3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = 3; $b = 4; list($b, $a) = [ $a, $b]; echo "a=$a b=$b\n";
Output for 7.1.25 - 7.1.32, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.30, 8.0.0 - 8.0.20, 8.1.0 - 8.1.7
a=4 b=3
preferences:
31.95 ms | 409 KiB | 5 Q