import { BigNumber as BigNumberJs } from 'bignumber.js';
import BaseExchangeApi, { CurrencyMapping } from './BaseExchangeApi';
export declare type RateRecord = Record<string, string>;
export declare abstract class StableCoinExchange extends BaseExchangeApi {
    protected sourceToken: string;
    protected rates: Record<string, RateRecord>;
    constructor(sourceToken: string, api: string, currencyMapping: CurrencyMapping);
    queryExchangeRate(sourceCurrency: string, targetCurrency: string): Promise<BigNumberJs>;
}