    # File lib/rack/utils.rb, line 557
          def to_params_hash
            hash = @params
            hash.keys.each do |key|
              value = hash[key]
              if value.kind_of?(self.class)
                if value.object_id == self.object_id
                  hash[key] = hash
                else
                  hash[key] = value.to_params_hash
                end
              elsif value.kind_of?(Array)
                value.map! {|x| x.kind_of?(self.class) ? x.to_params_hash : x}
              end
            end
            hash
          end