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run code in 300+ PHP versions simultaneously
<?php $num = ' '; if (isset(trim($num))) { echo 'true'; } else { echo 'false'; }
Output for 5.3.0 - 5.3.28, 5.4.0 - 5.4.30
Fatal error: Can't use function return value in write context in /in/Eir9p on line 5
Process exited with code 255.
preferences:
178.44 ms | 1395 KiB | 67 Q