private function applyPrefix($key)
    {
        $prefix = (string) $this->client->getOption(Redis::OPT_PREFIX);

        return $prefix.$key;
    }
private function applyPrefix($key)
    {
        $prefix = (string) $this->client->getOption(Redis::OPT_PREFIX);

        return $prefix.$key;
    }
private function applyPrefix ( $ key ) { $ prefix = ( string ) $ this -> client -> getOption ( Redis :: OPT_PREFIX ) ; return $ prefix . $ key ; }
Apply prefix to the given key if necessary.

@param  string  $key
@return string
Apply prefix to the given key if necessary .