[LC++]virtual protected?

[Mark Phillips]

Hi Roberto,

> I mean I woul like to have a method which could be overided in the derived
> classes but not exposed in the objects..

What you want is the "protected:" interface.

> If I do:
> 
> class base
> {
>         protected:
>         virtual void doSomething ();
> };
> 
> The compiler complains..

What does it complain about?

The following code works fine for me (using g++).  I think it
is what you are trying to do.

#include <iostream>
using namespace std;

class baseTy {
private:
  int dataVt;
protected:
  virtual int f() const {
    return dataVt;
  }
public:
  baseTy(int dataAg=0): dataVt(dataAg) {}
  virtual ~baseTy() {}
};

class subTy: public baseTy {
protected:
  virtual int f() const {
    return 2*baseTy::f();
  }
public:
  int g() const {
    return f()*f();
  }
  subTy(int dataAg): baseTy(dataAg) {}
};

int main(int argc, char* argv[]) {
  subTy sub(3);
  cout<<"if data is 3, sub.g() is "<<sub.g()<<endl;
}



Cheers,

Mark.