Re: why private virtual function?

From:
"Alf P. Steinbach" <alfps@start.no>
Newsgroups:
microsoft.public.vc.language
Date:
Mon, 17 Mar 2008 08:15:31 +0100
Message-ID:
<13ts6gpde7ad709@corp.supernews.com>
* Abhishek Padmanabh:

On Mar 16, 1:46 am, "Alf P. Steinbach" <al...@start.no> wrote:

Example:

<code>
class Base
{
private:
     void foo() {}
public:
     void bar() {}

};

struct Mixin { void foo() {} };

class Derived: public Base, public Mixin
{
public:
     void bar() { foo(); } // Uh oh.

};

int main()
{
     Derived().bar();}

</code>

In each specific case there are simple workarounds, e.g. here a
'using'-declaration or qualification, but IMHO there's something not quite right
about the scheme.


using declaration does not work here and rightly so. Something that is
private as declared by the "owner"/the base class itself should not be
easy enough to break into to make it visible. If the derived class
opts to take it (inherit) privately, using works and probably rightly
so as it is the decision of the derived class about what it wants.
Still, using declaration looks like a hack to circumvent the bad
decisions already taken or just a way to reuse code causing additional
coupling apart from what inheritance already causes.


I'm sorry, your comment is not meaningful to me, and it's also technically
incorrect.

It seems you have failed to understand the code, as well as what it was all about.

Try to compile the code, for example.

Cheers, & hth.,

- Alf

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