# File lib/rack/utils.rb, line 101
101:     def build_query(params)
102:       params.map { |k, v|
103:         if v.class == Array
104:           build_query(v.map { |x| [k, x] })
105:         else
106:           "#{escape(k)}=#{escape(v)}"
107:         end
108:       }.join("&")
109:     end