Last night I was pondering how nice would it be to have a tool of some sort, that would simply spit out what version of PHP does my app require. Something like: here are my .php files, what PHP version and/or extensions do I need for it? First I thought about jumping right in and writing it myself, but hey, this kind of a tool sounds way to useful not to be written already! After a bit of a googling there it was: PHP_CompatInfo. A nice PEAR package that can tell me everything I want about my code and even a bit more.
He includes a code snippet showing it in action. It's a basic example that defines the driver type to use, options and the directory to parse through (using parseDir() naturally). Other output formats are available too like CSV and HTML.