For an overloaded function, calling specialized version for parent and child instances

Question

I asked a question earlier but it turns out my problem was not properly modeled by my example. So here is my actual problem:

1. I have class A, and c

Answer 1

Antonio wrote a good solution involving virtual functions. If you really do not want to use a virtual function for some reason, then you can use dynamic_cast in a free function instead:

#include 
#include 

struct A {
    virtual ~A() {}   // important
};

struct B : A {};

void bar(A &a) { std::cout << "This is an A" << std::endl; }
void bar(B &b) { std::cout << "This is a B" << std::endl; }

void bar_helper(A *ptr)
{
    if ( auto b = dynamic_cast(ptr) )
        bar(*b);
    else
        bar(*ptr);
}

int main()
{
    std::list ls;
    ls.push_back(new B);
    ls.push_back(new B);
    ls.push_back(new A);

    for (auto ptr : ls)
    {
        bar_helper(ptr);
        delete ptr;
    }
    ls.clear();
}