3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = null; print $a ?? 'b'; print $a ?: 'b'; print $c ?? 'a'; print $c ?: 'a';
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
bba Warning: Undefined variable $c in /in/QvC9H on line 9 a
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.6 - 7.2.33, 7.3.16 - 7.3.31, 7.4.0 - 7.4.33
bba Notice: Undefined variable: c in /in/QvC9H on line 9 a
Output for 7.3.32 - 7.3.33
bbaa
Output for 5.5.24 - 5.5.35, 5.6.8 - 5.6.28
Parse error: syntax error, unexpected '?' in /in/QvC9H on line 5
Process exited with code 255.
preferences:
152.39 ms | 402 KiB | 182 Q