/**
  * Return memc value if not expired
  * @param object|bool $data makeMemcObj() tuple
  * @param Page $article
  * @param string $allowStale Use 'allowStale' to skip page_touched check
  * @return mixed
  */
 public static function getMemcValue($data, Page $article, $allowStale = '')
 {
     if (is_object($data)) {
         if ($allowStale === 'allowStale' || $data->time >= $article->getTouched()) {
             return $data->value;
         }
     }
     return false;
 }