[development] Hook ordering

[Karoly Negyesi]

----- Start Original Message -----
Sent: Wed, 03 Jan 2007 16:52:45 -0600
From: Scott McLewin <drupal at mclewin.com>
To: development at drupal.org
Subject: Re: [development] Hook ordering

> 
> Karoly Negyesi wrote:
> > In Drupal 6 I would like to see a hook registry -- mostly 
> > autodiscovered, but if you want ordering, then you can say "my 
> > implementation of hook_nodeapi is to be run before module 
> > this,that,foor,bar". Available in my sandbox,
> I don't know which sandbox is yours and didn't see 'knegyesi', 'negyesi' 
> or 'karoly' under 
> http://cvs.drupal.org/viewcvs/drupal/contributions/sandbox/.  So, 
> without looking at the code...

I need to work on my reputation :) 
http://cvs.drupal.org/viewcvs/drupal/contributions/sandbox/chx/weights.php?view=markup

> I agree that is a challenge, since the person who picked the 'first' 
> ordering may not run with the particular module combination that an 
> arbitrary site builder/admin will install.  I like the current pattern 
> of hook_load() and friends as being 'first' for a module that defines 
> its own type.  How about leaving that in place and only allowing 
> 'before' and 'after' designations in the proposed registry?

hook_load is not a real hook, it's a callback, because at any given time only one is called.
hook_nodeapi is a hook, at any given time all implementations are called in order.

For example, hook_form_alter. What happens when two modules try to be the first? Or the last for that matter?