3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr1 = ['a', 'b']; $arr2 = ['c', 'd']; array_push($arr1, ...$arr2); var_export($arr1);
Output for 7.4.20, 8.0.1 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
array ( 0 => 'a', 1 => 'b', 2 => 'c', 3 => 'd', )

preferences:
117.28 ms | 402 KiB | 86 Q