3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $array = array( 0 => array('user_id' => '1', 'email'=>'email1'), 1 => array('user_id' => '2', 'email'=>'email2'), 2 => array('user_id' => '3', 'email'=>'email3') ); //var_dump(array_flip($array));
Output for 5.3.0 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0