Re : how to catch 404s with can.route.pushstate

I'm thinking that there are 4 types of "unroutables":

1. external host/port
2. external path (outside app root)
3. ignored route (can.route.ignore)
4. unrouted path

1. /*
2.     @param {Event} event
3.     @param {Object} data Contains route information.
4.     @param {URLUtils} url
5. */
6. can.route.bind("unroutable", function(event, data, url)
7. {
8.     var loc = window.location;
9.     
10.     if (url.host != loc.host || url.port != loc.port || url.protocol != loc.protocol)
11.     {
12.         // different host/port
13.     }
14.     else if (url.pathname.indexOf(can.route.bindings.pushstate.root) != 0)
15.     {
16.         // external path (outside app root)
17.     }
18.     else if (data.route === false)
19.     {
20.         // ignored route
21.     }
22.     else if ( can.isEmptyObject(data.route) )
23.     {
24.         // unrouted (simulated 404?)
25.     }
26.     
27.     // stops links from refreshing the page (for whatever reason)
28.     if (event.currentTarget.tagName == "A")
29.     {
30.         event.preventDefault();
31.     }
32. });