3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = ''; $b = NULL; $c = ' '; echo isset($a); echo "\r\n"; echo isset($b); echo "\r\n"; echo isset($c); echo "\r\n"; echo isset($d); echo "\r\n"; echo '--------------------------------------'; echo "\r\n"; echo empty($a); echo "\r\n"; echo empty($b); echo "\r\n"; echo empty($c); echo "\r\n"; echo empty($d); echo "\r\n";
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
1 1 -------------------------------------- 1 1 1
preferences:
249.13 ms | 406 KiB | 460 Q