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run code in 500+ PHP versions simultaneously
<?php class x { private array $config = array(); function __isset($name) { print __METHOD__." ".$name.PHP_EOL; return isset($this->config[$name]); } function __get($name) { print __METHOD__." ".$name.PHP_EOL; return 'a'; } } $x = new x; var_dump(isset($x->a)); var_dump(empty($x->a));

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