Class 'PhpParser\Parser\Php7' not found Laravel when using Mail

I had no problems since a week ago, now when I try to send a Mail via : Mail::queue('myemail', $data, function($message) use ($data){....});

I have the following error :

FatalErrorException in ParserFactory.php line 27:
Class 'PhpParser\Parser\Php7' not found

what can I do to solve this issue ? I'm using wampserver 3.0.4 and laravel 5.2

via Chebli Mohamed