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<?php $foo = [ 'a' => '1', 'b' => '1', 'c' => '2', ]; function change_keys($array, $callback) { $temp = array_map($callback, array_combine(array_keys($array), array_keys($array))); return array_combine($temp, $array); } var_dump(change_keys($foo, function($v) { return '#' . $v; }));
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 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(3) { ["#a"]=> string(1) "1" ["#b"]=> string(1) "1" ["#c"]=> string(1) "2" }
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/V7rpL on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[' in /in/V7rpL on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/V7rpL on line 3
Process exited with code 255.
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239.56 ms | 401 KiB | 356 Q