export declare const MONTH_COUNT: number[][];
export declare const initGregorianFields: (f: number[]) => void;
/**
 * Compute fields for dates on or after the Gregorian cutover.
 */
export declare const computeGregorianFields: (f: number[]) => void;
/**
 * Compute fields for dates before the Gregorian cutover using the proleptic
 * Julian calendar. Any Gregorian date before October 15, 1582 is really a
 * date on the proleptic Julian calendar, with leap years every 4 years.
 */
export declare const computeJulianFields: (f: number[]) => void;
/**
 * Returns the number of days in the given month for the given year. The month must be 0-based.
 */
export declare const daysInMonth: (y: number, m: number) => number;
export declare const monthStart: (eyear: number, month: number, _useMonth: boolean) => number;
/**
 * Return true if the given year is a leap year in the Gregorian calendar; false otherwise.
 * Note that we switch to the Julian calendar at the Gregorian cutover year.
 */
export declare const leapGregorian: (y: number) => boolean;
/**
 * Convert integer (year, month, day) to Julian day.
 */
export declare const ymdToJD: (y: number, m: number, d: number, monthCount: number) => number;