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import toDate from '../toDate/index.ts'import requiredArgs from '../_lib/requiredArgs/index.ts'
/** * @name getDecade * @category Decade Helpers * @summary Get the decade of the given date. * * @description * Get the decade of the given date. * * ### v2.0.0 breaking changes: * * - [Changes that are common for the whole library](https://github.com/date-fns/date-fns/blob/master/docs/upgradeGuide.md#Common-Changes). * * @param {Date|Number} date - the given date * @returns {Number} the year of decade * @throws {TypeError} 1 argument required * * @example * // Which decade belongs 27 November 1942? * const result = getDecade(new Date(1942, 10, 27)) * //=> 1940 */export default function getDecade(dirtyDate: Date | number): number {  requiredArgs(1, arguments)
  const date = toDate(dirtyDate)  const year = date.getFullYear()  const decade = Math.floor(year / 10) * 10  return decade}