How do I validate an array of integers in Laravel

Validator::extend('numericarray', function($attribute, $value, $parameters)
{
    foreach($value as $v) {
         if(!is_int($v)) return false;
    }
    return true;
});

Use it

$rules = array('someVar'=>'required|array|numericarray')

Edit: Up to date version of this validation would not require the definition of numericarray method.

$rules = [
    'someVar'   => 'required|array',
    'someVar.*' => 'integer',
];

In Laravel 5 you can check the elements in an array by using .*. For you this would mean:

$rules = array('someVar'   => 'required|array',
               'someVar.*' => 'integer')

Now laravel has option to set condition on array elements. No need to write your own validator for simple things like validation int array. Use this (if using in controller)-

$validator = \Validator::make(compact('someVar'), [
    'someVar' => 'required|array',
    'someVar.*' => 'integer'
]);
$this->validateWith($validator);

or

$this->validate($request, [
    'someVar' => 'array',
    'someVar.*' => 'int'
]);