Re: Private method has been invokated as interface
Martin Bonner wrote:
Gerhard Menzl wrote:
Martin Bonner wrote:
[snip example of declaring a public virtual in a base
class, and then overriding it with a private member in a
derived class].
I am sorry, but I don't understand what your point is.
Yes, it is legal. No, it is not a good idea. So don't do
that.
I disagree. It is a perfectly natural technique for
implementing private callback interfaces (although
derivation is usually private in this case).
Yup. Francis made a similar comment.
[snip example]
Do you have a better way to implement this relationship and
express the intent of the design?
No. I think it is the best approach for that situation. I do
think it is worth a comment in the code (which you had in the
example I snipped), because it is (in my experience) unusual,
and even experienced programmers may be initiallly confused by
it.
The key thing which made his use logical was the fact that the
inheritance was private as well. IMHO, this is even more
important than the comment -- private inheritance is a sign that
everything concerning the inhertance is an implementation
detail. It also means that a user of MySubscriber can't simply
use static_cast< Subscriber* >( ptrMySubscriber ) to get around
the private.
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