Re: class that have a member of type that's derived from it.

As others mentioned, watch for "recursion" on
containment (you can't have an object that
contains itself which contains itself which
contains itself, ...ad infinitum )

But, if you're talking about some "utility"
class of derived type (perhaps it has no state,
or perhaps a static will do), you can try
something like:

<code>
struct Derived;
struct Base {
  public:
    virtual const Derived& getDerived(void) const = 0;
    void someFunc(void) {
      // ...call "getDerived()" all you want in here.
    }
};
struct Derived : public Base {
  static const Derived MY_INSTANCE_;
  public:
    virtual const Derived& getDerived(void) const {
      return MY_INSTANCE_;
    }
};
</code>
:%s/struct/class/g

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