Re: Undo framework

[Rodrigo Moya <rodrigo gnome-db org>]

On Fri, 2007-09-21 at 16:21 -0300, Johan Dahlin wrote:
> 
> > 3) Gtk seems like the right place for widgets to display the
> >    undo/redo stack.  However, the core of the functionality seems
> >    non-gui.  Something that would belong wherever we chose to put
> >    GDocument.  To date that type of code has been migrating out of
> >    gnumeric and into goffice.  If there is interest, we could
> >    collaborate on the next generation of this in there and rename to
> >    'libgdocument' or somesuch.
> 
> While I agree that an undo stack should be in Gtk+ or lower I'm not sure a 
> transaction based should go there, but it should be possible to implement 
> one top of the interfaces/manager objects there.
> 
> I'm not sure we should talk about a 'document' there, there are many 
> operations outside of documents which are undoable.
> 
yes, we are not talking only about document, and yes, I think it should
be in Glib, except for the widgets that might be needed.

As for transation-based framework, I'm not sure exactly what Jody is
thinking about, but to me, if I understood it correctly, it makes a lot
of sense to be able to group performed actions into a set that can be
undone/redone and even repeated. That would, probably, fit the GIMP's
needs, as stated by Sven, to have nested undo groups. Each group would
be a transaction, that can be redone/undone/repeated as a single entity.
-- 
Rodrigo Moya <rodrigo gnome-db org>