Proposing the removal of virtual_hooks (or how you can add a virtual method without using "virtual")

Thiago Macieira thiago at
Sun Mar 5 16:50:45 GMT 2006

Frans Englich wrote:
>On Saturday 04 March 2006 11:18, Thiago Macieira wrote:
>> I'd like to propose a change of policy in the KDE libraries: remove
>> all virtual_hook functions from QObject-derived classes.
>> The reason for that is that we *already* have a virtual_hook function
>> in those classes and it's called qt_metacall. It's automatically
>> generated by moc, so we're safe that it'll always exist.
>Another way to preserve BC is to use the visitor/double dispatch
> pattern. It can be argued to be a bit heavy code-wise, but achieves the
> goal and can also be fast, depending on various factors. Major
> pros/cons:

Would you mind elaborate on what that is?
  Thiago Macieira  -  thiago (AT) - thiago (AT)
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