Online PHP editor | refs for dNbe8

<?php function machine_forget(&$data) { $data = null; } $answer = 90; var_dump((string)$answer); machine_forget($answer); var_dump((string)$answer); // shhh no spoilers class zombie { protected $val; public function __construct($val) { $this->val = $val; } public function __destruct() { $this->vessel = $this; } public function __toString() { return $this->val; } } $answer = new zombie("42"); $answer->vessel = &$answer; var_dump((string)$answer); machine_forget($answer); var_dump((string)$answer);