CurrencyAffixes
class CurrencyAffixes(val positivePrefix: String, val positiveSuffix: String, val negativePrefix: String, val negativeSuffix: String, val fractionDigits: Int)
Where a locale puts the currency sign, and how many fraction digits the currency has.
Affixes rather than a symbol and a placement flag: a locale can put a non-breaking space between the sign and the digits, move the sign for negatives, or use a different sign entirely for the negative form, and every platform this reads from exposes the four affixes directly.