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<?php $arr = ['a' => 1]; $arr['b'] = &$arr['a']; var_dump($arr); $arr['b'] = 'xiami'; var_dump($arr);
Output for 5.6.38, 7.0.0 - 7.0.33, 7.1.0 - 7.1.25, 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
array(2) { ["a"]=> &int(1) ["b"]=> &int(1) } array(2) { ["a"]=> &string(5) "xiami" ["b"]=> &string(5) "xiami" }
preferences:
141.66 ms | 408 KiB | 5 Q