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<?php $a = null; print $a ?? 'b'; print "\n"; print $a ?: 'b'; print "\n"; print $c ?? 'a'; print "\n"; print $c ?: 'a'; print "\n"; $b = array('a' => null); print $b['a'] ?? 'd'; print "\n"; print $b['a'] ?: 'd'; print "\n"; print $b['c'] ?? 'e'; print "\n"; print $b['c'] ?: 'e'; print "\n";
Output for 8.0.0 - 8.0.19, 8.1.0 - 8.1.6
b b a Warning: Undefined variable $c in /in/McavC on line 14 a d d e Warning: Undefined array key "c" in /in/McavC on line 28 e
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 - 7.4.29
b b a Notice: Undefined variable: c in /in/McavC on line 14 a d d e Notice: Undefined index: c in /in/McavC on line 28 e
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 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/McavC on line 5
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '?' in /in/McavC on line 5
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/McavC on line 5
Process exited with code 255.

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