From: Tim Hunter <cyclists@...>
Date: 2004-11-05T07:18:43+09:00
Subject: How to enumerate nested classes

I have a class nested in a module:

module Foo
   class Bar
   ... buncha stuff here
   end
end

Within Foo::Bar there are many nested classes, not necessarily descended
from Bar, simply contained within its namespace.

I would like to write a test that ensures that each class contained within
Foo::Bar has a method named deep_copy() somewhere in its inheritence
hierarchy. I'd like to write the test without explicitly listing all the
nested classes. That is, if I add another class to Foo::Bar, then the test
automatically checks it as well.

I thought I could do this via ObjectSpace.each_object(Foo::Bar) but that
doesn't work. I also tried getting a list of Foo::Bar's constants and going
from there but I got nowhere.

Any ideas?