3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $arr['M3'] ='M3'; $wat = $arr + array("J4"=>"J4"); var_dump($wat);
Output for 4.3.0 - 7.2.0
array(2) { ["M3"]=> string(2) "M3" ["J4"]=> string(2) "J4" }