def attribute(type, method, attr)
      typed_attributes[type] << [method, attr]
      define_attribute(type, method, attr)
    end
def attribute(type, method, attr)
      typed_attributes[type] << [method, attr]
      define_attribute(type, method, attr)
    end
YARD macro to generated friendly
 documentation for attributes.

 @macro [attach] attribute
  @method $2
  @return [$1] value of $3 property