// Neven-xpath.pdf
import edu.neu.ccs.demeter.dj.*;
import java.util.*;

XPath = List(Exp) EOF.
Exp : Simple | BinaryCompound | UnaryCompound common ["parent" <parent> Exp].
Simple : ElementTest | WildCard .
BinaryCompound = "(" BOp <arg1> Exp <arg2> Exp ")" .
UnaryCompound = "{-{" UOp <arg1> Exp "}-}" .
BOp : Disjunction | Child | Descendant | Filter.
UOp : Chi | Des.
Chi = "/".
Des = "desc".
Disjunction = "|".
Child = "/". 
Descendant = "desc" .
Filter = "filt".
ElementTest = Name.
WildCard = "*".
Name = Ident.

Main = <s> String.
List(S) ~ "(" {S} ")".

CountingVisitor = <c> int  extends Visitor .
ParentSettingVisitor = extends Visitor .