How to define a member function of a class.? Solution class B { public: virtual

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class B { public: virtual void vf(); void mf(); virtual void mf(int); ... }; class D: public B { public: virtual void vf(); // overrides B::vf void mf(); // hides B::mf; see Item33 ... }; D x; // x is an object of type D B *pB = &x; // get pointer to x D *pD = &x; // get pointer to x pD->vf(); // calls D::mf, as expected pB->vf(); // calls D::mf, as expected pD->mf(); // calls D::mf, as expected pB->mf(); // calls B::mf - surprise! pD->mf(1); // error - D::mf() hides B::mf(int)! pB->mf(1); // calls B::mf(int) So this is not exactly how final behaves in Java, but you can only get this close with C++. An alternative might be to prevent subclassing altogether. The technical - working, but not nice - solution to this is to declare all your constructors private (and provide a static factory method if you want to allow instantiation of your class, of course).

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