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run code in 300+ PHP versions simultaneously
<?php function f($a = null, $b) { var_dump(['a' => $a, 'b' => $b]); } f('1', 'test');
Output for 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Deprecated: Optional parameter $a declared before required parameter $b is implicitly treated as a required parameter in /in/A4iS6 on line 3 array(2) { ["a"]=> string(1) "1" ["b"]=> string(4) "test" }
Output for 8.0.0 - 8.0.30
Deprecated: Required parameter $b follows optional parameter $a in /in/A4iS6 on line 3 array(2) { ["a"]=> string(1) "1" ["b"]=> string(4) "test" }
Output for 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33
array(2) { ["a"]=> string(1) "1" ["b"]=> string(4) "test" }
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
Parse error: syntax error, unexpected '[', expecting ')' in /in/A4iS6 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 '[', expecting ')' in /in/A4iS6 on line 5
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `')'' in /in/A4iS6 on line 5
Process exited with code 255.

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