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run code in 150+ php & hhvm versions
Bugs & Features
<?php $params = array(); var_dump(explode(",", $params["key"]));
based on BWqBH
Output for 5.3.0 - 5.6.28, hhvm-3.10.0, 7.0.0 - 7.1.0
Notice: Undefined index: key in /in/REBuf on line 3 array(1) { [0]=> string(0) "" }
Output for hhvm-3.12.0 - 3.13.2
Notice: Undefined index: key in /in/REBuf on line 3 Warning: explode() expects parameter 2 to be string, null given in /in/REBuf on line 3 NULL
Output for 4.3.0 - 5.2.17
Notice: Undefined index: key in /in/REBuf on line 3 array(1) { [0]=> string(0) "" }