3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array1 = array( 'A' => 10, 'B' => 20, 'C' => 30, 'D' => 40 ); $array2 = array( '0' => A, '1' => B, ); print_r(array_diff($array2, array_flip($array1)));
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/mmH7L:10 Stack trace: #0 {main} thrown in /in/mmH7L on line 10
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/mmH7L on line 10 Warning: Use of undefined constant B - assumed 'B' (this will throw an Error in a future version of PHP) in /in/mmH7L on line 11 Array ( )
Output for 5.4.1 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.21, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33
Notice: Use of undefined constant A - assumed 'A' in /in/mmH7L on line 10 Notice: Use of undefined constant B - assumed 'B' in /in/mmH7L on line 11 Array ( )
preferences:
190.96 ms | 403 KiB | 258 Q