From: Robert Klemme <bob.news@...>
Date: 2003-11-20T23:37:20+09:00
Subject: Re: Plugin-API


"Christian Kruse" <ckruse@defunced.de> schrieb im Newsbeitrag
news:8mgipb.a13.ln@news.defunced.de...
> Hi there,
>
> I'm writing an application in Ruby which should be easy to extend. One
> should be able to write a plugin for this application and should be able
> to load it with an entry in the config file, e.g.
>
>   Load ContentFilter
>
> Perl I would use eval statements like
>
>   eval "use $modname";
>   die $@ if $@;
>
> to load the plugin. In Perl the plugin would look like the following:
>
>   push @{$main::Plugins->{state}},new Module;
>
>   package Module;
>
>   sub new() {
>   }
>   ....
>
>   1;
>
> What's the "ruby way" to do this?

Assuming the config file is evaluated as ruby code you can do:

15:33:28 [temp]: for file in PluginBase.rb SomePlugin.rb config.rb
application.rb ; do echo "---- $file ----" ; cat "$file" ; done
---- PluginBase.rb ----
class PluginBase
end

---- SomePlugin.rb ----
require 'PluginBase'

class PluginClass < PluginBase
  # functionality
end

$plugin_registry << PluginClass
---- config.rb ----
require 'SomePlugin'

---- application.rb ----
# other classes

$plugin_registry = []

eval File.readlines("config.rb").join

p $plugin_registry

15:33:36 [temp]:


As easy as that...

    robert