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 ?