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<?php $a = ['x' => 5]; $b = ['y' => 7]; print_r($a + $b); $a = [1,2]; $b = [3,4]; print_r($a + $b);
Output for 7.1.25 - 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
Array ( [x] => 5 [y] => 7 ) Array ( [0] => 1 [1] => 2 )

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