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#include <stdio.h>
#include <iostream>
#include <functional>
#include <vector>
using namespace std;
class IEvent
{
    
public:
    int m_EventType;
    virtual ~IEvent() {}
};

template<class...Args>
class Event : public IEvent {};

template<int eventType,class...Args>
class Event<int, bool(Args...)> : public IEvent
{
public:
    Event(bool(*func)(Args...)) :m_FnPtr(func)
    { 
         m_EventType = eventType;
         m_ListenersList.push_back(m_FnPtr);
    }

template <typename T>
    Event(T* obj, bool(T::* Func)(Args...))
    {
        m_EventType = eventType;
        m_FnPtr = [obj, Func](Args&&... args)->bool {
            return (obj->*Func)(std::forward<Args>(args)...);
        };
        
        m_ListenersList.push_back(m_FnPtr);
    }

void NotifyListeners(Args&&...args) const
    {
        for (auto& itr : m_ListenersList)
        {
            (itr)(std::forward<Args>(args)...);
        }
        
    }
private:
    std::function<bool(Args...)> m_FnPtr;
    std::vector<std::function<bool(Args...)>> m_ListenersList; 
};

class GuiWindow
{
public:
    bool OnKeyUp(bool, double)
    {
        cout << endl << "Member Function called";
        return true;
    }

bool OnClicked()
    {
        cout << endl << "OnClicked";
        return true;
    }
    
    //using KeyupListenerType = Event<"KeyUp", bool(bool, double)>;
};

int main()
{
    GuiWindow w;
    Event<90,bool(bool, double)> evnt(&w, &GuiWindow::OnKeyUp);
    evnt.NotifyListeners(true, 6.8);
    return 0;
}

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