The day has finally come, PHP 5.0 has been released. If for some reason you’ve been off the planet lately, PHP 5 is huge update to the guts of the PHP language. There is a long list of features and changes in this release. The MySQL client libraries are no longer included in releases (license issues aside this just makes sense, especially how old the client libraries they were including were) and SQLite is now included. The OO support has been heavily changed, most of which I’m happy with. I’m a bit disappointed that multiple inheritance is supported, in favor of the Java model of interfaces. I would have been happy with the Perl model of multiple inheritance.
There are has been lots of discussion about the new features of PHP 5, a good place to start is at the archive of PHP talks, many of which talk about PHP 5. Undoubtedly there will be some new books coming out about coding with PHP 5 in mind.
On another PHP front, Roadsend has release a PHP compiler for PHP 4. The benchmarks they list do show some impressive improvements in some areas. I think in the long run this sort of idea will either get swallowed up by the PHP project or only be useful to a smaller group of people.
So far I’ve resisted pretty heavily getting to involved with PHP 5. Now that there is non-beta release I’m going to swallow my pride and try it out. Initially my biggest concern is that all of my existing code based on PHP 4 works under PHP 5.
Update (6:47 pm 13 Jul 2004): Turns out there is PHP 4 to PHP 5 migration manual.
Update (3:09 pm 15 Jul 2004): Because OO support in PHP 5 has so many changes it may be helpful to read through the Classes and Object documentation specific to PHP 5. There are some sections that haven’t been filled in yet, but is still a good resource.