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<?php class Foo { readonly int $foo; public function __construct() { $this->foo = 42; } public function unset_me() { unset( $this->foo ); } public function __set($key, $value) { echo "__set called with {$value}\n"; } } $f = new Foo; $f->unset_me(); $f->foo = 43;
Output for 8.1.13 - 8.1.34, 8.2.22 - 8.2.30, 8.3.5 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
Fatal error: Uncaught Error: Cannot unset readonly property Foo::$foo in /in/Rj4np:12 Stack trace: #0 /in/Rj4np(22): Foo->unset_me() #1 {main} thrown in /in/Rj4np on line 12
Process exited with code 255.

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