app

# File actionpack/lib/action_dispatch/routing/mapper.rb, line 299
          def app(blocks)
            if to.respond_to?(:action)
              Routing::RouteSet::StaticDispatcher.new to
            elsif to.respond_to?(:call)
              Constraints.new(to, blocks, Constraints::CALL)
            elsif blocks.any?
              Constraints.new(dispatcher(defaults.key?(:controller)), blocks, Constraints::SERVE)
            else
              dispatcher(defaults.key?(:controller))
            end
          end