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<?php $a = NULL; $c = ''; print $a ?? '1b'; print "\n"; print $a ?: '2b'; print "\n"; print $c ?? '1d'; print "\n"; print $c ?: '2d'; print "\n"; print $e ?? '1f'; print "\n"; print $e ?: '2f';
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.30, 8.2.0 - 8.2.25, 8.3.0 - 8.3.14
1b 2b 2d 1f Warning: Undefined variable $e in /in/ZBAa1 on line 21 2f
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
1b 2b 2d 1f Notice: Undefined variable: e in /in/ZBAa1 on line 21 2f
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
Parse error: syntax error, unexpected '?' in /in/ZBAa1 on line 6
Process exited with code 255.
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64.32 ms | 408 KiB | 5 Q