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run code in 300+ PHP versions simultaneously
<?php $array = ['a', 'b']; usort($array, function ($firstValue, $secondValue) { echo "COMPARING: {$firstValue} with {$secondValue}\n"; return -1;});
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 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 - 8.3.15, 8.4.1 - 8.4.2
COMPARING: a with b
Output for 5.6.0 - 5.6.40
COMPARING: b with a
preferences:
132.41 ms | 406 KiB | 5 Q