PHP8 的重要特性揭示，助力你的代码更上一层楼

function calculateSum(int $a, int $b): int {
    return $a + $b;
}

$result = calculateSum(10, 20);
echo $result; // 输出30

// 在php.ini中启用JIT编译器
opcache.enable = 1
opcache.enable_cli = 1
opcache.jit_buffer_size = 100M
opcache.jit = 1205

echo "Hello, World!";

try {
    // 可能会抛出异常的代码块
    throw new Exception("Something went wrong!");
} catch (Exception $e) {
    // 捕获异常并进行处理
    echo "Error: " . $e->getMessage();
}

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

$user = new User("John", 30);
echo $user->username; // 输出 "John"
echo $user->age; // 输出 30

interface Logger {
    public function log(string $message): void;
}

function logMessage(Logger $logger, string $message): void {
    $logger->log($message);
}

$log = new class implements Logger {
    public function log(string $message): void {
        echo $message;
    }
};

logMessage($log, "Hello, World!"); // 输出 "Hello, World!"