}

func (m mapNil[a, b]) Apply(_ Nil[a]) any {
	return Nil[b]{}
}

type mapCons[a, b any] struct {
	f Function[a, b]
}

func (m mapCons[a, b]) Apply(xs Cons[a]) any {
	return Cons[b]{m.f.Apply(xs.Head), Map[a, b](m.f, xs.Tail)}
}

func Map[a, b any](f Function[a, b], xs List[a]) List[b] {
	return xs.Match(mapNil[a, b]{}, mapCons[a, b]{f}).(List[b])
}

func main() {

const wzURL = "https://raw.githubusercontent.com/unicode-org/cldr/main/common/supplemental/windowsZones.xml"

type MapZone struct {
	Other     string `xml:"other,attr"`
	Territory string `xml:"territory,attr"`
	Type      string `xml:"type,attr"`
}

type SupplementalData struct {
	Zones []MapZone `xml:"windowsZones>mapTimezones>mapZone"`
}

func readWindowsZones() ([]*zone, error) {
	r, err := http.Get(wzURL)
	if err != nil {