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run code in 500+ PHP versions simultaneously
<?php $arr = []; $arr[null] = 1; var_dump($arr); $arr = []; $arr[''] = 1; var_dump($arr);
Output for 8.5.0 - 8.5.3
Deprecated: Using null as an array offset is deprecated, use an empty string instead in /in/5TTAO on line 4 array(1) { [""]=> int(1) } array(1) { [""]=> int(1) }
Output for 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18
array(1) { [""]=> int(1) } array(1) { [""]=> int(1) }
preferences:
50.21 ms | 839 KiB | 4 Q