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run code in 300+ PHP versions simultaneously
<?php $a = []; $a[1][] = 'test'; var_dump($a);
Output for 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.31, 8.2.0 - 8.2.27, 8.3.0 - 8.3.16, 8.4.1 - 8.4.3
array(1) { [1]=> array(1) { [0]=> string(4) "test" } }
preferences:
135.66 ms | 408 KiB | 5 Q