From: Philip Mak <pmak@...>
Date: 2002-08-27T12:54:56+09:00
Subject: Re: Getting list of classes in a module?

> Try this:
>
> def classes_under( mod )
>   mod.constants.map {|name| mod.const_get(name) }.select {|v| Class === v }
> end
> classes_under(YourFavoriteModule)

Thanks! I ended up doing this, which is essentially the same but a bit
simpler:

def classes_under(mod)
  mod.constants.select{|v| mod.const_get(v).type == Class}
end