def merge_modes modes
      addition = true

      modes.each_char do |char|
        case char
        when ?+
          addition = true
        when ?-
          addition = false
        else
          addition ? @modes.concat(char) : @modes.delete!(char)
        end
      end
    end
def merge_modes modes
      addition = true

      modes.each_char do |char|
        case char
        when ?+
          addition = true
        when ?-
          addition = false
        else
          addition ? @modes.concat(char) : @modes.delete!(char)
        end
      end
    end
Instantiate a user with a nickname, a network and a user list.
 Merge the channels mode corresponding to the leading character (+ or -).

 @param [String] modes the modes to merge with.