3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr = array ( 0 => 'nested array', 1 => 'nested array', 2 => 'nested array', 3 => 'nested array', 6 => 'nested array', 7 => 'nested array', ); var_dump(key(array_diff(array_keys(array_values($arr)), array_keys($arr))));
Output for git.master, git.master_jit, rfc.property-hooks
int(4)

This tab shows result from various feature-branches currently under review by the php developers. Contact me to have additional branches featured.

Active branches

Archived branches

Once feature-branches are merged or declined, they are no longer available. Their functionality (when merged) can be viewed from the main output page

preferences:
42 ms | 401 KiB | 8 Q