Re: Can't add new GTK 2.16 methods to GtkStyle

[Torsten Schoenfeld <kaffeetisch gmx de>]

Kevin Ryde wrote:
> > In generic code, you can never be sure that calling get_property() on
> > an object will invoke Glib::Object::get_property().  You'd have to
> > fully specify the method name to be sure.
>
> Really?  It seems a bit un-oop-ish to give a full name, since if I'm not
> mistaken it would bypass anyone else's subclassing too (though I can't
> think of much besides call snooping that a subclass might legitimately
> do).

Yes, calling get_property() by its full name would bypass any overrides from 
subclasses.  But I think that's fair; if you want to do unusual things when 
get_property() is called, do it in the GET_PROPERTY() vfunc.

> Would the code in tie_properties() be giving full names?  The unhappy
> surprise for a generic bit like tie_properties() would be that
> get_property / set_property don't match what list_properties,
> find_property and the notify:prop signal name stuff say.
>
> Because there's no properties on GtkStyle I suppose not too much can go
> wrong.  But in the worst case you could imagine a different get_property
> may even be incompatible for an object inspector, if someone has been
> walking all objects with Devel::FindBlessedRefs or the like and hoping
> the names from list_properties can be accessed with get_property.

These are good points.  There might be a lot of code out there relying on 
get_property() being Glib::Object::get_property().  I still think that's broken, 
since there's no guarantee that subclasses avoid naming methods "get_property". 
 But maybe we should declare this a case of "don't do that!".

So, if we want to install such a "social rule", we have to adhere to it in 
Gtk2::Style too.  As I see it, there are two ways to do that:

• Make Gtk2::Style::get() call gtk_style_get(), but leave get_property() alone. 
 This has a precedent in Gtk2::TreeModel.  But unlike in the Gtk2::TreeModel 
case, the C API also provides gtk_style_get_property(), and people seeing that 
might expect that calling get_property() on a Gtk2::Style invokes it.

• Use different names for the wrappers, e.g. Gtk2::Style::get_style_property() 
for gtk_style_get_property().  This has the disadvantage of deviating from the 
usual mapping from C function names to Perl method names.  And what would we 
call the gtk_style_get() wrapper?  Or would we only provide get_style_property()?

Should we do one of the above, or leave things as they are now?  What do you all 
think?