The SitePoint PHP blog has posted another tutorial from author Christopher Pitt sharing another one of his "interesting things" you can do with PHP. In this latest article Christopher returns to the idea of "macros" to help with some pre-processing in PHP applications and, ultimately, creating a new language feature without some of the usual overhead.
Let’s have a bit of fun. A while ago, I experimented with PHP macros, adding Python range syntax. Then, the talented SaraMG mentioned an RFC, and LordKabelo suggested instead adding C#-style getters and setters to PHP.
Aware of how painfully slow it can be for an outsider to suggest and implement a new language feature, I took to my editor…
He starts with a brief refresher on macros to do some pre-processing on PHP scripts and allow you to make custom language features that then get interpreted into valid PHP (often with some interesting eval tricks involved). He starts by building a "base" to add in the C# style getters and setters in a special format inside of a class. He includes the macro definitions to set this up and the result once it is passed through the "yay" precompiler. To get around having to run that precompiler every time manually, he creates a custom autoloader to do the job dynamically. He then takes this logic and packages it up so it can be easily installed as a Composer dependency. With this structure in place, he moves on to the creation of a new language feature - the actual functionality for the getter/setters. He ends the post with a screen capture showing the language feature in use and some of the interesting things you can do with it.