Re: New 'GObject' as base for GtkObject?

[Owen Taylor <otaylor redhat com>]

Bill Huey <billh@burn.ucsd.edu> writes:

> > OK, I'm lost here. Java, as far as I know allows no
> > multiple-inheritance of implementation, while you are jumping through
> > large hoops to achieve multiple inheritance of data and member
> > functions.
> 
> Java has interface inheritence as a means of dealing with MI issues.
> 
> Wittness:
> 
> class ThreadInterface : Object
> {
> 	void Run()
> }
> 
> class DragNDropInterface : Object
> {
> 	void dragMethodA();
> 	...
> }
> 
> class TextFrame extends TextFrameParentClass		// inherits all sorts of from the parent object.
> 	implements DragNDropInterface, ThreadInterface	// include these interfaces and fill
> 							// in the object members.
> {
> 	...
> };

Hmmm, I pretty sure the above says "Java [...] allows no
multiple-inheritance of implementation". I don't see how your example
contradicts it.

You aren't saying that TextFrame inherits an implementation of
dragMethodA from DragNDropInterface - you are saying that TextFrame
implements dragMethod as part of an implementation of
DragNDropInterface.

(And BTW - there is no critique of Java implied in my statement.  I
quite like the design of the Java language, though the implementation
has typically fallen short.)
 
> Knowning modern OO design *should* be important for the Gtk core folks
> and not knowing that Java has a semi-form MI is a little peculiar to
> say the least.
> 
> > I think what you mean by having only virtual inheritance, is that
> > there is only one copy of each base class in the derived object, but I
> > don't really see how this makes it Java-like.
> 
> > But my basic opinion is that while it is neat, it is certainly far too
> > drastic a change to go into GTK+ in the near future ... it would
> > require rewriting large amounts of code in a very non-gradual fashion.
>  
> That's correct. "Neat" for you is means "zero hack" and "proper design"
> to me and others. From the looks of it (libgnome*) there's already some
> rather bizzare maintenance issues with Gtk/GNOME already.
> 
> > Also, right now I have no particular interest in having full multiple
> > inheritance of implementation within in GTK+, and I'm rather confident
> 
> MI is fairly important would normally indictate to me that folks the don't
> know it's benifits haven't use a modern GUI in the 90's. That's just bad.

Wow, what tact.
                                        Owen