3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $array = [ 1 => [ 1 => [ 'anna', 'alice' ], 2 => [ 'bob', 'bartold' ] ], 2 => [ 1 => [ 'carol' ], 2 => [ 'david' ] ] ]; $result = []; $prevKey = 0; array_walk_recursive($array, function ($value, $key) use (&$result, &$prevKey) { if (!is_array($value)) { }else { $prevKey = $key; echo $key; } }); var_dump($result);
based on Vjqir
Output for 5.4.0 - 7.2.0
array(0) { }
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/2WEpY on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[' in /in/2WEpY on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/2WEpY on line 3
Process exited with code 255.