Re: Can this be used from Gtk2-perl? GtkDatabox

[muppet <scott asofyet org>]

On Apr 30, 2005, at 2:21 PM, zentara wrote:

> On Sat, 30 Apr 2005 11:02:06 -0400 muppet <scott asofyet org> wrote:
>
> > On Apr 30, 2005, at 9:55 AM, zentara wrote:
> >
> > >   GtkDatabox
> >
> > http://mail.gnome.org/archives/gtk-perl-list/2004-March/msg00077.html
>
> Hi, thanks, it runs good, and it is a nice example of doing xs with  
> Gtk2.

If i recall correctly (and i probably don't) i didn't put a whole lot  
of work into the binding -- i just did it to see if the thing was any  
good to use with a particular perl app i was working on.  I never did  
do any leak-testing on it.  Let me know if you have problems.


> I did notice 1 small error in the examples, which I have also seen   
> throughout
> the tutorials, that is using   :: notation where you need a  ->.

In what contexts in the tutorials?  When referring to a particular  
method the convention is to use the Fully::Qualified::method_name(),  
whereas when showing how to invoke something it will be  
$object->method_name().


> For example in lissajous.pl around line 75,
>
> #$window->signal_connect (destroy => \&Gkt2::main_quit);
> needs to be
> $window->signal_connect (destroy => sub {Gtk2->main_quit});

Congratulations!  You have found an "interesting" special case!

There's a default parameter on the class argument to Gtk2::main_quit()  
to allow it to be called with no argument.  This was done, IIRC,  
specifically to allow Gtk2::main_quit() to be used directly as a signal  
callback, without a useless closure.

Now, i say that was the reason, but in going back to the CVS logs to  
confirm this, i find that it is an undocumented feature that very well  
may have been committed by accident.
It happened in revision 1.39 of Gtk2.xs (just before the 1.04x stable  
series):
http://cvs.sourceforge.net/viewcvs.py/gtk2-perl/gtk2-perl-xs/Gtk2/xs/ 
Gtk2.xs?r1=1.38&r2=1.39
Interestingly, this is not mentioned in the ChangeLog entry, and isn't  
done for Gtk2::main().


> When I've been going thru the tutorials, I've seen this in quit a few  
> of
> the code snippets and code, and it probably will confuse alot of
> beginners...it took me a bit of time to figure it out. :-)

That's true.  Still, TIMTOWTDI.




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