DataMapper timzone enabled methods

zoned_times.rb

module ZonedTimes

  @@zoned_methods = []

  def self.included(base)
    base.extend(ClassMethods)
  end

  module ClassMethods

    def zoned_times(*args)
      if args.empty?
        @@zoned_methods
      else
        @@zoned_methods = args
        create_zoned_accessors
      end
    end

    def create_zoned_accessors
      @@zoned_methods.each do |method|
        User.module_eval{
          define_method(method){|*args|
            return super() if args.empty?
            return super().in_time_zone(args[0])
          }
        }
      end
    end
  end
end

1.9.3p484 :001 > User.first.created_at
=> Thu, 19 Dec 2013 13:02:30 +0000
1.9.3p484 :002 > User.first.created_at('Buenos Aires')
=> Thu, 19 Dec 2013 10:02:30 ART -03:00