/** * Enter description here... * * @param string|pQueryObject * @return pQueryObject|QueryTemplatesSource|QueryTemplatesParse|QueryTemplatesSourceQuery */ public function add($selector = null) { if (!$selector) { return $this; } $stack = array(); $this->elementsBackup = $this->elements; $found = pQuery::pq($selector, $this->getDocumentID()); $this->merge($found->elements); return $this->newInstance(); }