self-referencing function for printing errors from the form

example.php

<?php
$errors = function($field) use (&$errors) {
    $result = array(
        'errors' => $field->getErrors(),
        'children' => array()
    );

    foreach ($field as $name => $child) {
        $result['children'][$name] = $errors($child);
    }

    return $result;
};

usage.php

<?php

var_dump(array($form->getName() => $errors($form)));