XSLT Cookbook, 2nd Edition

Chapter 2. Strings

I believe everybody in the world should have guns. Citizens should have bazookas and rocket launchers too. I believe that all citizens should have their weapons of choice. However, I also believe that only I should have the ammunition. Because frankly, I wouldn’t trust the rest of the goobers with anything more dangerous than [a] string.

—Scott Adams

Introduction

When it comes to manipulating strings, XSLT 1.0 certainly lacks the heavy artillery of Perl. XSLT is a language optimized for processing XML markup, not strings. However, since XML is simply a structured form of text, string processing is inevitable in all but the most trivial transformation problems. Unfortunately, XSLT 1.0 has only nine standard functions for string processing. Java, on the other hand, has about two dozen, and Perl, the undisputed king of modern text-processing languages, has a couple dozen plus a highly advanced regular-expression engine.

With the emergence of XSLT 2.0 implementations, XSLT developers can dispense with their Perl string envy. XPath 2.0 now provides 20 functions related to string processing. The functions include support for regular expressions. In addition, XSLT 2.0 adds facilities for parsing unstructured text via regular expressions so it can be converted to proper XML.

XSLT 1.0 programmers have two choices when they need to perform advanced string processing. First, they can call out to external functions written in Java or some other language supported by their XSLT ...