Can you instantiate a class and then assign a different class to it using new (e.g. class1 name = new class2)

Question

I was watching a c++ tutorial about the "->" operator on youtube (the link ) in 2:48 of the tutorial. He wrote the code

int main()
{ScopedPtr entity = new Entity();}

from what I understand about instantiating class, the class behind new keyword should be the same as the class you are instantiating. Pls explain how this work and why it work.

FYI: I'm a beginner to coding and I do not have have guide books or anything I'm currently learning C++ from the youtube channel called Cherno, and whenever I don't understand something I just search up on the internet and go into website

Answer 1

Yes it may happen for instance when you create a pointer to an implementation of your classes where ScopedPtr is a pointer to the implementation of Entity.

You could have some documentation here or here

#include <iostream>

class Entity
{
public:
    Entity(){}
    //only for test
    void print()
    {
        std::cout << " print";
    }
};

class ScopedPtr
{
public:
    ScopedPtr(Entity* d) { implem = d;}
    ~ScopedPtr(){ delete implem;}

    //only for test
    void print()
    {
        implem->print();
    }
private:
    Entity* implem;
};

int main()
{
    ScopedPtr entity = new Entity();
    entity.print();
}