Property Hooks (PHP 8.4)

Also Known As

TL;DR

Explanation

Property hooks allow get and set logic inline: public string $name { get => strtoupper($this->name); set => $this->name = trim($value); }. The get hook runs when the property is read; set runs when it is assigned. A get-only hook makes the property effectively read-only to external code. This eliminates entire classes of getter/setter boilerplate while keeping the clean property-access syntax. Works with constructor promotion, interfaces, and abstract classes.

Common Misconception

Why It Matters

Common Mistakes

• Using both a hook and a traditional getter/setter for the same property — they conflict.
• Recursive get hooks — a get hook that reads $this->name triggers itself infinitely; use $this->name directly inside the hook.
• Set hooks that don't assign — if the set hook doesn't assign to the backing value, the value is never stored.
• Not understanding that a get-only hook prevents direct assignment from outside the class.

Code Examples

// PHP 8.3 — boilerplate getters/setters:
class User {
    private string $email;
    public function getEmail(): string { return strtolower($this->email); }
    public function setEmail(string $email): void {
        if (!filter_var($email, FILTER_VALIDATE_EMAIL)) throw new \InvalidArgumentException('Invalid email');
        $this->email = $email;
    }
}

// PHP 8.4 — property hooks:
class User {
    public string $email {
        get => strtolower($this->email);
        set {
            if (!filter_var($value, FILTER_VALIDATE_EMAIL)) {
                throw new \InvalidArgumentException('Invalid email');
            }
            $this->email = $value;
        }
    }
    // Usage: $user->email = 'Alice@EXAMPLE.COM'; echo $user->email; // alice@example.com
}

Tags

🧠 Logic Engine

References

• https://wiki.php.net/rfc/property-hooks