sealed_currencies 1.5.1

Provides data for world currencies in the form of sealed classes.

example/lib/main.dart

// ignore_for_file: avoid_print, prefer-match-file-name

import "package:sealed_currencies/sealed_currencies.dart";

void main() {
  print(FiatCurrency.list.length); // Prints: "169".

  final serbianDinar = FiatCurrency.fromCode("RSD");
  print(serbianDinar.name); // Prints: "Serbian Dinar".

  final maybeEuro = FiatCurrency.maybeFromValue(
    "Euro",
    where: (currency) => currency.namesNative.first,
  );
  print(maybeEuro?.isEur); // Prints: true.
  print(maybeEuro?.toString(short: false));
  /*
  Prints: "FiatCurrency(code: "EUR", name: "Euro", decimalMark: ",",
  thousandsSeparator: ".", symbol: r"€", htmlEntity: "€", codeNumeric: "978",
  namesNative: ["Euro"], priority: 2, smallestDenomination: 1, subunit: "Cent",
  subunitToUnit: 100, unitFirst: true), translations: eurCurrencyTranslations".
  */

  print(isVikingKrone(const FiatNok())); // Prints "true".
  print(isVikingKrone(serbianDinar)); // Prints "null".
  print(isVikingKrone(const FiatCzk())); // Prints "false".

  FiatCurrency.list
      .where((currency) => currency.symbol?.contains("kr") ?? false)
      .forEach(print);
  // Prints:
  // Currency(code: DKK)
  // Currency(code: ISK)
  // Currency(code: NOK)
  // Currency(code: SEK).

  serbianDinar.toJson(); // Converts currency to a valid JSON.

  // Prints German translations of all available regular currencies.
  for (final currency in FiatCurrency.list) {
    print(
      "German name of ${currency.name}: "
      "${currency.maybeTranslation(const BasicLocale(LangDeu()))?.name}",
    );
  }

  print(const _FiatCustom().name); // Prints "Custom".
}

/// [Currency] is a sealed class, it means
/// this `whenOrNull` can be used same way as switch:
/// ```dart
/// switch (currency) {
///  case FiatDkk():
///  case FiatIsk():
///  case FiatNok():
///  case FiatSek():
///    return true;
///  case FiatCzk():
///    return false;
///  default:
///    return null;
///}
/// ```
// ignore: prefer-static-class, just for example.
bool? isVikingKrone(FiatCurrency currency) => currency.whenOrNull(
      fiatCzk: () => false,
      fiatDkk: () => true,
      fiatIsk: () => true,
      fiatNok: () => true,
      fiatSek: () => true,
    );

/// Creates a instance of the custom currency with permissive constructor.
class _FiatCustom extends FiatCurrency {
  const _FiatCustom() : super.permissive(code: "123", name: "Custom");
}