[Qt-interest] Virtual signals in base class?

[Anders Bakken]

On Thu, Sep 09, 2010 at 12:49:26AM -0700, Robert Caldecott wrote:
> Whilst reviewing some Qt C++ code I came across this:
> 
> class Foo
> {
>   Q_OBJECT
> 
> signals:
>   virtual void someSignal(const QString& str, int n)
>   {
>     Q_UNUSED(str);
>     Q_UNUSED(n);
>   }
>   ...
> };
> 
> Now, Qt signals cannot have a body so I'm surprised this even compiles
> (perhaps because the body is effectively empty). I also don't see the
> point of making a signal virtual (as it can't have a body so how can
> it be overridden?)
> 
> Am I missing something here or is this code actually valid?

My best guess is that this code is not moc'ed so the generated function
is never compiled (or even generated). 

regards
-- 
Anders Bakken