Question

Imagine I have two class A and B defined like this :

class A {
public:
    virtual void pureVirtual() = 0;
}

class B : public A {
public: 
    virtual void pureVirtual();
}

I have of course other methods, but that’s just for the example. Now, in my cpp code I have this kind of var :

B *myB = new B;
A *myA = myB;

Is it possible to delete myB object by calling delete on myA like this : delete myA; ? Do I have to do something special to be able to do that ?
Is it okay with OOP ideas and programming style, or a very bad idea ?

Thank you!

Answer 1

It is possible, but A needs a virtual destructor for this to work correctly:

class A {
public:
    virtual void pureVirtual() = 0;
    virtual ~A() {}
}

From an OO-perspective there is nothing wrong with this.