Classes e Herança em PHP

<?php

class User {
    private string $name;
    private int $age;

    public function __construct(string $name, int $age) {
        $this->name = $name;
        $this->age = $age;
    }

    public function getName(): string {
        return $this->name;
    }

    public function isAdult(): bool {
        return $this->age >= 18;
    }
}

// Inheritance
class Admin extends User {
    private array $permissions = [];

    public function grant(string $perm): void {
        $this->permissions[] = $perm;
    }
}

$admin = new Admin("Alice", 30);
$admin->grant("delete");
echo $admin->getName();   // Alice
echo $admin->isAdult();   // 1 (true)