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<?php class Increment { function __invoke($x) { ++$x->num; } } $c = new Increment(); $a = new \stdClass(); $a->num = 5; call_user_func_array($c, [$a]); var_dump($a);
Output for 5.6.0 - 5.6.25, 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 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
object(stdClass)#2 (1) { ["num"]=> int(6) }

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