3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $domain_markets = [ 'AU' => 'sensasiaweb.itravelsoftware.com', 'UK' => 'sensasiaweb.itravelsoftware.com', 'US' => 'sensasiaweb.itravelsoftware.com', 'ES' => 'sensasiaweb.itravelsoftware.com', 'DE' => 'sensasiaweb-de.itravelsoftware.com', 'FR' => 'sensasiaweb-fr.itravelsoftware.com' ]; var_dump(array_keys($domain_markets), 'sensasiaweb.itravelsoftware.com', true);
based on B2RpM
Output for 5.6.0 - 7.2.8
array(6) { [0]=> string(2) "AU" [1]=> string(2) "UK" [2]=> string(2) "US" [3]=> string(2) "ES" [4]=> string(2) "DE" [5]=> string(2) "FR" } string(31) "sensasiaweb.itravelsoftware.com" bool(true)