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<?php function createClass(array $val, array $vals) { return new class($val, $vals) { public function __construct(public array $val, public array $vals) { } }; } $x = []; $y = &$x[]; $y = []; $z = createClass($y, $x); $y[] = 'a'; var_dump($x, $z->val, $z->vals);
Output for 8.0.1 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
array(1) { [0]=> &array(1) { [0]=> string(1) "a" } } array(0) { } array(1) { [0]=> &array(1) { [0]=> string(1) "a" } }

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