3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $array = array("person1" => array(0 => array('k1'=>'v1', 'k2'=>'v2'), 1 => array('k1'=>'v1', 'k2'=>'v2')), "person2" => array(0 => array('k1'=>'v1', 'k2'=>'v2'), 1 => array('k1'=>'v1', 'k2'=>'v2'))); $reset_key = reset($array); $first_key = key($array); echo $reset_key;
based on 16uQ3
Output for 5.4.0 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0
Notice: Array to string conversion in /in/8022v on line 5 Array
Output for 4.3.0 - 5.3.29
Array