3v4l.org

run code in 300+ PHP versions simultaneously
<?php class m { private $actual_fields_are_here; function __construct(){ $this->actual_fields_are_here = new stdclass; } public function __set($name, $val){ $this->actual_fields_are_here->{$name} = $val; } public function __get($name){ return $this->actual_fields_are_here->{$name}; } public function __isset($name){ return isset($this->actual_fields_are_here->{$name}); } public function __unset($name){ return isset($this->actual_fields_are_here->{$name}); } public function __debugInfo(){ return (array)$this->actual_fields_are_here; } } $m = new m; $m->c = 'Hey'; var_dump($m);
Output for 5.6.0 - 5.6.29, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
object(m)#1 (1) { ["c"]=> string(3) "Hey" }

preferences:
131.67 ms | 404 KiB | 239 Q