3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $ch="s1"; $_SESSION[$ch] = array(); $_SESSION[$ch][] .= 11; $_SESSION[$ch][] .= 22; var_dump($_SESSION);
Output for 4.3.0 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0
array(1) { ["s1"]=> array(2) { [0]=> string(2) "11" [1]=> string(2) "22" } }