<?php
 
$array = [
	'd' => [
		'f',
		'e',
	],
	'a' => [
		'c',
		'b',
	],
];
 
function recur_asort(&$array) {
   foreach ($array as &$value) {
      if (is_array($value)) recur_asort
($value);    }
}
 
recur_asort($array);
 
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