3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = null; $b = false; $c = $b ?: '1'; $d = $a ?? '2'; echo $c; echo $d;
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
12
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
Parse error: syntax error, unexpected '?' in /in/u2JuL on line 5
Process exited with code 255.
preferences:
276.24 ms | 402 KiB | 376 Q