Question

I have a template class, called Cell, here the definition:

template <class T>
class OneCell
{
.....
}

I have a cast operator from Cell to T, here

virtual operator const T() const
{
   .....
}

Now i have derived class, called DCell, here

template <class T>
class DCell : public Cell<T>
{
.....
}

I need to override the Cell’s cast operator (insert a little if), but after I need to call the Cell’s cast operator. In other methods it’s should be something like

virtual operator const T() const
{
    if (...)
    {
        return Cell<T>::operator const T;
    }
    else throw ...
}

but i got a compiler error

error: argument of type ‘const int (Cell::)()const’ does not match ‘const int’

What can I do?

Thank you, and sorry about my poor English.

Answer 1

You’re not actually calling the operator:

return Cell<T>::operator const T();

Full code:

template <class T>
class OneCell
{
public:
    virtual operator const T() const
{
        return T();
    }
};

template <class T>
class DCell : public OneCell<T>
{
public:
    virtual operator const T() const
    {
        cout << "operator called";
        return OneCell<T>::operator const T();
    }
};

int _tmain(int argc, _TCHAR* argv[])
{
    DCell<int> x;
    int y = (int)x;
}