3v4l.org

run code in 300+ PHP versions simultaneously
<?php var_dump(isset('foo')); var_dump(isset('')); var_dump(isset(null)); var_dump(isset(0)); var_dump(isset(1));
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.7
Fatal error: Cannot use isset() on the result of an expression (you can use "null !== expression" instead) in /in/Gmuec on line 3
Process exited with code 255.

preferences:
172.75 ms | 1395 KiB | 36 Q