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run code in 200+ php & hhvm versions
Bugs & Features
<?php $a = false; if (isset($a)) {echo "true";} else {echo "false";} //echoes true
Output for 4.3.0 - 5.0.5, 5.1.1 - 7.2.0
true
Output for 5.1.0
Fatal error: fatal flex scanner internal error--end of buffer missed in /in/rG2DW on line 4
Process exited with code 255.