public function enterNode(Node $node)
    {
        if (!$node instanceof Instanceof_) {
            return;
        }

        if (($node->expr instanceof Scalar && !$node->expr instanceof Encapsed) || $node->expr instanceof ConstFetch) {
            throw new FatalErrorException(self::EXCEPTION_MSG, 0, E_ERROR, null, $node->getLine());
        }
    }