Is it possible to return descendants of an abstract class from a function?

Question

OOP

There is a function that, depending on the input value, creates an object of a certain class, which is inherited from the abstract one. Is it possible somehow to return this object by reference to the base class, without creating it through new and not by pointer?

Answer 1

Yes, you can.

#include <iostream>

struct Abstract
{
    virtual void print() = 0;
    virtual ~Abstract() = default;
};

struct Concrete : Abstract
{
    virtual void print() override
    {
        std::cout << "Concrete\n";   
    }

};

Abstract& foo()
{
   static Concrete c;
   return c;   
}

int main()
{
    foo().print();
}

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