/**
  * @return Form
  **/
 private function importPrimitive($scope, BasePrimitive $prm)
 {
     if (!$this->importFiltering) {
         if ($prm instanceof FiltrablePrimitive) {
             $chain = $prm->getImportFilter();
             $prm->dropImportFilters();
             $result = $this->checkImportResult($prm, $prm->import($scope));
             $prm->setImportFilter($chain);
             return $result;
         } elseif ($prm instanceof PrimitiveForm) {
             return $this->checkImportResult($prm, $prm->unfilteredImport($scope));
         }
     }
     return $this->checkImportResult($prm, $prm->import($scope));
 }