def route_for!(name)
      route = route_for(name)
      raise RouteNotFoundError.new(("Route not found for %s" % [name])) if route.nil?
      route
    end
def route_for!(name)
      route = route_for(name)
      raise RouteNotFoundError.new(("Route not found for %s" % [name])) if route.nil?
      route
    end
Raise an exception of the route's not found