private function splitSimpleAndNormalTransformations(array $transformations)
    {
        return array_reduce($transformations, function ($acc, $t) {
            return array(
                $t instanceof SimpleArgumentTransformation ? array_merge($acc[0], array($t)) : $acc[0],
                !$t instanceof SimpleArgumentTransformation ? array_merge($acc[1], array($t)) : $acc[1],
            );
        }, array(array(), array()));
    }