ShoeOrder =			"<ShoeOrder>" "id=" <id> String "style=" <style> String "<color>" <color> Ident "</color>" "<size>" <size> String "</size>" <width> Width ["<stores>" <stores> Store_List "</stores>"] "</ShoeOrder>".

Width =			"<width>" <w> W "</width>".

W :			AA
			| EE			.

AA =			"aa" extends W.

EE =			"ee" extends W.

Store =			<name> Ident <howManySuchShoes> Quantity.

Quantity =			<number> Number.

Main =			.

visitors

visitor SummingVisitor =			<total> int extends UniversalVisitor.

notparsed visitor visitor PrintVisitor =			<indent> int <needSpace> boolean extends UniversalVisitor.

notparsed visitor visitor CopyVisitor =			<copy> derived Object extends UniversalVisitor.

notparsed visitor visitor SubgraphVisitor =			<is_equal> boolean init {{ true }} extends UniversalVisitor.

notparsed visitor visitor EqualVisitor =			<is_equal> boolean init {{ true }} extends UniversalVisitor.

notparsed visitor visitor DisplayVisitor =			<indent> int extends UniversalVisitor.

notparsed visitor visitor TraceVisitor =			<indent> int extends UniversalVisitor.

notparsed visitor visitor UniversalVisitor :						.
			
			Store_List =			[ <first> Nonempty_Store_List].
			
			Nonempty_Store_List =			<it> Store [ <next> Nonempty_Store_List].