# File lib/rhc/cartridge_helpers.rb, line 59
      def web_carts_only
        lambda{ |cart|
          next cart unless cart.is_a? Array
          name = cart.instance_variable_get(:@for)
          matching = cart.select{ |c| not c.only_in_existing? }
          if matching.size == 1
            use_cart(matching.first, name)
          else
            matching.instance_variable_set(:@for, name)
            matching
          end
        }
      end