/**
  * Error location
  *
  * @return array|null
  */
 function getLocation()
 {
     if ($this->location) {
         return $this->location;
     }
     $entity = $this->entity;
     if (!$entity) {
         return null;
     }
     $path = array();
     $segment = $entity->getSegment();
     if ($segment) {
         $path[] = $segment->name;
         // Segment name
         $path[] = 1;
         // Segment sequence
         CHL7v2FieldItem::$_get_path_full = true;
         $path = array_merge($path, $entity->getPath());
         CHL7v2FieldItem::$_get_path_full = false;
     }
     return $path;
 }