differenceInCalendarISOWeekYears.js 1.3 KB

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  1. import { normalizeDates } from "./_lib/normalizeDates.js";
  2. import { getISOWeekYear } from "./getISOWeekYear.js";
  3. /**
  4. * The {@link differenceInCalendarISOWeekYears} function options.
  5. */
  6. /**
  7. * @name differenceInCalendarISOWeekYears
  8. * @category ISO Week-Numbering Year Helpers
  9. * @summary Get the number of calendar ISO week-numbering years between the given dates.
  10. *
  11. * @description
  12. * Get the number of calendar ISO week-numbering years between the given dates.
  13. *
  14. * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
  15. *
  16. * @param laterDate - The later date
  17. * @param earlierDate - The earlier date
  18. * @param options - An object with options
  19. *
  20. * @returns The number of calendar ISO week-numbering years
  21. *
  22. * @example
  23. * // How many calendar ISO week-numbering years are 1 January 2010 and 1 January 2012?
  24. * const result = differenceInCalendarISOWeekYears(
  25. * new Date(2012, 0, 1),
  26. * new Date(2010, 0, 1)
  27. * )
  28. * //=> 2
  29. */
  30. export function differenceInCalendarISOWeekYears(
  31. laterDate,
  32. earlierDate,
  33. options,
  34. ) {
  35. const [laterDate_, earlierDate_] = normalizeDates(
  36. options?.in,
  37. laterDate,
  38. earlierDate,
  39. );
  40. return (
  41. getISOWeekYear(laterDate_, options) - getISOWeekYear(earlierDate_, options)
  42. );
  43. }
  44. // Fallback for modularized imports:
  45. export default differenceInCalendarISOWeekYears;