public function dieOnCircularReference(&$stk, Project $p)
 {
     if ($this->checked) {
         return;
     }
     if ($this->isReference()) {
         parent::dieOnCircularReference($stk, $p);
     } else {
         foreach ($this->selectorsList as $fileSelector) {
             if ($fileSelector instanceof DataType) {
                 self::pushAndInvokeCircularReferenceCheck($fileSelector, $stk, $p);
             }
         }
         $this->checked = true;
     }
 }