| blob | 78ba115638ad69203b19f847f45180791b5dbcac |
1 ;;; holidays.el --- holiday functions for the calendar package
3 ;; Copyright (C) 1989, 1990, 1992, 1993, 1994, 1997, 2001, 2002, 2003,
4 ;; 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
5 ;; Free Software Foundation, Inc.
7 ;; Author: Edward M. Reingold <reingold@cs.uiuc.edu>
8 ;; Maintainer: Glenn Morris <rgm@gnu.org>
9 ;; Keywords: holidays, calendar
10 ;; Package: calendar
12 ;; This file is part of GNU Emacs.
14 ;; GNU Emacs is free software: you can redistribute it and/or modify
15 ;; it under the terms of the GNU General Public License as published by
16 ;; the Free Software Foundation, either version 3 of the License, or
17 ;; (at your option) any later version.
19 ;; GNU Emacs is distributed in the hope that it will be useful,
20 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
21 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 ;; GNU General Public License for more details.
24 ;; You should have received a copy of the GNU General Public License
25 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
27 ;;; Commentary:
29 ;; See calendar.el.
31 ;;; Code:
37 "Holidays support in calendar."
42 ;; The various holiday variables are autoloaded because people
43 ;; are used to using them to set calendar-holidays without having to
44 ;; explicitly load this file.
46 ;;;###autoload
49 ;;;###autoload
69 "General holidays. Default value is for the United States.
70 See the documentation for `calendar-holidays' for details."
73 ;;;###autoload
76 ;;;###autoload
79 ;;;###autoload
92 ))))
93 "Oriental holidays.
94 See the documentation for `calendar-holidays' for details."
98 ;;;###autoload
101 ;;;###autoload
103 ;;;###autoload
105 "Local holidays.
106 See the documentation for `calendar-holidays' for details."
109 ;;;###autoload
112 ;;;###autoload
114 ;;;###autoload
116 "User defined holidays.
117 See the documentation for `calendar-holidays' for details."
120 ;;;###autoload
123 ;;;###autoload
129 11
132 year)
138 22
141 ;;;###autoload
145 ;;;###autoload
151 10
163 ;;;###autoload
167 ;;;###autoload
172 11
194 day)
197 ;;;###autoload
201 ;;;###autoload
218 ;;;###autoload
222 ;;;###autoload
225 ;;;###autoload
235 "Jewish holidays.
236 See the documentation for `calendar-holidays' for details."
240 ;;;###autoload
243 ;;;###autoload
246 ;;;###autoload
258 "Christian holidays.
259 See the documentation for `calendar-holidays' for details."
262 ;;;###autoload
265 ;;;###autoload
268 ;;;###autoload
282 "Islamic holidays.
283 See the documentation for `calendar-holidays' for details."
286 ;;;###autoload
289 ;;;###autoload
291 ;;;###autoload
305 "Baha'i holidays.
306 See the documentation for `calendar-holidays' for details."
309 ;;;###autoload
312 ;;;###autoload
314 ;;;###autoload
322 calendar-standard-time-zone-name)))
327 calendar-daylight-time-zone-name)))))
328 "Sun-related holidays.
329 See the documentation for `calendar-holidays' for details."
332 ;;;###autoload
335 ;; This one should not be autoloaded, else .emacs changes of
336 ;; holiday-general-holidays etc have no effect.
337 ;; FIXME should have some :set-after.
340 holiday-other-holidays holiday-christian-holidays
341 holiday-hebrew-holidays holiday-islamic-holidays
342 holiday-bahai-holidays holiday-oriental-holidays
343 holiday-solar-holidays)
346 Additional holidays are easy to add to the list, just put them in the
347 list `holiday-other-holidays' in your .emacs file. Similarly, by setting
348 any of `holiday-general-holidays', `holiday-local-holidays',
349 `holiday-christian-holidays', `holiday-hebrew-holidays',
350 `holiday-islamic-holidays', `holiday-bahai-holidays',
351 `holiday-oriental-holidays', or `holiday-solar-holidays' to nil in your
352 .emacs file, you can eliminate unwanted categories of holidays.
354 The aforementioned variables control the holiday choices offered
355 by the function `holiday-list' when it is called interactively.
357 They also initialize the default value of `calendar-holidays',
358 which is the default list of holidays used by the function
359 `holiday-list' in the non-interactive case. Note that these
360 variables have no effect on `calendar-holidays' after it has been
361 set (e.g. after the calendar is loaded). In that case, customize
362 `calendar-holidays' directly.
364 The intention is that (in the US) `holiday-local-holidays' be set in
365 site-init.el and `holiday-other-holidays' be set by the user.
367 Entries on the list are expressions that return (possibly empty) lists of
368 items of the form ((month day year) string) of a holiday in the
369 three-month period centered around `displayed-month' of `displayed-year'.
370 Several basic functions are provided for this purpose:
372 (holiday-fixed MONTH DAY STRING) is a fixed date on the Gregorian calendar
373 (holiday-float MONTH DAYNAME K STRING &optional DAY) is the Kth DAYNAME
374 (0 for Sunday, etc.) after/before Gregorian
375 MONTH DAY. K<0 means count back from the end
376 of the month. Optional DAY defaults to 1 if
377 K>0, and MONTH's last day otherwise.
378 (holiday-hebrew MONTH DAY STRING) a fixed date on the Hebrew calendar
379 (holiday-islamic MONTH DAY STRING) a fixed date on the Islamic calendar
380 (holiday-bahai MONTH DAY STRING) a fixed date on the Baha'i calendar
381 (holiday-julian MONTH DAY STRING) a fixed date on the Julian calendar
382 (holiday-sexp SEXP STRING) SEXP is a Gregorian-date-valued expression
383 in the variable `year'; if it evaluates to
384 a visible date, that's the holiday; if it
385 evaluates to nil, there's no holiday. STRING
386 is an expression in the variable `date'.
388 For example, to add Bastille Day, celebrated in France on July 14, add
392 to the list. To add Hurricane Supplication Day, celebrated in the Virgin
393 Islands on the fourth Monday in August, add
397 to the list (the last Monday would be specified with `-1' instead of `4').
398 To add the last day of Hanukkah to the list, use
402 since the Hebrew months are numbered with 1 starting from Nisan.
403 To add the Islamic feast celebrating Mohammed's birthday, use
407 since the Islamic months are numbered from 1 starting with Muharram.
408 To add an entry for the Baha'i festival of Ridvan, use
412 since the Baha'i months are numbered from 1 starting with Baha.
413 To add Thomas Jefferson's birthday, April 2, 1743 (Julian), use
417 To include a holiday conditionally, use the sexp form or a conditional. For
418 example, to include American presidential elections, which occur on the first
419 Tuesday after the first Monday in November of years divisible by 4, add
421 (holiday-sexp
422 '(if (zerop (% year 4))
423 (calendar-gregorian-from-absolute
424 (1+ (calendar-dayname-on-or-before
425 1 (+ 6 (calendar-absolute-from-gregorian
426 (list 11 1 year)))))))
429 or
431 (if (zerop (% displayed-year 4))
432 (holiday-fixed 11
433 (calendar-extract-day
434 (calendar-gregorian-from-absolute
435 (1+ (calendar-dayname-on-or-before
436 1 (+ 6 (calendar-absolute-from-gregorian
437 (list 11 1 displayed-year)))))))
440 to the list. To include the phases of the moon, add
442 (lunar-phases)
444 to the holiday list, where `lunar-phases' is an Emacs-Lisp function that
445 you've written to return a (possibly empty) list of the relevant VISIBLE dates
446 with descriptive strings such as
451 ;;;###autoload
454 ;;; End of user options.
457 ;; FIXME name that makes sense
458 ;;;###diary-autoload
460 "Form the list of holidays that occur on dates in the calendar window.
461 The holidays are those in the list `calendar-holidays'."
479 ;; FIXME name that makes sense
480 ;;;###cal-autoload
482 "Create a buffer containing the holidays for the current calendar window.
483 The holidays are those in the list `calendar-notable-days'.
484 Returns non-nil if any holidays are found.
485 If EVENT is non-nil, it's an event indicating the buffer position to
486 use instead of point."
488 ;; If called from a menu, with the calendar window not selected.
515 holiday-list)))
520 ;;;###autoload
522 "Display the holidays for last month, this month, and next month.
523 If called with an optional prefix argument ARG, prompts for month and year.
524 This function is suitable for execution in a .emacs file."
534 ;; rms: "Emacs commands to display a list of something generally start
535 ;; with `list-'. Please make `list-holidays' the principal name."
536 ;;;###autoload
538 "Display holidays for years Y1 to Y2 (inclusive).
539 Y2 defaults to Y1. The optional list of holidays L defaults to
540 `calendar-holidays'. If you want to control what holidays are
541 displayed, use a different list. For example,
543 (list-holidays 2006 2006
544 (append holiday-general-holidays holiday-local-holidays))
546 will display holidays for the year 2006 defined in the two
547 mentioned lists, and nothing else.
549 When called interactively, this command offers a choice of
550 holidays, based on the variables `holiday-solar-holidays' etc. See the
551 documentation of `calendar-holidays' for a list of the variables
552 that control the choices, as well as a description of the format
553 of a holiday list.
555 The optional LABEL is used to label the buffer created."
558 "Starting year of holidays (>0): "
564 start-year)
598 choice
600 "Holidays"
611 holiday-list)
630 ;;;###autoload
633 ;;;###diary-autoload
635 "Check the list of holidays for any that occur on DATE.
636 The value returned is a list of strings of relevant holiday descriptions.
637 The holidays are those in the list `calendar-holidays'."
640 holiday-list)
650 ;;;###cal-autoload
652 "Find holidays for the date specified by the cursor in the calendar window.
653 Optional DATE is a list (month day year) to use instead of the
654 cursor position. EVENT specifies a buffer position to use for a date."
660 selection msg)
680 ;; FIXME move to calendar?
681 ;;;###cal-autoload
683 "Mark notable days in the calendar window.
684 If EVENT is non-nil, it's an event indicating the buffer position to
685 use instead of point."
687 ;; If called from a menu, with the calendar window not selected.
700 ;; Below are the functions that calculate the dates of holidays; these
701 ;; are eval'ed in the function calendar-holiday-list. If you
702 ;; write other such functions, be sure to imitate the style used below.
703 ;; Remember that each function must return a list of items of the form
704 ;; ((month day year) string) of VISIBLE dates in the calendar window.
707 "Holiday on MONTH, DAY (Gregorian) called STRING.
708 If MONTH, DAY is visible, the value returned is the list (((MONTH DAY year)
709 STRING)). Returns nil if it is not visible in the current calendar window."
710 ;; This determines whether a given month is visible in the calendar.
711 ;; cf calendar-date-is-visible-p (which also checks the year part).
712 ;; The day is irrelevant since only full months are displayed.
713 ;; Since the calendar displays three months at a time, month N
714 ;; is visible if displayed-month = N-1, N, N+1.
715 ;; In particular, November is visible if d-m = 10, 11, 12.
716 ;; This is useful, because we can do a one-sided test:
717 ;; November is visible if d-m > 9. (Similarly, February is visible if
718 ;; d-m < 4.)
719 ;; To determine if December is visible, we can shift the calendar
720 ;; back a month and ask if November is visible; to determine if
721 ;; October is visible, we can shift it forward a month and ask if
722 ;; November is visible; etc.
730 "Holiday called STRING on the Nth DAYNAME after/before MONTH DAY.
731 DAYNAME=0 means Sunday, DAYNAME=1 means Monday, and so on.
732 If N>0, use the Nth DAYNAME after MONTH DAY.
733 If N<0, use the Nth DAYNAME before MONTH DAY.
734 DAY defaults to 1 if N>0, and MONTH's last day otherwise.
735 If the holiday is visible in the calendar window, returns a
736 list (((month day year) STRING)). Otherwise returns nil."
737 ;; This is messy because the holiday may be visible, while the date
738 ;; on which it is based is not. For example, the first Monday after
739 ;; December 30 may be visible when January is not. For large values
740 ;; of |n| the problem is more grotesque. If we didn't have to worry
741 ;; about such cases, we could just use the original version of this
742 ;; function:
743 ;; (let ((m displayed-month)
744 ;; (y displayed-year))
745 ;; (calendar-increment-month m y (- 11 month))
746 ;; (if (> m 9); month in year y is visible
747 ;; (list (list (calendar-nth-named-day n dayname month y day) string)))))
767 y1
768 y2))
771 1
777 string)))))
780 "Filter list of holidays HLIST, and return only the visible ones.
781 HLIST is a list of elements of the form (DATE) TEXT."
784 hlist)))
790 "Sexp holiday for dates in the calendar window.
791 SEXP is an expression in variable `year' that is evaluated to
792 give `date'. STRING is an expression in `date' that evaluates to
793 the holiday description of `date'. If `date' is visible in the
794 calendar window, the holiday STRING is on that date. If date is
795 nil, or if the date is not visible, there is no holiday."
798 year date)
813 "Date of Nth day after advent (named STRING), if visible in calendar window.
814 Negative values of N are interpreted as days before advent.
815 STRING is used purely for display purposes. The return value has
816 the form ((MONTH DAY YEAR) STRING), where the date is that of the
817 Nth day before or after advent.
819 For backwards compatibility, if this function is called with no
820 arguments, then it returns the value appropriate for advent itself."
821 ;; Backwards compatibility layer.
829 (+ n
831 0
838 "Date of Nth day after Easter (named STRING), if visible in calendar window.
839 Negative values of N are interpreted as days before Easter.
840 STRING is used purely for display purposes. The return value has
841 the form ((MONTH DAY YEAR) STRING), where the date is that of the
842 Nth day before or after Easter.
844 For backwards compatibility, if this function is called with no
846 holidays (with more entries if `calendar-christian-all-holidays-flag'
847 is non-nil)."
848 ;; Backwards compatibility layer.
853 ;; The combined list is not in order.
886 shifted-epact))
889 adjusted-epact))
895 ;; Prior call to calendar-julian-from-absolute will autoload cal-julian.
899 "Date of Easter according to the rule of the Council of Nicaea."
914 shifted-epact))
923 ;;; holidays.el ends here