3v4l.org

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<?php $array = array(5612 => 'my note'); $keys = array_keys($array); print_r($keys[0][]); ?>
Output for 5.3.0 - 5.3.28, 5.4.0 - 5.4.30
Fatal error: Cannot use [] for reading in /in/P264k on line 5
Process exited with code 255.
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201.88 ms | 1395 KiB | 67 Q