# File lib/rack/utils.rb, line 75
    def parse_nested_query(qs, d = nil)
      params = {}

      max_key_space = Utils.key_space_limit
      bytes = 0

      (qs || '').split(d ? /[#{d}] */n : DEFAULT_SEP).each do |p|
        k, v = unescape(p).split('=', 2)

        if k
          bytes += k.size
          if bytes > max_key_space
            raise RangeError, "exceeded available parameter key space"
          end
        end

        normalize_params(params, k, v)
      end