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<?php $a = array('a' => array(0 => 1, 1 => 2) ,'b' => array(0 => 3, 1 => 4)); print_r(array_reduce($a, 'array_merge', $a));
Output for 4.3.0 - 4.3.9, 5.0.0 - 5.0.2, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.12 - 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 ( [a] => Array ( [0] => 1 [1] => 2 ) [b] => Array ( [0] => 3 [1] => 4 ) [0] => 1 [1] => 2 [2] => 3 [3] => 4 )
Output for 5.0.3 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Warning: array_merge(): Argument #1 is not an array in /in/ki2oR on line 3 Warning: array_merge(): Argument #1 is not an array in /in/ki2oR on line 3
Output for 4.3.10 - 4.3.11, 4.4.0 - 4.4.9
Array ( [0] => 1 [1] => 1 [2] => 2 [3] => 3 [4] => 4 )

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