For the next alpha release of PEAR that will happen in 2 - 4 weeks we'll have a min dep of PHP 4.4 and 5.1.6, so basically excluding 5.0.0 - 5.1.5 Now why am I going to do that?

This pushes more people up from the PHP 4.3.x series (to the 4.4.x that was the last PHP4 release) and up to a more recent PHP5 version for the future. Eventually, PHP4 support will be dropped all together, but for now there's a bit of a hold out.

In lack of better words, I'll call this compositional programming style. It's a style which is usually more prevalent with experienced programmers. [...] There is, however, a dark side to composition - dependencies.

He starts with a definition to bring everyone up to a level field then moves on to how their used (through a "global symbol" or directly passed in) and how they can "leak" if you're not careful.

To help protect you and your code from any kind of damage down the line, Troels suggests making a container to keep objects where they need to be. He even includes an example with namespace support to make things even easier down the road.

In the second, Felix demonstrates how, with some simple if logic, you can simulate dependencies. His examples include a simple if to check for the return of "true" from various functions and an inline example of an svn export and FTP.