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run code in 200+ php & hhvm versions
Bugs & Features
<?php $array = array("FFF" => '1',22,54,75,90,364); $keys = array_keys($array); Var_dump($keys);
based on QE4Iu
Output for 5.6.0 - 5.6.30, hhvm-3.15.4, 7.0.0 - 7.2.8
array(6) { [0]=> string(3) "FFF" [1]=> int(0) [2]=> int(1) [3]=> int(2) [4]=> int(3) [5]=> int(4) }