class AcceptLanguageHeaderTransform < HeaderTransform
      rule(language: simple(:e), q: simple(:q)) { LanguageRange.new(e, q) }
      rule(language: simple(:e)) { LanguageRange.new(e) }
      rule(accept_language: sequence(:lr)) { Headers::AcceptLanguage.new(*lr) }
      rule(accept_language: simple(:lr)) { Headers::AcceptLanguage.new(lr) }