import { Calendar } from './calendar';
import { JulianDate } from "./julian-date";
import { GregorianDate } from "./gregorian-date";
export declare type JulianDays = {
    days: number;
    unknownYear: boolean;
    unknownMonth: boolean;
    unknownDay: boolean;
};
export declare function isLeapYear(year: number | undefined, calendar?: Calendar): boolean;
export declare function createDate(year: number | undefined, month: number | undefined, day: number | undefined, calendar?: Calendar): GregorianDate | JulianDate;
export declare function createDateFromString(text: string, calendar?: Calendar): GregorianDate | JulianDate;
export declare function parseDateString(text: string): {
    day: number;
    month: number;
    year: number;
} | null;