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<?php var_dump(array_unshift(array('key'=>'val'), array(0=>array('key1'=>'val1'), 1=>array('key2'=>'val2'))));
Output for 8.3.0 - 8.3.6
Fatal error: Uncaught Error: array_unshift(): Argument #1 ($array) could not be passed by reference in /in/GHf0j:2 Stack trace: #0 {main} thrown in /in/GHf0j on line 2
Process exited with code 255.
Output for 8.1.23 - 8.1.28, 8.2.10 - 8.2.18
Fatal error: Uncaught Error: array_unshift(): Argument #1 ($array) cannot be passed by reference in /in/GHf0j:2 Stack trace: #0 {main} thrown in /in/GHf0j on line 2
Process exited with code 255.
Output for 4.3.2 - 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, 5.3.0 - 5.3.28, 5.4.0 - 5.4.28
Fatal error: Only variables can be passed by reference in /in/GHf0j on line 2
Process exited with code 255.
Output for 4.3.0 - 4.3.1
Fatal error: Only variables can be passed by reference in /in/GHf0j on line 2

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139.54 ms | 401 KiB | 138 Q