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<?php $arr = [ 1 => ["key" => "a"], 2 => ["key" => "b"] ]; foreach ($arr as $key => $val) { $arr[$val["key"]] = $val; unset($arr[$key]); } var_dump($arr);
Output for 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 - 8.1.31, 8.2.0 - 8.2.27, 8.3.0 - 8.3.15, 8.4.1 - 8.4.2
array(2) { ["a"]=> array(1) { ["key"]=> string(1) "a" } ["b"]=> array(1) { ["key"]=> string(1) "b" } }
preferences:
131.3 ms | 408 KiB | 5 Q