From: masa Date: 2011-02-04T21:26:02+09:00 Subject: Re: Arrays and defs My recommends are 1. overwrite Array class Array def do_stuff() self.each_index do |i| puts self[i] end end end 2. include module module MyModule def do_stuff() self.each_index do |i| puts self[i] end end end class Array include MyModule end Then list = Array.new list = ["a", "b", "c"] list.do_stuff Or you can include the module to any class inherits Array class as you like like here class MyClass < Array include MyModule end Best Masa