the purpose is too specific I won't add a detailed explanation here

format_tree_text.php

<?php
// temporary explanation:
// $menu_href is a multi-dimensional array with depth levels for each item as values
// $menu_name is a multi-dimensional array with names for each item as values
// Yes these are not so effective ways to contain list datas. Terrible, actually.
// @@ gets the link, ## gets the content, $$ gets the contents under it (if there is)
$sub_menu_format = array(
	array(
		'',
		"<li class='sub'>\n"."$$\n"."</li>\n",
		''
	),
	array(
		"<ul class='menu'>\n",
		"<li>\n"."<a href='inner.php?sMenu=@@'>\n##</a>\n"."$$"."</li>\n",
		"</ul>"
	),
	array(
		"<ul>\n",
		"<li>\n"."<a href='inner.php?sMenu=@@'>\n##</a>\n"."$$"."</li>\n",
		"</ul>\n"
	),
	array(
		"<ul>\n",
		"<li>\n"."<a href='inner.php?sMenu=@@'>\n##</a>\n"."$$"."</li>\n",
		"</ul>"
	)
);
$sub_menu = function(
	$menu_href, $menu_name, $format, $content_indicator
) {
	$attempt = 0;
	reset($menu_href);
	reset($menu_name);

	$make = function(&$menu_href, &$menu_name, $level = 0) use (
		&$make, &$attempt,
		$format, &$content_indicator
	) {
		reset($menu_href);
		reset($menu_name);
		$html = '';

		$html .= str_repeat("\t", $level).$format[$level][0];
		while(key($menu_name) !== null && $attempt <= 50) {
			$attempt++;
			$last_line = str_repeat("\t", $level).$format[$level][1];

			if(is_array(current($menu_name))) {
				$sub_menu_href = current($menu_href);
				$sub_menu_name = current($menu_name);
				$last_line = str_replace(
					$content_indicator,
					array(
						key($menu_href),
						key($menu_name),
						$make($sub_menu_href, $sub_menu_name, $level + 1)
					),
					$last_line
				);
			} else {
				$last_line = str_replace(
					array($content_indicator[0], $content_indicator[1]),
					array(
						current($menu_href),
						current($menu_name)."\n"
					),
					$last_line
				);
			}

			$last_line = str_replace($content_indicator, '', $last_line);
			$html .= $last_line;
			next($menu_href);
			next($menu_name);
		}
		$html .= str_repeat("\t", $level).$format[$level][2];

		return $html;
	};

	return $make($menu_href, $menu_name);
};