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<?php declare(strict_types=1); function testParam(?string $arg = null){ var_dump($arg); } testParam(null); testParam("hi"); testParam();
Output for 7.1.0 - 7.1.25, 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 - 8.3.7
NULL string(2) "hi" NULL
Output for 7.0.0 - 7.0.20
Parse error: syntax error, unexpected '?', expecting variable (T_VARIABLE) in /in/OlWg5 on line 5
Process exited with code 255.
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158.08 ms | 401 KiB | 189 Q