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run code in 150+ php & hhvm versions
Bugs & Features
<?php $arr = array('key' => null); var_dump(isset($arr[$key]));
Output for 5.0.4 - 5.6.28, 7.0.0 - 7.1.0
Notice: Undefined variable: key in /in/p0DQ3 on line 4 bool(false)
Output for hhvm-3.10.0 - 3.12.0
bool(false)
Output for 4.3.0 - 5.0.3
Notice: Undefined variable: key in /in/p0DQ3 on line 4 bool(false)