get_pages: exclude by slug

I made a simple change to get_pages that I think will benefit a lot of people.

The get_pages() function allows you to exclude certain pages from the results, but it requires you to hard-code the page IDs you want to exclude. It’s far more useful to be able to exclude by slug. So I modified the function to do this.

The new syntax is: exclude=<id or slug>. If it’s a number, it’s an ID. If it’s not a number, it’s a slug. So, to get the children of page $papa avoiding any whose slug is “hidden”, do:

$pages = get_pages("parent=$papa&hierarchical=0&exclude=hidden")

and it works like a charm. (Since the id-or-slug convention is used elsewhere too I figured it’d be good here too.)

Here’s the code change:

wp-includes/post.php:

2071:	function &get_pages($args = '') {
...

2114:		$exclusions = '';
		if ( !empty($exclude) ) {
			$expages = preg_split('/[\s,]+/',$exclude);
			if ( count($expages) ) {
				foreach ( $expages as $expage ) {
++++					$exfield = is_numeric($expage) ? 'ID' : 'post_name';
					if (empty($exclusions))
----						$exclusions = $wpdb->prepare(' AND ( ID <> %d ', $expage);
++++						$exclusions = $wpdb->prepare(" AND ( $exfield <> %s ", $expage);
 					else
----						$exclusions .= $wpdb->prepare(' AND ID <> %d ', $expage);
++++						$exclusions .= $wpdb->prepare(" AND $exfield <> %s ", $expage);
 				}
 			}
 		}

(I was making a template for a new web site, and in it there’s a dynamically generated drop-down menu of pages and their subpages. But some of a page’s children are actually page fragments I embed in the parent page with a custom template, like an editable sidebar. I needed to be able to exclude those page fragments without hard-coding their IDs.)