Chapter Roadmap

This chapter focuses on solving problems using the tree-based XML parser modules. In Chapter 3, "Event-Driven Parser Modules," we discussed the concept of an event-based parser. If you remember, some of the event-based parsers discussed in Chapter 3 were based on the SAX standard while others were not.We have a similar situation again in this chapter. While all the modules discussed in this chapter can be considered tree-based, not all the XML parser modules are based on the Document Object Model (DOM) standard.We'll discuss the concept of a tree-based parser, then the non-DOM-compliant XML parser modules, and finally the DOM and the DOM-compliant modules.

To run all the examples discussed in this chapter, you need to install the following Perl modules:

• XML::Simple

• XML::Twig

• XML::DOM

• XML::LibXML

• XML::Xerces

Note

If you have any questions about Perl modules (for example, where to get them, how to install them, and so forth), please refer to Appendix B, "Perl Essentials."