Can a sub-class (composite object) member function access private or protected members of base class

[pkpatil]

Hi,

Can a private composite object in a class access private or protected
members of base class?
For e.g.

class composite {
void memberFunction();
};

class main {
private:
int a;
composite comp;
protected:
int b;
};

Above, can composite::memberFunction() access main::a and main::b of
main class "main"? If so, how?

 

[Victor Bazarov]

Can a private composite object in a class access private or protected
members of base class?
For e.g.

class composite {
void memberFunction();
};

class main {
private:
int a;
composite comp;
protected:
int b;
};

Above, can composite::memberFunction() access main::a and main::b of
main class "main"? If so, how?

No, it cannot. The relationship exists between types and functions, not
between objects and classes or between objects and objects. In your case,
the 'composite::memberFunction' has no special access rights to class
'main'. To give the right to that function you need to declare it 'friend'
to 'main' class.

V

 

[Noah Roberts]

Hi,

Can a private composite object in a class access private or protected
members of base class?

There is no 'base class' in your example. Base classes are the class
that a derived class derives from. It has to do with inheritance, not
/composition/ as you show below.