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<?php $a['p'] = null; $a['c'] = false; echo isset($a['p']); echo " __ "; echo array_key_exists($a['p']); echo " ___ "; echo isset($a['c']);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
__ Fatal error: Uncaught ArgumentCountError: array_key_exists() expects exactly 2 arguments, 1 given in /in/L8Q5S:9 Stack trace: #0 /in/L8Q5S(9): array_key_exists(NULL) #1 {main} thrown in /in/L8Q5S on line 9
Process exited with code 255.
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.38, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
__ Warning: array_key_exists() expects exactly 2 parameters, 1 given in /in/L8Q5S on line 9 ___ 1
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
__ Warning: Wrong parameter count for array_key_exists() in /in/L8Q5S on line 9 ___ 1

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