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<?php $arr1 = ['p' => 2, 'pm' => 1]; $arr2 = ['p' => '']; print_r(array_merge($arr1, $arr2));
Output for 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 - 8.1.30, 8.2.0 - 8.2.25, 8.3.0 - 8.3.13
Array ( [p] => [pm] => 1 )

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75.07 ms | 407 KiB | 5 Q