3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $a1=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow"); $a2=array("e"=>"red","f"=>"green","g"=>"blue"); var_dump(array_intersect(array_keys($a1), array_keys($a2)));
Output for 4.3.0 - 7.2.0
array(0) { }