Symfony validator without entities or objects

validator.php

<?php
// See http://symfony.com/doc/current/book/validation.html#validating-values-and-arrays
$email = $app['request']->get('email');
$emailConstraint = new \Symfony\Component\Validator\Constraints\Email();
$emailConstraint->message = 'Invalid email address';
$errorList = $val->validate(
  $email,
  $emailConstraint
);
var_dump($errorList);