Brandon Savage has posted the third part of his "Bug-Free" series to his blog today. This part focuses on the use of function traces to help narrow down the issue.

Have you ever been handed some code and told, "make it work"? If you haven't, chances are good you will some day. It's often a daunting task, especially since, as one programmer told me, "comments come when the second developer has to make changes." While this is likely bad coding practice, it's happened to me more than once.

Lucky for us, XDebug has a built-in tool that helps us evaluate code and figure out some of what is going on without spending all week reading the documentation or the code itself. It's called "function profiling."

He show how to use this profiling in your code, getting the trace results from a loop that outputs the ord() of a character (in the string "Xdebug"). He also talks about configuration changes you can make to include the parameters of the function call, the memory usage and the returns for each of the functions.