protected function _jig($id,$pw,$realm) {
		$success = (bool)
			call_user_func_array(
				[$this->mapper,'load'],
				[
					array_merge(
						[
							'@'.$this->args['id'].'==?'.
							($this->func?'':' AND @'.$this->args['pw'].'==?').
							(isset($this->args['realm'])?
								(' AND @'.$this->args['realm'].'==?'):''),
							$id
						],
						($this->func?[]:[$pw]),
						(isset($this->args['realm'])?[$realm]:[])
					)
				]
			);
		if ($success && $this->func)
			$success = call_user_func($this->func,$pw,$this->mapper->get($this->args['pw']));
		return $success;
	}