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<?php $s = new \WeakMap(); $a = new \stdClass(); $b = new \stdClass(); $s[$a] ??= []; $v = &$s[$a]; $v[1] = ['foo' => 'bar']; var_dump($v); var_dump($s[$a]); $d = &$s[$a][1]; $d['bar'] = 'baz'; var_dump($d); var_dump($s[$a]); $s[$b] ??= []; $s[$b][2] = 2; var_dump($s[$b]); var_dump($s); unset($a); var_dump($s);
Output for 8.1.32, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
array(1) { [1]=> array(1) { ["foo"]=> string(3) "bar" } } array(1) { [1]=> array(1) { ["foo"]=> string(3) "bar" } } array(2) { ["foo"]=> string(3) "bar" ["bar"]=> string(3) "baz" } array(1) { [1]=> &array(2) { ["foo"]=> string(3) "bar" ["bar"]=> string(3) "baz" } } array(1) { [2]=> int(2) } object(WeakMap)#1 (2) { [0]=> array(2) { ["key"]=> object(stdClass)#2 (0) { } ["value"]=> &array(1) { [1]=> &array(2) { ["foo"]=> string(3) "bar" ["bar"]=> string(3) "baz" } } } [1]=> array(2) { ["key"]=> object(stdClass)#3 (0) { } ["value"]=> array(1) { [2]=> int(2) } } } object(WeakMap)#1 (1) { [0]=> array(2) { ["key"]=> object(stdClass)#3 (0) { } ["value"]=> array(1) { [2]=> int(2) } } }
preferences:
58.94 ms | 409 KiB | 5 Q