import { HDate } from '@hebcal/hdate';
/**
 * Returns `true` if the given date falls within a public period of communal
 * mourning — specifically:
 *
 * - **Sefirat HaOmer**: 16 Nisan through 5 Sivan (the 49 days of the Omer).
 * - **Bein HaMetzarim** ("between the straits"): 17 Tammuz through 9 Av
 *   (10 Av when 9 Av is postponed because it falls on Shabbat).
 *
 * This is a broad helper — it does not attempt to model minhag-specific
 * exceptions within those periods (e.g. Lag BaOmer, Rosh Chodesh Iyar,
 * the distinction between Sephardic and Ashkenazic customs on which
 * portion of the Omer is observed as mourning, etc.).
 * @example
 * import {isAveilut, HDate, months} from '@hebcal/core';
 * isAveilut(new HDate(20, months.NISAN, 5784)); // true (Omer)
 * isAveilut(new HDate(25, months.TAMUZ, 5784)); // true (Three Weeks)
 * isAveilut(new HDate(15, months.AV, 5784));    // false
 * @param date Hebrew Date, Gregorian date, or absolute R.D. day number
 * @return `true` if the date is during a mourning period
 */
export declare function isAveilut(date: HDate | Date | number): boolean;