Question

I have three classes that inherit from both whirlyB and gameCreature. I am using all three sub classes in a collection of gameCreatures. Is there a way to use the inherited functionality from whirlyB. I am only given the choice of using gameCreature functions. What should I do to get the functionality of whirlyB?

Answer 1

Here’s a silly idea, for the case where you’re stuck with one of the base pointers but are free to modify the classes. Suppose we have:

struct InBetween : Rock, HardPlace { /* ...  */ }

and suppose that you only have Rock-pointers available. Edit Rock as follows:

struct Rock
{
    virtual HardPlace * get_other() const = 0;
    // ...
};

Now add to each derived class the following:

struct InBetween : Rock, HardPlace
{
    virtual HardPlace * get_other() const { return this; }
    // ...
};

Now, given Rock * r, you can say HardPlace * h = r->get_other().

I wouldn’t really call this good design, or even recommendable, but I think that’s a literal answer to your question.