*/ interface Currencies extends IteratorAggregate { /** * Checks whether a currency is available in the current context. */ public function contains(Currency $currency): bool; /** * Returns the subunit for a currency. * * @throws UnknownCurrencyException If currency is not available in the current context. */ public function subunitFor(Currency $currency): int; /** * @return Traversable */ public function getIterator(): Traversable; }