code: protected function parse_single($recursive = true) {
  		if (($c = $this->parse_conditions()) === false) {
  			return false;
  		}
  
  		$this->parse_callback($c, $recursive, $this->search_root);
  		return true;
  	}
docs: Parse first bit of query, only root node has to be evaluated now
  @param bool|int $recursive
  @return bool
  @internal Result of query is set in {@link $result}
  @access private