtonPressed, MouseButtonRelease, MouseMoved, MouseScrolled,
    ControllerAxisChange, ControllerButtonPressed, ControllerConnected, ControllerDisconnected
};

class IEvent {
public:
    IEvent(EventType event_type) {
        this->event_type = event_type;
    }

    EventType get_event_type() {
        return event_type;
    }

private:
    EventType event_type;
};

class IEventSubscriber {
public:
    /**
     * @param event The event that is passed to the subscriber by the publisher; should be cast to specific event
     * */
    virtual void on_event(IEvent *event) = 0;

    EventType get_event_type() {
        return event_type;
    }

protected:
    explicit IEventSubscriber(EventType event_type) {
        this->event_type = event_type;
    }

private:
    EventType event_type;
};

class FORGE_API EventPublisher {
public:
    static void subscribe(IEventSubscriber *subscriber);
    static void queue_event(IEvent *event);
    static void dispatch_queue();

private:
    static std::queue<IEvent*> event_queue;
    static std::set<IEventSubscriber*> event_subscribers;
};

I've tested it and I get the expected result from this solution. For the full code solution -> https://github.com/F4LS3/forge-engine