3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = [1,2,3]; $b = [a,b,c,d,]; if ( sizeof($a) && sizeof($b) ) { echo 'unbelievable'; }
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Fatal error: Uncaught Error: Undefined constant "a" in /in/7ChGW:4 Stack trace: #0 {main} thrown in /in/7ChGW on line 4
Process exited with code 255.
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Warning: Use of undefined constant a - assumed 'a' (this will throw an Error in a future version of PHP) in /in/7ChGW on line 4 Warning: Use of undefined constant b - assumed 'b' (this will throw an Error in a future version of PHP) in /in/7ChGW on line 4 Warning: Use of undefined constant c - assumed 'c' (this will throw an Error in a future version of PHP) in /in/7ChGW on line 4 Warning: Use of undefined constant d - assumed 'd' (this will throw an Error in a future version of PHP) in /in/7ChGW on line 4 unbelievable
Output for 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
Notice: Use of undefined constant a - assumed 'a' in /in/7ChGW on line 4 Notice: Use of undefined constant b - assumed 'b' in /in/7ChGW on line 4 Notice: Use of undefined constant c - assumed 'c' in /in/7ChGW on line 4 Notice: Use of undefined constant d - assumed 'd' in /in/7ChGW on line 4 unbelievable
preferences:
259.14 ms | 403 KiB | 376 Q