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<?php class HelloWorld { readonly public string $say; public function __construct() { $this->say = 'Hello World'; } } class HelloNewWorld extends HelloWorld { public function __construct() { $this->say = 'Hello New World'; } } echo (new HelloWorld())->say; echo "<br>"; echo (new HelloNewWorld())->say;
Output for 8.4.1 - 8.4.12
Hello World<br>Hello New World
Output for 8.1.32, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25
Hello World<br> Fatal error: Uncaught Error: Cannot initialize readonly property HelloWorld::$say from scope HelloNewWorld in /in/VKmas:17 Stack trace: #0 /in/VKmas(23): HelloNewWorld->__construct() #1 {main} thrown in /in/VKmas on line 17
Process exited with code 255.
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