3v4l.org

run code in 300+ PHP versions simultaneously
<?php $upgradeKeys = array( 'featured-listing', 'basic-pack', 'designer-blog', 'power-pack' ); $_upgradeKeys = array_diff( $upgradeKeys, array( 'featured-listing', 'basic-pack', 'designer-blog', 'power-pack' ) ); $upgradeKeys = $_upgradeKeys; $upgradeKeys[] = 'power-pack'; print_r($upgradeKeys);
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.33, 5.5.0 - 5.5.17, 5.6.0, 7.0.0 - 7.0.31, 7.1.0 - 7.1.23, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Array ( [0] => power-pack )
Output for 5.4.34 - 5.4.45, 5.5.18 - 5.5.38, 5.6.1 - 5.6.38
Array ( [4] => power-pack )
preferences:
248.57 ms | 402 KiB | 414 Q