3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a[3][10] = null; if(isset($a[3][10])) { echo 'Isset'; } else { echo 'No'; }
Output for 7.3.0 - 7.3.29, 7.4.0 - 7.4.21, 8.0.0 - 8.0.8
No

preferences:
76.09 ms | 459 KiB | 5 Q