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run code in 300+ PHP versions simultaneously
<?php [$key => $value] = ['b'=> 2]; var_dump($key); var_dump($value);
Output for 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
Warning: Undefined variable $key in /in/5ubJU on line 5 Warning: Undefined array key "" in /in/5ubJU on line 5 Warning: Undefined variable $key in /in/5ubJU on line 7 NULL NULL
preferences:
64.98 ms | 406 KiB | 5 Q