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run code in 300+ PHP versions simultaneously
<?php $array = ['foo'=>1, 'bar'=>2]; foreach($array as $k=>&$v) { $array['bernard']=3; echo key($v); }
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
Fatal error: Uncaught TypeError: key(): Argument #1 ($array) must be of type array, int given in /in/0B4UF:7 Stack trace: #0 /in/0B4UF(7): key(1) #1 {main} thrown in /in/0B4UF on line 7
Process exited with code 255.
Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Warning: key() expects parameter 1 to be array, int given in /in/0B4UF on line 7 Warning: key() expects parameter 1 to be array, int given in /in/0B4UF on line 7 Warning: key() expects parameter 1 to be array, int given in /in/0B4UF on line 7
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33
Warning: key() expects parameter 1 to be array, integer given in /in/0B4UF on line 7 Warning: key() expects parameter 1 to be array, integer given in /in/0B4UF on line 7 Warning: key() expects parameter 1 to be array, integer given in /in/0B4UF on line 7
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 '[' in /in/0B4UF on line 3
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/0B4UF on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/0B4UF on line 3
Process exited with code 255.

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