3v4l.org

run code in 300+ PHP versions simultaneously
<?php $foo = [ 'a' => '1', 'b' => '1', 'c' => '2', ]; $bar = array_map(function($v) { return '#' . $v; }, array_combine(array_keys($foo), array_keys($foo))); $foo_new = array_combine($bar, $bar); var_dump($foo_new);

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37.5 ms | 402 KiB | 5 Q