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import toDate from '../toDate/index.ts'import requiredArgs from '../_lib/requiredArgs/index.ts'
/** * @name isLeapYear * @category Year Helpers * @summary Is the given date in the leap year? * * @description * Is the given date in the leap year? * * ### 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 date to check * @returns {Boolean} the date is in the leap year * @throws {TypeError} 1 argument required * * @example * // Is 1 September 2012 in the leap year? * var result = isLeapYear(new Date(2012, 8, 1)) * //=> true */export default function isLeapYear(dirtyDate: Date | number): boolean {  requiredArgs(1, arguments)
  const date = toDate(dirtyDate)  const year = date.getFullYear()  return year % 400 === 0 || (year % 4 === 0 && year % 100 !== 0)}