> > module Mod
> >      alias_method :orig_exit, :exit
> >      def exit(code=0)
> >        puts "Exiting with code #{code}"
> >        orig_exit(code)
> >      end
> >    end
> > include Mod
> > exit(99)

> > Above snippet we are creating new alias (orig_exit) for already
> > existing method exit. Interesting thing is orig_exit is again called
> > in exit method, why won't this behavior cause recursive calling of
> > method it self since orig_exit is simply alias to exit method ?

> This is a pattern how to preserve original method that you want to override.
> Alias stores the method as it was when alias was called. When you
> override the method, the alias stil points to the old version --
> that's the point of this construct.

> J.