var_export 没法解决循环引用问题，部分情况会导致内存溢出

        $stream = make(StreamHandler::class, [$dir . $filename, Logger::WARNING]);

        $fire = make(FirePHPHandler::class);

        if (is_array($output)) {

            $output = var_export($output, true);

            $output = print_r($output, true);

        }

        $output = '[ ' . date('Y-m-d H:i:s', time()) . ' ] --- ' . $output;

        $formatter = new LineFormatter($output . "\r\n");