My gui application supports polymorphic timed events so that means that the user calls new, and the gui calls delete. This can create a problem if the runtimes are incompatible.

So I was told a proposed solution would be this:

class base;

class Deallocator {
    void operator()(base* ptr) 
    {
        delete ptr;
    }
}

class base {
public:
base(Deallocator dealloc) 
{
    m_deleteFunc = dealloc;
}
~base() 
{
    m_deleteFunc(this);
}

private:
Deallocator m_deleteFunc;
}

int main
{
    Deallocator deletefunc;

    base baseObj(deletefunc);
}

While this is a good solution, it does demand that the user create a Deallocator object which I do not want. I was however wondering if I provided a Deallocator to each derived class: eg

class derived : public base
{
  Deallocator dealloc;
public:
  Derived() : base(dealloc);
{
}
};

I think this still does not work though. The constraint is that: The addTimedEvent() function is part of the Widget class which is also in the dll, but it is instanced by the user. The other constraint is that some classes which derive from Widget call this function with their own timed event classes.

Given that "he who called new must call delete" what could work given these constraints?

Thanks