public static function contains($container, $val): bool
    {
        if (\is_array($container)) {
            return \in_array($val, $container, true);
        }
        
        if ($container instanceof \Traversable) {
            foreach ($container as $tmp) {
                if ($tmp === $val) {
                    return true;
                }
            }
        }
        
        return false;
    }