gistfile1.rb

require 'singleton'
require 'yaml'

module BoxGrinder
  class PluginManager < Array
    include Singleton
  end

  class OperatingSystemPluginManager < PluginManager
  end

  class OperatingSystemPlugin
    def self.inherited(klass)
      OperatingSystemPluginManager.instance << klass.new
    end

    def name
    end

    def supported_versions
      []
    end

  end

  class FedoraPlugin < OperatingSystemPlugin
    def name
      "fedora"
    end

    def supported_versions
      ['11', '12']
    end
  end
end

os_plugin_manager = BoxGrinder::OperatingSystemPluginManager.instance

puts "We have #{os_plugin_manager.size} plugin(s) registered."

os_plugin_manager.each do |plugin|
  puts "Plugin for #{plugin.name} #{plugin.supported_versions.join(', ')}."
end



[oddthesis@lolek-f12 managers]$ ruby plugin-manager.rb 
We have 1 plugin(s) registered.
Plugin for fedora 11, 12.