class Module

def attr_internal_define(attr_name, type)
  internal_name = attr_internal_ivar_name(attr_name).sub(/\A@/, '')
  class_eval do # class_eval is necessary on 1.9 or else the methods a made private
    # use native attr_* methods as they are faster on some Ruby implementations
    send("attr_#{type}", internal_name)
  end
  attr_name, internal_name = "#{attr_name}=", "#{internal_name}=" if type == :writer
  alias_method attr_name, internal_name
  remove_method internal_name
end