menu_item_menu_item_parent', true ) ) &&
					! in_array( $_anc_id, $active_ancestor_item_ids )
				) {
					$active_ancestor_item_ids[] = $_anc_id;
				}

				if ( in_array( home_url(), array( untrailingslashit( $current_url ), untrailingslashit( $_indexless_current ) ) ) ) {
					// Back compat for home link to match wp_page_menu()
					$classes[] = 'current_page_item';
				}
				$active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
				$active_parent_object_ids[] = (int) $menu_item->post_parent;
				$active_object = $menu_item->object;

			// give front page item current-menu-item class when extra query arguments involved
			} elseif ( $item_url == $front_page_url && is_front_page() ) {
				$classes[] = 'current-menu-item';
			}

			if ( untrailingslashit($item_url) == home_url() )
				$classes[] = 'menu-item-home';
		}

		// back-compat with wp_page_menu: add "current_page_parent" to static home page link for any non-page query
		if ( ! empty( $home_page_id ) && 'post_type' == $menu_item->type && empty( $wp_query->is_page ) && $home_page_id == $menu_item->object_id )
			$classes[] = 'current_page_parent';

		$menu_items[$key]->classes = array_unique( $classes );
	}
	$active_ancestor_item_ids = array_filter( array_unique( $active_ancestor_item_ids ) );
	$active_parent_item_ids = array_filter( array_unique( $active_parent_item_ids ) );
	$active_parent_object_ids = array_filter( array_unique( $active_parent_object_ids ) );

	// set parent's class
	foreach ( (array) $menu_items as $key => $parent_item ) {
		$classes = (array) $parent_item->classes;
		$menu_items[$key]->current_item_ancestor = false;
		$menu_items[$key]->current_item_parent = false;

		if (
			isset( $parent_item->type ) &&
			(
				// ancestral post object
				(
					'post_type' == $parent_item->type &&
					! empty( $queried_object->post_type ) &&
					is_post_type_hierarchical( $queried_object->post_type ) &&
					in_array( $parent_item->object_id, $queried_object->ancestors ) &&
					$parent_item->object != $queried_object->ID
				) ||

				// ancestral term
				(
					'taxonomy' == $parent_item->type &&
					isset( $possible_taxonomy_ancestors[ $parent_item->object ] ) &&
					in_array( $parent_item->object_id, $possible_taxonomy_ancestors[ $parent_item->object ] ) &&
					(
						! isset( $queried_object->term_id ) ||
						$parent_item->object_id != $queried_object->term_id
					)
				)
			)
		) {
			$classes[] = empty( $queried_object->taxonomy ) ? 'current-' . $queried_object->post_type . '-ancestor' : 'current-' . $queried_object->taxonomy . '-ancestor';
		}

		if ( in_array(  intval( $parent_item->db_id ), $active_ancestor_item_ids ) ) {
			$classes[] = 'current-menu-ancestor';
			$menu_items[$key]->current_item_ancestor = true;
		}
		if ( in_array( $parent_item->db_id, $active_parent_item_ids ) ) {
			$classes[] = 'current-menu-parent';
			$menu_items[$key]->current_item_parent = true;
		}
		if ( in_array( $parent_item->object_id, $active_parent_object_ids ) )
			$classes[] = 'current-' . $active_object . '-parent';

		if ( 'post_type' == $parent_item->type && 'page' == $parent_item->object ) {
			// Back compat classes for pages to match wp_page_menu()
			if ( in_array('current-menu-parent', $classes) )
				$classes[] = 'current_page_parent';
			if ( in_array('current-menu-ancestor', $classes) )
				$classes[] = 'current_page_ancestor';
		}

		$menu_items[$key]->classes = array_unique( $classes );
	}
}

/**
 * Retrieve the HTML list content for nav menu items.
 *
 * @uses Walker_Nav_Menu to create HTML list content.
 * @since 3.0.0
 *
 * @param array    $items The menu items, sorted by each menu item's menu order.
 * @param int      $depth Depth of the item in reference to parents.
 * @param stdClass $r     An object containing wp_nav_menu() arguments.
 * @return string The HTML list content for the menu items.
 */
function walk_nav_menu_tree( $items, $depth, $r ) {
	$walker = ( empty($r->walker) ) ? new Walker_Nav_Menu : $r->walker;
	$args = array( $items, $depth, $r );

	return call_user_func_array( array( $walker, 'walk' ), $args );
}

/**
 * Prevents a menu item ID from being used more than once.
 *
 * @since 3.0.1
 * @access private
 *
 * @staticvar array $used_ids
 * @param string $id
 * @param object $item
 * @return string
 */
function _nav_menu_item_id_use_once( $id, $item ) {
	static $_used_ids = array();
	if ( in_array( $item->ID, $_used_ids ) ) {
		return '';
	}
	$_used_ids[] = $item->ID;
	return $id;
}