Hi!
A derived class can override a method in the base class it inherits for,
and even my dog knows that. More incredibly, I know and understand it
too.
But, can a (of course virtual in this case) method be overriden in an
instance instead? For example, to provide some callbacks to a class.
Should I use virtual functions instead? How do I pass the this pointer
when casting it from or to in any useful way seems to break every C++
language rule? As a normal parameter? But then it doesn't really look
so OOP anymore.
Thanks a lot,
Tony
2  1658  to**@donotspamm e.ar wrote:
A derived class can override a method in the base class it inherits
for, and even my dog knows that. More incredibly, I know and
understand it too.
But, can a (of course virtual in this case) method be overriden in an
instance instead? For example, to provide some callbacks to a class.
No. For that you usually store pointers to [member] functions and assign
them different values based on the need, per instance.
Should I use virtual functions instead?
Instead of what? Instead of virtual functions? Uh... Yes!.. I mean,
no... I mean... Could you rephrase, please?
How do I pass the this pointer
when casting it from or to in any useful way seems to break every C++
language rule? As a normal parameter? But then it doesn't really look
so OOP anymore.
Huh? I think I don't understand (where does it place me relative to
your dog?), could you give an example in C++?
V
--
Please remove capital 'A's when replying by e-mail
I do not respond to top-posted replies, please don't ask to**@donotspamm e.ar wrote:
>
Hi!
A derived class can override a method in the base class it inherits for,
and even my dog knows that. More incredibly, I know and understand it
too.
But, can a (of course virtual in this case) method be overriden in an
instance instead? For example, to provide some callbacks to a class.
Should I use virtual functions instead? How do I pass the this pointer
when casting it from or to in any useful way seems to break every C++
language rule? As a normal parameter? But then it doesn't really look
so OOP anymore.
Virtual functions are type bound (although to the dynamic type). You can use
a function pointer or a member variable whose type is a function object if
you want to override the semantics of the call per instance.
Best
Kai-Uwe Bux This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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