function devoid($key) {
		$val=$this->ref($key,FALSE);
		return empty($val) &&
			(!Cache::instance()->exists($this->hash($key).'.var',$val) ||
				!$val);
	}
function devoid($key) {
		$val=$this->ref($key,FALSE);
		return empty($val) &&
			(!Cache::instance()->exists($this->hash($key).'.var',$val) ||
				!$val);
	}
function devoid ( $ key ) { $ val = $ this -> ref ( $ key , FALSE ) ; return empty ( $ val ) && ( ! Cache :: instance ( ) -> exists ( $ this -> hash ( $ key ) . '.var' , $ val ) || ! $ val ) ; }
Return TRUE if hive key is empty and not cached
@return bool
@param $key string
Return TRUE if hive key is empty and not cached