# File lib/getoptions.rb, line 186
  def [](k)
    raise ParseError.new("`nil' cannot be an option key") if (k.nil?)
    sym = k.to_sym
    key = k.to_s

    case
    when @options.has_key?(sym); @options[sym]
    when @dict.has_key?(key);    (@dict[key].option_type == :increment) ? 0 : nil
    else raise ParseError.new("program tried to access an unknown option: #{key.inspect}")
    end
  end