public function getIterator()
    {
        $iterator = new PriorityList();
        $iterator->isLIFO(false);

        foreach ($this->activeForms as $key) {
            $spec = $this->forms[$key];
            $priority = isset($spec['priority']) ? $spec['priority'] : 0;

            $iterator->insert($key, $this->getForm($key), $priority);
        }

        return $iterator;
    }