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run code in 150+ php & hhvm versions
Bugs & Features
<?php $i = 0; $arr = array(); $arr[$i] = ++$i; var_dump($arr);
Output for 5.1.0 - 7.1.0
array(1) { [1]=> int(1) }
Output for 4.3.0 - 5.0.5
array(1) { [0]=> int(1) }