Question

I have following problem:

• want to inherit some class as protected (outside derived class i dont need any member or function from base class)
• want to be able to access base constructor in some way

Here is an example (compile error):

class Animal
{
public:
    explicit Animal(void){;}
};

class Dog: private Animal
{
public:
    explicit Dog(void){;}
};

int main(int argc, char *argv[])
{
    Dog* pDog1 = new Dog();

    Animal* pDog2 = new Dog();

    return 0;
}

How can I solve this?
Thanks!

edit: Let’s say that Base class is inherited from some library thus i cant change it.

Answer 1

As an alternative to reinterpret_cast, you may expose the base class with a method. If one day you decide to use composition instead of inheritance, it won’t break your code:

class Dog: private Animal
{
public:
    explicit Dog() {}
    Animal * GetAnimal() { return this; }
};

int main(int argc, char *argv[])
{
    Dog* pDog1 = new Dog();
    Animal * pDog2 = pDog1->GetAnimal();
    return 0;
}