Update routing.rst

routing.rst

@@ -77,7 +77,7 @@ to integrate the 404 page with the style of your overall website:
 
 Modifying the URL
 -----------------
-
+  For example:
 You can obtain *and modify* the URL of the current page using [WebBrowser.url](https://github.com/kwebio/kweb-core/blob/master/src/main/kotlin/kweb/WebBrowser.kt#L98).
 
 
@@ -103,7 +103,7 @@ Here is a more realistic example:
                     path("/number/{num}") { params ->
                         val num = params.getValue("num").toInt()
                         a().text(num.map {"Number $it"}).on.click {
-                            url.value++
+                            num.value++
                         }
                     }
                 }
@@ -115,4 +115,6 @@ If you visit http://localhost:16097/ the URL will immediately update to http://l
 without a page refresh, and you'll see a hyperlink with text "Number 1".  If you click on this link
 you'll see that the number increments (both in the URL and in the link text), also without a page refresh.
 
-
+The line *num.value++* is worthy of additional attention.  *num* is a KVar<Int>, and so it can be  
+incremented via its *value* property.  This will cause the page URL to update, which will in-turn cause
+the DOM to update to reflect the new URL.  All of this is handled for you by Kweb.