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run code in 150+ php & hhvm versions
Bugs & Features
<?php $val = 'a'; var_dump(array_merge((array) $val, null));
based on ocZCD
Output for 5.0.0 - 7.1.0
Warning: array_merge(): Argument #2 is not an array in /in/PARrI on line 3 NULL
Output for 4.3.0 - 4.4.9
array(1) { [0]=> string(1) "a" }