class DEBUGGER__::Config

def initialize argv
  if self.class.config
    raise 'Can not make multiple configurations in one process'
  end
  config = self.class.parse_argv(argv)
  # apply defaults
  CONFIG_SET.each do |k, config_detail|
    unless config.key?(k)
      default_value = config_detail[3]
      config[k] = parse_config_value(k, default_value)
    end
  end
  update config
end