[db-wg] Specifying no routes

All,

I want to do something like the following:

import:  from as<number> accept NONE except
              {
              from community.contains(val-a) action community.append(val-aa); accept any;
              from community.contains(val-b) action community.append(val-bb); accept any;
              }

That is to say, on my peering with as<number> I want to accept routes based on communities but add a new community based on the value of the existing one, and then accept the route. Is this a suitable syntax - except for the lack of a NONE keyword? Or can I fake this by using 0.0.0.0 instead of NONE? Or is there a better solution altogether?

Thanks for any tips,
--

Tim