extracted the route wildcard translation to a separate method.

system/router.php

@@ -41,9 +41,7 @@ class Router {
 			{
 				foreach (explode(', ', $keys) as $key)
 				{
-					$key = str_replace(':num', '[0-9]+', str_replace(':any', '[a-zA-Z0-9\-_]+', $key));
-
-					if (preg_match('#^'.$key.'$#', $uri))
+					if (preg_match('#^'.$key = static::translate_wildcards($key).'$#', $uri))
 					{
 						return Request::$route = new Route($keys, $callback, static::parameters($uri, $key));
 					}
@@ -85,6 +83,17 @@ class Router {
 		return (file_exists($path = APP_PATH.'routes/'.$segments[0].EXT)) ? array_merge(require $path, $home) : $home;
 	}
 
+	/**
+	 * Translate route URI wildcards to regular expressions.
+	 *
+	 * @param  string  $key
+	 * @return string
+	 */
+	private static function translate_wildcards($key)
+	{
+		return str_replace(':num', '[0-9]+', str_replace(':any', '[a-zA-Z0-9\-_]+', $key));
+	}
+
 	/**
 	 * Extract the parameters from a URI based on a route URI.
 	 *