Discussion and considerations

Let's consider the need for each of these in turn. There is no particular link between them; they are simply gathered together for convenience.

Parsing XML

The use of XML has become widespread. It works well as a standardized way to deal with information that has structure but is most conveniently handled as plain text. For the purposes of a CMS framework, there is usually no need to perform manipulation of XML documents. What is required is efficient parsing of XML to create data structures that can be easily used within the CMS software.

XML parsing was provided in PHP4, and as a standard feature could always be safely used. In PHP5, much more powerful XML options are introduced, and to parse XML it is possible to reduce the amount of PHP code significantly by using SimpleXML in place of earlier parsing functions. There is a slight risk since SimpleXML is an extension, but it is included by default so it is not unreasonable to build our framework on the assumption...