class SassListen::Options

def initialize(opts, defaults)
  @options = {}
  given_options = opts.dup
  defaults.keys.each do |key|
    @options[key] = given_options.delete(key) || defaults[key]
  end
  return if given_options.empty?
  msg = "Unknown options: #{given_options.inspect}"
  SassListen::Logger.warn msg
  fail msg
end