3v4l.org

run code in 300+ PHP versions simultaneously
<?php $MAP = [ ['x', 'x', 'x', 'x'], ['x', 's', 'p', 'x'], ['x', 'p', 'p', 'x'], ['x', 'p', 'p', 'x'], ['x', 'p', 'p', 'x'], ['x', 'p', 'p', 'x'], ['x', 'x', 'x', 'x'], ]; $iterator = new RecursiveIteratorIterator(new RecursiveArrayIterator($MAP), RecursiveIteratorIterator::SELF_FIRST); $parentKey = null; foreach($iterator as $key => $value) { if (is_scalar($value)) { var_dump($parentKey.'/'.$key.' => '.$value); } else { $parentKey = $key; } }
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
string(8) "0/0 => x" string(8) "0/1 => x" string(8) "0/2 => x" string(8) "0/3 => x" string(8) "1/0 => x" string(8) "1/1 => s" string(8) "1/2 => p" string(8) "1/3 => x" string(8) "2/0 => x" string(8) "2/1 => p" string(8) "2/2 => p" string(8) "2/3 => x" string(8) "3/0 => x" string(8) "3/1 => p" string(8) "3/2 => p" string(8) "3/3 => x" string(8) "4/0 => x" string(8) "4/1 => p" string(8) "4/2 => p" string(8) "4/3 => x" string(8) "5/0 => x" string(8) "5/1 => p" string(8) "5/2 => p" string(8) "5/3 => x" string(8) "6/0 => x" string(8) "6/1 => x" string(8) "6/2 => x" string(8) "6/3 => x"

preferences:
96.51 ms | 2317 KiB | 4 Q