PHP 8.1 Demo Code

This code demonstrates various PHP 8.0 and 8.1 features in a realistic, functional (but incomplete) codebase. The code is part of some DNS validation logic.

This code came from a code along session in the October 2021 Arizona PHP User Group meetup, and was inspired by some refactoring work I was doing at my day job.

Feature Sightings

• Enums
• Throw exceptions as an expression
• Constructor property promotion
• Readonly properties
• Union types
• static return type
• First class callables
• new in initializers
• match expressions
• Trailing commas in parameter lists
• catch exceptions without a variable

Running the Code

Requirements

• Docker
• PHP
• Composer

Instructions

1. Uncomment lines 10 and 11 in index.php.
   • This is because you are running Composer locally, and not in the container, so the current version of Composer you have will not include the enums in with the autoloader.
2. Run composer run shell to download the php 8.1 image and boot up a docker container for it with a shell.
3. Run php index.php within the container's shell to execute this file.
4. Run exit to exit and shutdown the container.

Resources

• https://stitcher.io/blog/new-in-php-81
• https://www.php.net/manual/en/migration80.php
• https://hub.docker.com/r/phpdaily/php