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<?php readonly class User { public function __construct( public int $id, public string $name ) {} } $user = new User(123, "Rasmus"); var_dump($user->id, $user->name); $user->id = 456; // error: Cannot modify readonly property User::$id
Output for 8.2.13 - 8.2.29, 8.3.5 - 8.3.26, 8.4.1 - 8.4.14
int(123) string(6) "Rasmus" Fatal error: Uncaught Error: Cannot modify readonly property User::$id in /in/DiV1A:14 Stack trace: #0 {main} thrown in /in/DiV1A on line 14
Process exited with code 255.
Output for 8.1.30 - 8.1.33
Parse error: syntax error, unexpected token "readonly", expecting end of file in /in/DiV1A on line 3
Process exited with code 255.
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