/**
  *    _associate_attendee_with_registration
  *
  * @param EE_Registration $registration
  * @param EE_Attendee     $attendee
  * @return void
  */
 private function _associate_attendee_with_registration(EE_Registration $registration, EE_Attendee $attendee)
 {
     // add relation to attendee
     $registration->_add_relation_to($attendee, 'Attendee');
     $registration->set_attendee_id($attendee->ID());
     $registration->update_cache_after_object_save('Attendee', $attendee);
 }
 /**
  * _save_question_answers
  *
  * @param 	EE_Registration 	$registration
  * @param bool $show_errors
  * @return void
  */
 private function _save_registration_answers($registration, $show_errors = TRUE)
 {
     // now save the answers
     foreach ($registration->answers() as $cache_key => $answer) {
         // verify object
         if ($answer instanceof EE_Answer) {
             $answer->set_registration($registration->ID());
             $answer->save();
             if (!$registration->update_cache_after_object_save('Answer', $answer, $cache_key)) {
                 if ($show_errors) {
                     EE_Error::add_error(__('The newly saved Answer object could not be cached on the registration.', 'event_espresso'), __FILE__, __FUNCTION__, __LINE__);
                 }
             }
         } else {
             if ($show_errors) {
                 EE_Error::add_error(__('An invalid Answer object was discovered when attempting to save your registration information.', 'event_espresso'), __FILE__, __FUNCTION__, __LINE__);
             }
         }
     }
 }