In article <rtj0leav1iv71@corp.supernews.com>, Maxim Veselyy
<MVeselyy@software-automation.com> writes
>
>I remember seeing it somewhere that when deriving the class with private
>members you can change Access Privileges to a member by declaring in public
>or protected section of derived class .
>
>class Base {
>  int a;
>};
>class Derived : public Base {
> public :
>  int Base::a;
>
>};
>
>for some reason it does not work with VC++ 6.0.

Nor should it. It makes a world of difference whether you are dealing
with private or protected access.  Derived has no access privileges to
private items in Base.

Change Base to
class Base {
protected:
        int a;
};

and update Derived to the modern idiom:


class Derived: public Base {
public:
        using Base::a;
};

and you should not get a complaint from the compiler.  However you will
get strong complaints from competent C++ programmers that you need quite
exceptional reasons to do such a thing.



>

Francis Glassborow      Journal Editor, Association of C & C++ Users
64 Southfield Rd
Oxford OX4 1PA          +44(0)1865 246490
All opinions are mine and do not represent those of any organisation
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I remember seeing it somewhere that when deriving the class with private
members you can change Access Privileges to a member by declaring in public
or protected section of derived class .

class Base {
  int a;
};
class Derived : public Base {
 public :
  int Base::a;

};

for some reason it does not work with VC++ 6.0.





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MVeselyy@software-automation.com (Maxim Veselyy) wrote in comp.std.c++:
>I remember seeing it somewhere that when deriving the class with private
>members you can change Access Privileges to a member by declaring in public
>or protected section of derived class .

I don't think so. According to Stroustrup's D&E, one of the basic
principles of C++ is that access can only be granted, never unilaterally
taken.

Therefore, if I understand correctly, no private members of a base class
are accessible to a derived class unless the base class makes the derived
class a friend.

--
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