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<?php $array = [1 => 'a', 0 => 'b']; var_dump(array_is_list($array)); ksort($array); var_dump(array_is_list($array)); $array = [1 => 'b']; $array[0] = 'a'; var_dump(array_is_list($array)); asort($array); // lucky sort var_dump(array_is_list($array));
Output for 8.5.7
bool(false) bool(true) bool(false) bool(true)

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