# File lib/sinatra/rabbit.rb, line 160
      def effective_params(driver)
        driver.features(@collection.name).collect do |f|
          f.decl.operation(@name)
        end.flatten.select { |op| op }.inject(params.dup) do |result, fop|
          fop.params.each_key do |k|
            if result.has_key?(k)
              raise DuplicateParamException, "Parameter '#{k}' for operation #{fop.name} in collection #{@collection.name}"
            else
              result[k] = fop.params[k]
            end
          end
          result
        end
      end