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// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.// This module is browser compatible.
function isYearNumberALeapYear(yearNumber: number): boolean {  return (    (yearNumber % 4 === 0 && yearNumber % 100 !== 0) || yearNumber % 400 === 0  );}
/** * Returns whether the given year is a leap year. Passing in a * {@linkcode Date} object will return the leap year status of the year of that * object and take the current timezone into account. Passing in a number will * return the leap year status of that number. * * This is based on * {@link https://docs.microsoft.com/en-us/office/troubleshoot/excel/determine-a-leap-year}. * * @param year The year in number or `Date` format. * @returns `true` if the given year is a leap year; `false` otherwise. * * @example Basic usage * ```ts * import { isLeap } from "https://deno.land/std@$STD_VERSION/datetime/is_leap.ts"; * * isLeap(new Date("1970-01-02")); // false * * isLeap(1970); // false * * isLeap(new Date("1972-01-02")); // true * * isLeap(1972); // true * ``` * * @example Accounting for timezones * ```ts * import { isLeap } from "https://deno.land/std@$STD_VERSION/datetime/is_leap.ts"; * * isLeap(new Date("2000-01-01")); * // true if the local timezone is GMT+0; false if the local timezone is GMT-1 * * isLeap(2000); * // true regardless of the local timezone * ``` */export function isLeap(year: Date | number): boolean {  const yearNumber = year instanceof Date ? year.getFullYear() : year;  return isYearNumberALeapYear(yearNumber);}
/** * Returns whether the given year is a leap year in UTC time. This always * returns the same value regardless of the local timezone.
 * This is based on * {@link https://docs.microsoft.com/en-us/office/troubleshoot/excel/determine-a-leap-year}. * * @param year The year in number or `Date` format. * @returns `true` if the given year is a leap year; `false` otherwise. * * @example Basic usage * ```ts * import { isUtcLeap } from "https://deno.land/std@$STD_VERSION/datetime/is_leap.ts"; * * isUtcLeap(new Date("2000-01-01")); // true * * isUtcLeap(new Date("December 31, 1999 23:59:59 GMT-01:00")); // true * * isUtcLeap(2000); // true * * isUtcLeap(1999); // false * ``` */export function isUtcLeap(year: Date | number): boolean {  const yearNumber = year instanceof Date ? year.getUTCFullYear() : year;  return isYearNumberALeapYear(yearNumber);}