Thread: about non-virtual func. in derived class

I have a question about polymorphism.
This is code

Code:

#include <iostream> 
using namespace std; 

class Pet {
 public: virtual void speak() const ; 
};
void Pet::speak() const { cout << "Hi" << endl; }

class Dog : public Pet { 
public: void speak() const { cout<<"hi too";} 
void eat() const { cout<<"eat"; }
 }; 

int main() { 
Dog simba; Pet* p=&simba; p->speak();//I can call dog::speak by pet pointer 
//p->eat(); but I can not call dog::eat() by pet. 
}

here how can i solve the problem.I mean i want to enhance my derived class and call my functions from base class pointer?

Is there a solution?
Thanks...

No. Change your pointer type or do a cast from Pet* to Dog* before accessing the function.

That might be an even better solution, but I'm not sure what OP is trying to do.

Just to expand on SlyMaelstrom's reply - the const qualifier has nothing to do with the return type of the function, be it "void", "int" or some other type. You can also have a const function which returns a const int, then you'd use the const keyword twice in the function declaration.

this example might be a good illustration (this deliberately won't compile.)

Code:

#include <iostream>
using namespace std;

class MyClass
{
   int i;
public:
   MyClass() : i(5) {}
   int geti() { return i;  }
       // geti() isn't const, it is free to modify the object.

};

int main()
{
   const MyClass MyObj;
   int x = MyObj.geti(); // ERROR!!  geti() may potentially modify MyObj.
   cout << x;
}

the compiler needs "const" after geti() as a promise that you are not going to modify MyObj.