Real World XML

XPointer Predicates

XPointers support the same types of expressions as XPaths. As in Chapter 13, these are the possible types of expressions you can use in predicates (refer to Chapter 13 for more information):

• Node sets (although they're called location sets in XPointer)

• Booleans

• Numbers

• Strings

• Result tree fragments

XPointer also makes some additions to the functions that return location sets, and I'll take a look at those functions now.