// attempt to infer their values.
// TODO: consider removing
func (t Tag) Raw() (b Language, s Script, r Region) {
	return t.LangID, t.ScriptID, t.RegionID
}

// equalTags compares language, script and region subtags only.
func (t Tag) equalTags(a Tag) bool {
	return t.LangID == a.LangID && t.ScriptID == a.ScriptID && t.RegionID == a.RegionID
}

// IsRoot returns true if t is equal to language "und".
func (t Tag) IsRoot() bool {