3v4l.org

run code in 300+ PHP versions simultaneously
<?php $foo=''; $foo[]='test'; print_r($foo);
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.29, 8.2.0 - 8.2.20, 8.3.0 - 8.3.8
Fatal error: Uncaught Error: [] operator not supported for strings in /in/AtO34:4 Stack trace: #0 {main} thrown in /in/AtO34 on line 4
Process exited with code 255.

preferences:
182.58 ms | 404 KiB | 228 Q