In your views, layouts and handlers you can use the buildLink method provided by the request context object (event) to build routable links in your application.
Just pass in the routed URL or event and it will create the appropriate routed URL for you:
The request context object (event) also has some handy methods to tell you the name or even the current route that was selected for execution:
getCurrentRouteName() - Gives you the name of the current route, if any
getCurrentRoute() - Gives you the currently executed route
getCurrentRoutedURL() - Gives you the complete routed URL pattern that matched the route
getCurrentRoutedNamespace() - Gives you the current routed namespace, if any