//#region src/calendar-system/gregorian.d.ts
/**
 * Pure helpers for proleptic Gregorian arithmetic.
 *
 * Shared by every non-Gregorian calendar system (Jalaali, Hijri, Hebrew) so the
 * `[31, 28/29, 31, 30, ...]` table and the leap-year rule live in exactly one place.
 */
/**
 * Returns `true` when `y` is a Gregorian leap year (divisible by 4 but not 100,
 * unless also divisible by 400).
 */
declare function isGregorianLeap(y: number): boolean;
/**
 * Returns the number of days in a Gregorian month.
 *
 * @param gy - Gregorian year
 * @param gm - 1-indexed Gregorian month (1 = January, 12 = December)
 * @returns Days in the month (28-31), or 31 as a defensive fallback for out-of-range `gm`.
 */
declare function gregorianMonthLength(gy: number, gm: number): number;
//#endregion
export { gregorianMonthLength, isGregorianLeap };