public function get_choices(ImsQtiReader $reader)
 {
     $result = array();
     $choices = $reader->query('.//def:simpleAssociableChoice');
     foreach ($choices as $choice) {
         $id = $choice->identifier;
         $text = $this->to_text($choice);
         $max = $choice->matchMax;
         // not handled by moodle
         $result[$id] = $this->create_choice($id, $text, $max);
     }
     return $result;
 }
 protected function is_question_file($path)
 {
     $name = basename($path);
     $ext = pathinfo($path, PATHINFO_EXTENSION);
     if (empty($ext) || $ext != 'xml' || self::IMS_MANIFEST_NAME == $name) {
         return false;
     }
     $reader = new ImsQtiReader();
     $reader->load($path);
     return count($reader->query('/def:assessmentItem')) > 0;
 }