XSLT 2.0 and XPath 2.0 Programmer's Reference, 4th Edition

Chapter 12. XSLT Patterns

A pattern is used in XSLT to define a condition that a node must satisfy in order to be selected. The most common use of patterns is in the match attribute of <xsl:template>, where the pattern says which nodes the template rule applies to. For example, <xsl:template match ="abstract" introduces a template rule that matches every <abstract> element. This chapter defines the syntax and meaning of XSLT patterns.

Patterns (sometimes called match patterns) are used in just six places in an XSLT stylesheet:

• In the match attribute of <xsl:template>, to define the nodes in a source document to which a template applies

• In the match attribute of <xsl:key>, to define the nodes in a source document to which a key definition applies

• In the count and from attributes of <xsl:number>, to define which nodes are counted when generating numbers

• In the group-starting-with and group-ending-with attributes of <xsl:for-each-group>, to identify a node that acts as the initial or final node in a group of related nodes

Patterns and Expressions

Most of the patterns found in stylesheets are simple and intuitive. For example:

Pattern	Meaning
title	Matches any <title> element
chapter/title	Matches any <title> element whose parent is a <chapter> element
speech[speaker = "Hamlet"]	Matches any <speech> element that has a child <speaker> element whose value is «Hamlet»
section/para[1]	Matches any <para> element that is the first <para> child of a <section> element

The rules for the more complex patterns, ...