<?php
function array_traverse (&$array, $function, $limit=2, $truncate=true) {
	foreach ($array as $key => &$value) {
		if (is_array($value)) {
			if ($limit > 0) {
				array_traverse($value, $function, --$limit, $truncate);
			} else {
				if ($truncate) {
					$value = '{truncated}';
				}
			}
		} else {
			$value = $function($value, $key);
		}
	}
}