On DevShed today, they've posted this new tutorial continuing their "recursion in PHP" series - "Developing a Discussion Forum in PHP with Recursion".
After covering in detail how to define recursive method and functions, the question is: what comes next? Luckily, there's vast terrain to explore with reference to using recursion in PHP. As I said in previous articles of this series, recursion can be used in cases where a specific tree structure or a linked list needs to be navigated, in order to display, add, delete or edit its values. It's exactly for that reason that this last article will be focused on building an extensible discussion forum, which precisely uses a tree structure (implemented on a single MySQL database table) for displaying forum messages and adding new posts.
Using what they've taught in the first two parts of the series, they put it to good use, giving you a step-by-step guide to a simple recursive forum. They start with the database structure (always a good thing) and work out from there, creating the "ThreadProcessor" class and fetch functionality to grab the thread's contents. They also include a bit of functionality to create threads as well. It's not much more than that, so don't expect too much, but it is a great place to start.