Backend PHP Modern Features

When to use this skill

• Using PHP 8.0+
• Modernizing codebase
• Type-safe code
• Leveraging new language features

Workflow

• ] Use enums for fixed sets of values
• ] Apply attributes for metadata
• ] Use readonly for immutable properties
• ] Leverage union types
• ] Use named arguments

Instructions

Enums (PHP 8.1+)

php
<?php

enum UserStatus: string
{
    case ACTIVE = 'active';
    case INACTIVE = 'inactive';
    case BANNED = 'banned';

    public function label(): string
    {
        return match($this) {
            self::ACTIVE => 'Active User',
            self::INACTIVE => 'Inactive',
            self::BANNED => 'Banned User'
        };
    }
}

// Usage
$user->status = UserStatus::ACTIVE;

Readonly Properties (PHP 8.1+)

php
<?php

class User
{
    public function __construct(
        public readonly int $id,
        public readonly string $email,
        public string $name
    ) {}
}

$user = new User(1, 'user@example.com', 'John');
// $user->id = 2; // Error: Cannot modify readonly property

Union Types (PHP 8.0+)

php
<?php

function processValue(int|float|string $value): int|float
{
    return is_string($value) ? (int)$value : $value;
}

Named Arguments (PHP 8.0+)

php
<?php

function createUser(
    string $name,
    string $email,
    bool $isActive = true
): User {
    // ...
}

// Usage
$user = createUser(
    email: 'user@example.com',
    name: 'John Doe'
);

Attributes (PHP 8.0+)

php
<?php

#[Attribute]
class Route
{
    public function __construct(
        public string $path,
        public string $method = 'GET'
    ) {}
}

class UserController
{
    #[Route('/api/users', 'GET')]
    public function index() {}
}

Match Expression (PHP 8.0+)

php
<?php

$message = match($status) {
    UserStatus::ACTIVE => 'User is active',
    UserStatus::INACTIVE => 'User is inactive',
    UserStatus::BANNED => 'User is banned',
    default => 'Unknown status'
};

Resources

• Use enums instead of constants
• Readonly for immutable data
• Match is stricter than switch