3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = [1, [2, 3]]; $array[1][1] = &$array; json_encode($array); echo json_last_error_msg() . ', ' . json_last_error ();
Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.30, 8.2.0 - 8.2.25, 8.3.0 - 8.3.13
Recursion detected, 6
preferences:
85.2 ms | 406 KiB | 5 Q