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run code in 300+ PHP versions simultaneously
<?php class A { public stdClass $prop; public function __set($x, $y) { echo "SET\n"; $this->$x = $y; } } $a = new A(); $a->prop = new stdClass; var_dump($a); $a->undeclared = new stdClass; var_dump($a); $a->prop = new stdClass; var_dump($a);

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24.73 ms | 404 KiB | 5 Q