Nested tree list (recursive)

nested_list

<?php 
// http://stackoverflow.com/questions/8020947/how-to-obtain-a-nested-html-list-from-objects-array-recordset
function render_tree($tree)
{
	echo '<ul>';
		foreach ($tree as $node)
		{
			render_node($node);
		}
	echo '</ul>';
}

function render_node($node, $level = 0)
{
	$inset = str_repeat('    ', $level);
	echo $inset, '<li style="border:1px solid #eee;">', $node->name;
	if (isset($node->children))
	{
		echo $inset, '<ul>';
		foreach ($node->children as $node)
		{
			render_node($node, $level+1);
		}
		echo $inset, '</ul>', $inset;
	}
	echo '</li>';
}

?>

<?php if ( ! empty($categories)): ?>
	<div class="row">
		<?php render_tree($categories); ?>
	</div>
<?php endif; ?>


$categories
Array
(
    [1] => stdClass Object
        (
            [id] => 1
            [company_id] => 1
            [name] => Boys
            [slug] => boys
            [parent_id] => 
            [depth] => 0
            [lft] => 1
            [rgt] => 14
            [is_enabled] => 1
            [image_url] => boys.jpeg
            [date_created] => 2012-04-17 16:16:59
            [date_modified] => 2014-09-03 18:20:50
            [order] => 2.00
            [children] => Array
                (
                    [28] => stdClass Object
                        (
                            [id] => 28
                            [company_id] => 1
                            [name] => legos
                            [slug] => legos
                            [parent_id] => 1
                            [depth] => 1
                            [lft] => 4
                            [rgt] => 5
                            [is_enabled] => 1
                            [image_url] => legos48.jpg
                            [date_created] => 2014-08-25 20:43:23
                            [date_modified] => 2014-08-25 20:43:23
                            [order] => 
                            [children] => Array
                                (
                                )

                        )

                    [29] => stdClass Object
                        (
                            [id] => 29
                            [company_id] => 1
                            [name] => blocks
                            [slug] => blocks
                            [parent_id] => 1
                            [depth] => 1
                            [lft] => 6
                            [rgt] => 11
                            [is_enabled] => 1
                            [image_url] => building_blocks22.jpg
                            [date_created] => 2014-09-02 16:34:12
                            [date_modified] => 2014-09-02 16:34:12
                            [order] => 
                            [children] => Array
                                (
                                    [30] => stdClass Object
                                        (
                                            [id] => 30
                                            [company_id] => 1
                                            [name] => fish
                                            [slug] => fish
                                            [parent_id] => 29
                                            [depth] => 2
                                            [lft] => 7
                                            [rgt] => 8
                                            [is_enabled] => 1
                                            [image_url] => fish.jpg
                                            [date_created] => 2014-09-02 16:35:52
                                            [date_modified] => 2014-09-04 19:59:58
                                            [order] => 
                                            [children] => Array
                                                (
                                                )

                                        )

                                )

                        )

                )

        )

    [2] => stdClass Object
        (
            [id] => 2
            [company_id] => 1
            [name] => Girls
            [slug] => girls
            [parent_id] => 
            [depth] => 0
            [lft] => 15
            [rgt] => 16
            [is_enabled] => 1
            [image_url] => girls.jpg
            [date_created] => 2012-04-17 16:17:10
            [date_modified] => 2014-09-03 18:20:57
            [order] => 1.00
            [children] => Array
                (
                )

        )

    [3] => stdClass Object
        (
            [id] => 3
            [company_id] => 1
            [name] => Boys and girls
            [slug] => boys-and-girls
            [parent_id] => 
            [depth] => 0
            [lft] => 17
            [rgt] => 20
            [is_enabled] => 1
            [image_url] => toys-for-girls-and-boys.jpg
            [date_created] => 2012-04-17 16:17:31
            [date_modified] => 2014-09-03 18:26:16
            [order] => 3.00
            [children] => Array
                (
                    [11] => stdClass Object
                        (
                            [id] => 11
                            [company_id] => 1
                            [name] => kenny
                            [slug] => kenny
                            [parent_id] => 3
                            [depth] => 1
                            [lft] => 18
                            [rgt] => 19
                            [is_enabled] => 1
                            [image_url] => 
                            [date_created] => 2012-08-24 13:30:37
                            [date_modified] => 2012-08-24 13:30:37
                            [order] => 3.50
                            [children] => Array
                                (
                                )

                        )

                )

        )

)