Re: Fake inheritance in GDK

[Owen Taylor <otaylor redhat com>]

murrayc t-online de (Murray Cumming) writes:

> I'm auto-generating C++ wrappers for GDK 2, and I've discovered some
> small difficulties:
> 
> GdkVisualClass is declared as this, in gdkvisual.h:
> 
> typedef struct _GdkVisualClass    GdkVisualClass;
> 
> But _GdkVisualClass is not defined anywhere. I think that it should, at
> least, be defined as 
> typedef struct _GdkDrawableClass    GdkVisualClass
> as has been done for GdkPixmap and GdkBitmap in gdktypes.h

GdkVisual is not a GdkDrawable:

 http://developer.gnome.org/doc/API/2.0/gdk/gdk-visuals.html
 
explains what a GdkVisual is.

> Actually, I'd like to change all of these pretend derivations to real
> derivations. The C++ compiler can't tell the difference between
> GdkDrawable*, GdkBitmap*, GdkPixmap*, and GdkVisual* because they are
> all simple typedefs of each other. Would you accept a patch to do that?

No. Breaking every GTK+ program out there not allowed. :-)

(They actually are real derivations, in the GObject sense, we just
use the same typedef for all of the objects.)

Regards,
                                        Owen