Add is_interwiki_link method

modules/feature-interwiki-links.php

@@ -89,4 +89,14 @@ function interwiki_get_pagename_url($interwiki_pagename) {
 	);
 }
 
+/**
+ * Returns whether a given pagename is an interwiki link or not.
+ * Note that this doesn't guarantee that it's a _valid_ interwiki link - only that it looks like one :P
+ * @param	string	$pagename	The page name to check.
+ * @return	boolean	Whether the given page name is an interwiki link or not.
+ */
+function is_interwiki_link($pagename) {
+	return strpos($pagename, ":") !== false;
+}
+
 ?>