Getting Started with PHP 8.3

PHP 8.3 brings exciting new features and improvements that make the language more powerful and developer-friendly. In this comprehensive tutorial, we'll explore the key additions and how to use them in your projects.

What's New in PHP 8.3?

1. Typed Class Constants

One of the most anticipated features is the ability to add type declarations to class constants:

php

1class Status {
2    public const string PENDING = 'pending';
3    public const string APPROVED = 'approved';
4    public const string REJECTED = 'rejected';
5}

This provides better type safety and makes your code more self-documenting.

2. Dynamic Class Constant Fetch

You can now fetch class constants dynamically using variables:

php

1class Config {
2    public const string APP_NAME = 'MyApp';
3    public const string APP_VERSION = '1.0.0';
4}
5
6$constantName = 'APP_NAME';
7echo Config::{$constantName}; // Outputs: MyApp

3. #[Override] Attribute

The new #[Override] attribute helps prevent bugs by ensuring a method actually overrides a parent method:

php

1class ParentClass {
2    public function process(): void {
3        // Implementation
4    }
5}
6
7class ChildClass extends ParentClass {
8    #[Override]
9    public function process(): void {
10        // This will work fine
11    }
12}

Setting Up PHP 8.3

Installation on Ubuntu/Debian

bash

1sudo add-apt-repository ppa:ondrej/php
2sudo apt update
3sudo apt install php8.3

Installation on macOS

bash

1brew install php@8.3
2brew link php@8.3

Practical Example: Building a User Service

php

1<?php
2declare(strict_types=1);
3
4namespace App\Services;
5
6enum UserStatus: string {
7    case ACTIVE = 'active';
8    case INACTIVE = 'inactive';
9    case SUSPENDED = 'suspended';
10}
11
12class UserService {
13    public const string DEFAULT_ROLE = 'user';
14    
15    public function __construct(
16        private readonly Database $db
17    ) {}
18    
19    public function create(array $data): User {
20        $user = new User(
21            email: $data['email'],
22            name: $data['name'],
23            status: UserStatus::ACTIVE,
24            role: self::DEFAULT_ROLE
25        );
26        
27        $this->db->save($user);
28        return $user;
29    }
30}

Conclusion

PHP 8.3 continues the language's evolution toward better type safety, developer experience, and performance. Start experimenting with these features in your projects today!