From: Luke Kanies <luke@...>
Date: 2006-08-02T08:29:59+09:00
Subject: Re: Strategies for autoloading ruby files

ara.t.howard@noaa.gov wrote:
>   module Plugable
>     def self.included other
>       ...
>     end
>   end
> 
>   class MyPlugin
>     include Plugable
>   end

At this point, I'm looking at creating an Autoload class, and classes 
wanting to autoload will create an instance:

   Puppet::Autoload.new(self, "puppet/type")

They'll then be able to store that instance, or retrieve it from the class:

   Puppet::Autoload[self].load(:package)

That'll handle the mechanics of the loading.  I'll have an additional 
:loadall method that will search through $:, loading everything that 
matches.

I want to keep the work around plugin loading -- that is, what to do 
with the class and how to initialize it -- in the class supporting 
plugins (i.e., the class with the 'new<thing>' method), because most 
initialization is pretty custom.  I suppose I could start with a default 
method in a module, though; I hadn't thought much about that.

A significant part of this for me is that I have lots of classes that 
are related to each other -- the Puppet::Type class is related to its 
subclasses, the Puppet::Type::Package class is related to the 
Puppet::Type::Package::PkgType classes (ugh, constants are hard), the 
'service' class is related to each 'svctype' class, etc.  Calling 
'new<thing>' directly on the related class makes that relationship very 
explicit and pleasantly clear.

> yes - i've got a fair number of class factories lying around myself.
> Class.new is powerfull since you can easily parameterize your classes.

I *love* Class.new and Module.new.  Ruby was great before I discovered 
them, but with them, I'm definitely hooked.  Well, Class.new and 
class_eval, anyway.

> on a related note i used 'traits' alot with this sort of thing since it 
> avoids
> needing to initialize all those class vars directly down the inheritence
> chain.

Most of the variables involved are actually class instance variables 
(which, I understand, others don't use that much, but which I use 
pervasively and could not live without).

I need to just add traits into my codebase; I think it would simplify a 
lot of what I'm doing.

/me adds one more item to the todo

> i'll read over some over of you code but gotta run to get the kid...

Comments, positive or negative, are always appreciated.

-- 
Today I dialed a wrong number...The other person said, "Hello?" and
I said, "Hello, could I speak to Joey?"...
They said, "Uh...I don't think so...he's only 2 months old."
I said, "I'll wait."  -- Steven Wright
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Luke Kanies | http://reductivelabs.com | http://madstop.com