Re: Stealing a good idea from Gtk#

[Torsten Schoenfeld <kaffeetisch gmx de>]

On Mon, 2004-09-27 at 02:00, A. Pagaltzis wrote:

> >   $button -> Clicked += \&clicked;
>
> It's definitely cool. Three things irk me, though:

Jeez, you all are one big bunch of critics.

>     a) += just isn't used that way in Perl, and I think
>        overloading its meaning the way its done here is too
>        idiosyncratic.

Point taken.  The way I think about it is this: The installed method
represents a signal which in turn is a kind of container for all signal
handlers connected to it.  So when you do +=, you add a handler to the
list of handlers.

>     b) There is no indication that we're doing something with a
>        signal here, not just using any old mutator.

"If it was hard to write, it should be hard to understand."
  -- The Real Programmer

>     c) StudlyCaps, particularly as a vehicle to solve namespace
>        clashes.

Yeah, that irked me too.

> It is completely untested, but if I didn't screw it up too
> thoroughly, you should now be able to say 

You'd need to at least get rid of the "return".  perlsub says:

      You can't use the return keyword, you must pass out the value
      before falling out of subroutine scope. (see comment in example
      above).  This is usually not a problem, but it disallows an
      explicit return out of a deeply nested loop, which is sometimes a
      nice way out.

>     $window->SIGNAL::delete_event = sub {
>         Gtk2->main_quit();
>         return FALSE;
>     };

In addition to what muppet already said (using an assignment when you're
actually adding a handler to a list of handlers), I'm not fond of
introducing a global namespace for something that is Glib-specific.

Leaving that aside, I really do like your approach too.  AUTOLOAD,
lvalue subs, tie -- all the cool magic in just a few lines of Perl.

-- 
Bye,
-Torsten