import type { ImmutableArray } from "./array.js";
import type { AnyCaller } from "./function.js";
/** ISO 4217 currency code, e.g. `GBP` or `USD`. */
export type CurrencyCode = string;
/** Array of all supported currency codes in this runtime. */
export declare const CURRENCY_CODES: ImmutableArray<CurrencyCode>;
/**
 * Require that a value is a valid ISO 4217 currency code, and return it as a `Currency` type.
 */
export declare function getCurrencyCode(value: string): CurrencyCode | undefined;
/**
 * Require that a value is a valid ISO 4217 currency code, and return it as a `Currency` type.
 */
export declare function requireCurrencyCode(value: string, caller?: AnyCaller): CurrencyCode;
/**
 * Get the display symbol used for a currency.
 *
 * @throws {RequiredError} If the currency code is malformed or unsupported.
 *
 * @example getCurrencySymbol("GBP"); // "£"
 */
export declare function getCurrencySymbol(currency: CurrencyCode, caller?: AnyCaller): string;
/**
 * Get the "step" value for a currency, i.e. the smallest fractional unit that is used for that currency.
 * - E.g. `0.01` for USD, `0.001` for some cryptocurrencies, and `1` for JPY.
 * @throws {RequiredError} If the currency code is malformed or unsupported.
 */
export declare function getCurrencyStep(currency: CurrencyCode, caller?: AnyCaller): number;