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<?php class Foo { public function __construct( public readonly int $foo ) { } } $f = new Foo(3); $f->foo = 5;
Output for 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
Fatal error: Uncaught Error: Cannot modify readonly property Foo::$foo in /in/nqgpL:10 Stack trace: #0 {main} thrown in /in/nqgpL on line 10
Process exited with code 255.
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