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<?php $k = (string)"0"; $a = array( 'name' => 'a', $k => 'null' ); $b = array( 'name' => 'b', $k => 'zero' ); $c = array( $k => 'zeronull', 'name' => 'c' ); var_dump($a); var_dump($b); var_dump($c); var_dump(array_merge($a, $b)); var_dump($a + $b); var_dump(array_merge($a, $c)); var_dump($a + $c); var_dump(array_merge($a, $b, $c)); var_dump($a + $b + $c);
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
array(2) { ["name"]=> string(1) "a" [0]=> string(4) "null" } array(2) { ["name"]=> string(1) "b" [0]=> string(4) "zero" } array(2) { [0]=> string(8) "zeronull" ["name"]=> string(1) "c" } array(3) { ["name"]=> string(1) "b" [0]=> string(4) "null" [1]=> string(4) "zero" } array(2) { ["name"]=> string(1) "a" [0]=> string(4) "null" } array(3) { ["name"]=> string(1) "c" [0]=> string(4) "null" [1]=> string(8) "zeronull" } array(2) { ["name"]=> string(1) "a" [0]=> string(4) "null" } array(4) { ["name"]=> string(1) "c" [0]=> string(4) "null" [1]=> string(4) "zero" [2]=> string(8) "zeronull" } array(2) { ["name"]=> string(1) "a" [0]=> string(4) "null" }

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