setWeek.d.mts 1.7 KB

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  1. import type {
  2. FirstWeekContainsDateOptions,
  3. LocalizedOptions,
  4. WeekOptions,
  5. } from "./types.js";
  6. /**
  7. * The {@link setWeek} function options.
  8. */
  9. export interface SetWeekOptions
  10. extends LocalizedOptions<"options">,
  11. WeekOptions,
  12. FirstWeekContainsDateOptions {}
  13. /**
  14. * @name setWeek
  15. * @category Week Helpers
  16. * @summary Set the local week to the given date.
  17. *
  18. * @description
  19. * Set the local week to the given date, saving the weekday number.
  20. * The exact calculation depends on the values of
  21. * `options.weekStartsOn` (which is the index of the first day of the week)
  22. * and `options.firstWeekContainsDate` (which is the day of January, which is always in
  23. * the first week of the week-numbering year)
  24. *
  25. * Week numbering: https://en.wikipedia.org/wiki/Week#The_ISO_week_date_system
  26. *
  27. * @typeParam DateType - The `Date` type, the function operates on. Gets inferred from passed arguments. Allows to use extensions like [`UTCDate`](https://github.com/date-fns/utc).
  28. *
  29. * @param date - The date to be changed
  30. * @param week - The week of the new date
  31. * @param options - An object with options
  32. *
  33. * @returns The new date with the local week set
  34. *
  35. * @example
  36. * // Set the 1st week to 2 January 2005 with default options:
  37. * const result = setWeek(new Date(2005, 0, 2), 1)
  38. * //=> Sun Dec 26 2004 00:00:00
  39. *
  40. * @example
  41. * // Set the 1st week to 2 January 2005,
  42. * // if Monday is the first day of the week,
  43. * // and the first week of the year always contains 4 January:
  44. * const result = setWeek(new Date(2005, 0, 2), 1, {
  45. * weekStartsOn: 1,
  46. * firstWeekContainsDate: 4
  47. * })
  48. * //=> Sun Jan 4 2004 00:00:00
  49. */
  50. export declare function setWeek<DateType extends Date>(
  51. date: DateType | number | string,
  52. week: number,
  53. options?: SetWeekOptions,
  54. ): DateType;