# File lib/grape/dsl/routing.rb, line 163
        def namespace(space = nil, options = {}, &block)
          if space || block_given?
            within_namespace do
              previous_namespace_description = @namespace_description
              @namespace_description = (@namespace_description || {}).deep_merge(namespace_setting(:description) || {})
              nest(block) do
                if space
                  namespace_stackable(:namespace, Namespace.new(space, options))
                end
              end
              @namespace_description = previous_namespace_description
            end
          else
            Namespace.joined_space_path(namespace_stackable(:namespace))
          end
        end