Keep track of classes including the module

gistfile1.rb

ruby-1.9.2-p180-patched :001 > module Test
ruby-1.9.2-p180-patched :002?>   def self.included(base)
ruby-1.9.2-p180-patched :003?>     @classes ||= []
ruby-1.9.2-p180-patched :004?>     @classes << base
ruby-1.9.2-p180-patched :005?>     end
ruby-1.9.2-p180-patched :006?>   def self.classes
ruby-1.9.2-p180-patched :007?>     @classes
ruby-1.9.2-p180-patched :008?>     end
ruby-1.9.2-p180-patched :009?>   end
 => nil 
ruby-1.9.2-p180-patched :010 > class Hello
ruby-1.9.2-p180-patched :011?>   include Test
ruby-1.9.2-p180-patched :012?>   end
 => Hello 
ruby-1.9.2-p180-patched :013 > Test.classes
 => [Hello]