On Wed, Apr 24, 2002 at 10:40:09AM -0400, Dan McCormick wrote:
> Hi,
>
> Does anyone have any advice for writing a POE object/session in such a
> way that the main program doesn't need to know all its states?
>
> The problem is that if you write 20 programs that use one POE
> object/session, and then add an internal, private state to that
> object/session, it won't be able to call it without modifications to all
> 20 programs, assuming you've created the object/session in each of the
> 20 programs like...
>
> POE::Session->create(
> object_states => [ ... ]
> );
>
> It looks like IKC handles this by exporting subroutines that create the
> sessions, which the main programs then call. Are there any other
> approaches?
I do it the same way. Basically, write a function that acts as the
Session's constructor or spawner.
If you'd rather have the create() constructor calls in the main
program, you can have your object export a list or hash for the value
of object_states. The work-around looks like this:
package Thingy;
use Exporter;
my @thingy_states = qw(_start _stop etc and so on);
use vars qw(ISA EXPORT_OK);
@ISA = qw(Exporter);
@EXPORT_OK = qw(@thingy_states);
...;
package main;
use Thingy qw(@thingy_states);
POE::Session->create(
object_states => \@thingy_states,
);
...;
Be sure to update @thingy_states when you change Thingy's states, and
you're all set.
-- Rocco Caputo / [EMAIL PROTECTED] / poe.perl.org / poe.sf.net
