3v4l.org

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<?php $hash = ['a' => 1, 'b' => 2]; print_r(array_map(function($v, $k) { return "$k: $v";}, $hash, array_keys($hash) )); ?>
Output for 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.21, 8.5.0 - 8.5.6
Array ( [0] => a: 1 [1] => b: 2 )
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34.68 ms | 850 KiB | 4 Q