1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
class Customer < Struct.new(:name, :id) def to_param id.to_s end end class BadCustomer < Customer end class GoodCustomer < Customer end module Quiz class Question < Struct.new(:name, :id) def to_param id.to_s end end end