From the newly revived phpPatterns.com this morning, there's a new quick piece about Implementing Lexers in PHP.

For those that are unsure, a lexer is used to help parse XML and other documents, and, according to this article, there's a posting over on the SitePoint forums that implements a simple Lexer that performs almost as well as the native PHP XML extension.

Needless to say, this is a great step forward for anyone that might need to work with XML in PHP, especially if you were using some of the native functionality. This piece also gives a few examples of projects where a lexer was used, and some more details on lexers and how they work...