non virtual interfaces

[Alexandr Druzhinin]

20.09.2013 23:09, Jonathan M Davis пишет:
> You can use NVI with classes just fine just so long as you use protected rather
> than private, but making it private there won't work either, because private
> is never virtual (and it wouldn't really help you any if it were, because
> while the base class private function might not be callable, the derived class
> one would still be callable by the derived class, so trying to prevent the
> virtual function in NVI from ever being called outside of the base class is
> broken in the first place - including in C++ where it was originally devised).
> What NVI helps with is making it so that the public function being called as
> part of the API is non-virtual, allowing you to do stuff before and after the
> hidden virtual function being called, but the derived classes can still call
> their implementation of the hidden, virtual function.
>
> - Jonathan M Davis
>
I see. Thanks for clarifying.