3v4l.org

run code in 300+ PHP versions simultaneously
<?php ///on php version < 8.4 class Foo { private $data = null; public function issetData(){ return $this->data !== null; } public function setData($data){ $this->data = $data; } } $foo = new Foo(); var_dump($foo->issetData()); $foo->setData(123); var_dump($foo->issetData());
Output for 8.1.32, 8.2.26 - 8.2.29, 8.3.5 - 8.3.25, 8.4.1 - 8.4.12
bool(false) bool(true)

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