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run code in 200+ php & hhvm versions
Bugs & Features
<?php $array[0]['d'] = 'd1'; $array[0]['a'] = 'a1'; $array[1]['d'] = 'd2'; $array[1]['a'] = 'a2'; $array[2]['d'] = 'd3'; $array[2]['a'] = 'a3'; $array[3]['d'] = 'd1'; $array[3]['a'] = 'a1'; $keys = array_keys($array,"a"); print_r($keys); ?>
based on DAcBW
Output for 5.6.0 - 5.6.30, hhvm-3.15.4, 7.0.0 - 7.2.0
Array ( )