lisp/calendar/calendar.el

   1 ;;; calendar.el --- calendar functions
   2
   3 ;; Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1997,
   4 ;;      2000, 2001, 2003 Free Software Foundation, Inc.
   5
   6 ;; Author: Edward M. Reingold <reingold@cs.uiuc.edu>
   7 ;; Keywords: calendar
   8 ;; Human-Keywords: calendar, Gregorian calendar, diary, holidays
   9
  10 ;; This file is part of GNU Emacs.
  11
  12 ;; GNU Emacs is free software; you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation; either version 2, or (at your option)
  15 ;; any later version.
  16
  17 ;; GNU Emacs is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  24 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  25 ;; Boston, MA 02111-1307, USA.
  26
  27 ;;; Commentary:
  28
  29 ;; This collection of functions implements a calendar window.  It generates a
  30 ;; calendar for the current month, together with the previous and coming
  31 ;; months, or for any other three-month period.  The calendar can be scrolled
  32 ;; forward and backward in the window to show months in the past or future;
  33 ;; the cursor can move forward and backward by days, weeks, or months, making
  34 ;; it possible, for instance, to jump to the date a specified number of days,
  35 ;; weeks, or months from the date under the cursor.  The user can display a
  36 ;; list of holidays and other notable days for the period shown; the notable
  37 ;; days can be marked on the calendar, if desired.  The user can also specify
  38 ;; that dates having corresponding diary entries (in a file that the user
  39 ;; specifies) be marked; the diary entries for any date can be viewed in a
  40 ;; separate window.  The diary and the notable days can be viewed
  41 ;; independently of the calendar.  Dates can be translated from the (usual)
  42 ;; Gregorian calendar to the day of the year/days remaining in year, to the
  43 ;; ISO commercial calendar, to the Julian (old style) calendar, to the Hebrew
  44 ;; calendar, to the Islamic calendar, to the French Revolutionary calendar, to
  45 ;; the Mayan calendar, to the Chinese calendar, to the Coptic calendar, to the
  46 ;; Ethiopic calendar, and to the astronomical (Julian) day number.  When
  47 ;; floating point is available, times of sunrise/sunset can be displayed, as
  48 ;; can the phases of the moon.  Appointment notification for diary entries is
  49 ;; available.  Calendar printing via LaTeX is available.
  50
  51 ;; The following files are part of the calendar/diary code:
  52
  53 ;;       appt.el                       Appointment notification
  54 ;;       cal-china.el                  Chinese calendar
  55 ;;       cal-coptic.el                 Coptic/Ethiopic calendars
  56 ;;       cal-dst.el                    Daylight savings time rules
  57 ;;       cal-hebrew.el                 Hebrew calendar
  58 ;;       cal-islam.el                  Islamic calendar
  59 ;;       cal-iso.el                    ISO calendar
  60 ;;       cal-julian.el                 Julian/astronomical calendars
  61 ;;       cal-mayan.el                  Mayan calendars
  62 ;;       cal-menu.el                   Menu support
  63 ;;       cal-move.el                   Movement in the calendar
  64 ;;       cal-persia.el                 Persian calendar
  65 ;;       cal-tex.el                    Calendars in LaTeX
  66 ;;       cal-x.el                      X-windows dedicated frame functions
  67 ;;       diary-lib.el                  Diary functions
  68 ;;       holidays.el                   Holiday functions
  69 ;;       lunar.el                      Phases of the moon
  70 ;;       solar.el                      Sunrise/sunset, equinoxes/solstices
  71
  72 ;; Technical details of all the calendrical calculations can be found in
  73 ;; ``Calendrical Calculations'' by Nachum Dershowitz and Edward M. Reingold,
  74 ;; Cambridge University Press (1997).
  75
  76 ;; An earlier version of the technical details appeared in
  77 ;; ``Calendrical Calculations'' by Nachum Dershowitz and Edward M. Reingold,
  78 ;; Software--Practice and Experience, Volume 20, Number 9 (September, 1990),
  79 ;; pages 899-928.  ``Calendrical Calculations, Part II: Three Historical
  80 ;; Calendars'' by E. M. Reingold,  N. Dershowitz, and S. M. Clamen,
  81 ;; Software--Practice and Experience, Volume 23, Number 4 (April, 1993),
  82 ;; pages 383-404.
  83
  84 ;; Hard copies of these two papers can be obtained by sending email to
  85 ;; reingold@cs.uiuc.edu with the SUBJECT "send-paper-cal" (no quotes) and
  86 ;; the message BODY containing your mailing address (snail).
  87
  88 ;; Comments, corrections, and improvements should be sent to
  89 ;;  Edward M. Reingold               Department of Computer Science
  90 ;;  (217) 333-6733                   University of Illinois at Urbana-Champaign
  91 ;;  reingold@cs.uiuc.edu             1304 West Springfield Avenue
  92 ;;                                   Urbana, Illinois 61801
  93
  94 ;;; Code:
  95
  96 (eval-when-compile
  97   (defvar displayed-month)
  98   (defvar displayed-year)
  99   (defvar calendar-month-name-array)
 100   (defvar calendar-starred-day))
 101
 102 (defun calendar-version ()
 103   (interactive)
 104   (message "Version 6, October 12, 1995"))
 105
 106 (defgroup calendar nil
 107   "Calendar and time management support."
 108   :group 'applications)
 109
 110 (defgroup diary nil
 111   "Emacs diary."
 112   :group 'calendar)
 113
 114 (defgroup appt nil
 115   "Appointment notification."
 116   :group 'calendar)
 117
 118 (defgroup holidays nil
 119   "Holidays support in calendar."
 120   :group 'calendar
 121   :prefix "calendar-"
 122   :group 'local)
 123
 124 (defgroup chinese-calendar nil
 125   "Chinese calendar support."
 126   :group 'calendar)
 127
 128 (defgroup calendar-tex nil
 129   "Options for printing calendar with LaTeX."
 130   :prefix "cal-tex-"
 131   :group 'calendar)
 132
 133 (defgroup calendar-hooks nil
 134   "Calendar hooks."
 135   :prefix "calendar-"
 136   :group 'calendar)
 137
 138
 139 ;;;###autoload
 140 (defcustom calendar-week-start-day 0
 141   "*The day of the week on which a week in the calendar begins.
 142 0 means Sunday (default), 1 means Monday, and so on."
 143   :type 'integer
 144   :group 'calendar)
 145
 146 ;;;###autoload
 147 (defcustom calendar-offset 0
 148   "*The offset of the principal month from the center of the calendar window.
 149 0 means the principal month is in the center (default), -1 means on the left,
 150 +1 means on the right.  Larger (or smaller) values push the principal month off
 151 the screen."
 152   :type 'integer
 153   :group 'calendar)
 154
 155 ;;;###autoload
 156 (defcustom view-diary-entries-initially nil
 157   "*Non-nil means display current date's diary entries on entry.
 158 The diary is displayed in another window when the calendar is first displayed,
 159 if the current date is visible.  The number of days of diary entries displayed
 160 is governed by the variable `number-of-diary-entries'."
 161   :type 'boolean
 162   :group 'diary)
 163
 164 ;;;###autoload
 165 (defcustom number-of-diary-entries 1
 166   "*Specifies how many days of diary entries are to be displayed initially.
 167 This variable affects the diary display when the command \\[diary] is used,
 168 or if the value of the variable `view-diary-entries-initially' is t.  For
 169 example, if the default value 1 is used, then only the current day's diary
 170 entries will be displayed.  If the value 2 is used, then both the current
 171 day's and the next day's entries will be displayed.
 172
 173 The value can also be a vector such as [0 2 2 2 2 4 1]; this value
 174 says to display no diary entries on Sunday, the display the entries
 175 for the current date and the day after on Monday through Thursday,
 176 display Friday through Monday's entries on Friday, and display only
 177 Saturday's entries on Saturday.
 178
 179 This variable does not affect the diary display with the `d' command
 180 from the calendar; in that case, the prefix argument controls the
 181 number of days of diary entries displayed."
 182   :type '(choice (integer :tag "Entries")
 183                  (vector :value [0 0 0 0 0 0 0]
 184                          (integer :tag "Sunday")
 185                          (integer :tag "Monday")
 186                          (integer :tag "Tuesday")
 187                          (integer :tag "Wednesday")
 188                          (integer :tag "Thursday")
 189                          (integer :tag "Friday")
 190                          (integer :tag "Saturday")))
 191   :group 'diary)
 192
 193 ;;;###autoload
 194 (defcustom mark-diary-entries-in-calendar nil
 195   "*Non-nil means mark dates with diary entries, in the calendar window.
 196 The marking symbol is specified by the variable `diary-entry-marker'."
 197   :type 'boolean
 198   :group 'diary)
 199
 200 ;;;###autoload
 201 (defcustom calendar-remove-frame-by-deleting nil
 202   "*Determine how the calendar mode removes a frame no longer needed.
 203 If nil, make an icon of the frame.  If non-nil, delete the frame."
 204   :type 'boolean
 205   :group 'view)
 206
 207 (defvar diary-face 'diary-face
 208   "Face name to use for diary entries.")
 209 (defface diary-face
 210   '((((class color) (background light))
 211      :foreground "red")
 212     (((class color) (background dark))
 213      :foreground "yellow")
 214     (t
 215      :weight bold))
 216   "Face for highlighting diary entries."
 217   :group 'diary)
 218
 219 (defface calendar-today-face
 220   '((t (:underline t)))
 221   "Face for indicating today's date."
 222   :group 'diary)
 223
 224 (defface holiday-face
 225   '((((class color) (background light))
 226      :background "pink")
 227     (((class color) (background dark))
 228      :background "chocolate4")
 229     (t
 230      :inverse-video t))
 231   "Face for indicating dates that have holidays."
 232   :group 'diary)
 233
 234 (eval-after-load "facemenu"
 235   '(progn
 236      (add-to-list 'facemenu-unlisted-faces 'diary-face)
 237      (add-to-list 'facemenu-unlisted-faces 'calendar-today-face)
 238      (add-to-list 'facemenu-unlisted-faces 'holiday-face)))
 239
 240 (defcustom diary-entry-marker
 241   (if (not (display-color-p))
 242       "+"
 243     'diary-face)
 244   "*How to mark dates that have diary entries.
 245 The value can be either a single-character string or a face."
 246   :type '(choice string face)
 247   :group 'diary)
 248
 249 (defcustom calendar-today-marker
 250   (if (not (display-color-p))
 251       "="
 252     'calendar-today-face)
 253   "*How to mark today's date in the calendar.
 254 The value can be either a single-character string or a face.
 255 Marking today's date is done only if you set up `today-visible-calendar-hook'
 256 to request that."
 257   :type '(choice string face)
 258   :group 'calendar)
 259
 260 (defcustom calendar-holiday-marker
 261   (if (not (display-color-p))
 262       "*"
 263     'holiday-face)
 264   "*How to mark notable dates in the calendar.
 265 The value can be either a single-character string or a face."
 266   :type '(choice string face)
 267   :group 'calendar)
 268
 269 ;;;###autoload
 270 (defcustom view-calendar-holidays-initially nil
 271   "*Non-nil means display holidays for current three month period on entry.
 272 The holidays are displayed in another window when the calendar is first
 273 displayed."
 274   :type 'boolean
 275   :group 'holidays)
 276
 277 ;;;###autoload
 278 (defcustom mark-holidays-in-calendar nil
 279   "*Non-nil means mark dates of holidays in the calendar window.
 280 The marking symbol is specified by the variable `calendar-holiday-marker'."
 281   :type 'boolean
 282   :group 'holidays)
 283
 284 ;;;###autoload
 285 (defcustom all-hebrew-calendar-holidays nil
 286   "*If nil, show only major holidays from the Hebrew calendar.
 287 This means only those Jewish holidays that appear on secular calendars.
 288
 289 If t, show all the holidays that would appear in a complete Hebrew calendar."
 290   :type 'boolean
 291   :group 'holidays)
 292
 293 ;;;###autoload
 294 (defcustom all-christian-calendar-holidays nil
 295   "*If nil, show only major holidays from the Christian calendar.
 296 This means only those Christian holidays that appear on secular calendars.
 297
 298 If t, show all the holidays that would appear in a complete Christian
 299 calendar."
 300   :type 'boolean
 301   :group 'holidays)
 302
 303 ;;;###autoload
 304 (defcustom all-islamic-calendar-holidays nil
 305   "*If nil, show only major holidays from the Islamic calendar.
 306 This means only those Islamic holidays that appear on secular calendars.
 307
 308 If t, show all the holidays that would appear in a complete Islamic
 309 calendar."
 310   :type 'boolean
 311   :group 'holidays)
 312
 313 (defcustom diary-file-name-prefix-function (function (lambda (str) str))
 314   "*The function that will take a diary file name and return the desired prefix."
 315   :type 'function
 316   :group 'diary)
 317
 318 ;;;###autoload
 319 (defcustom calendar-load-hook nil
 320   "*List of functions to be called after the calendar is first loaded.
 321 This is the place to add key bindings to `calendar-mode-map'."
 322   :type 'hook
 323   :group 'calendar-hooks)
 324
 325 ;;;###autoload
 326 (defcustom initial-calendar-window-hook nil
 327   "*List of functions to be called when the calendar window is first opened.
 328 The functions invoked are called after the calendar window is opened, but
 329 once opened is never called again.  Leaving the calendar with the `q' command
 330 and reentering it will cause these functions to be called again."
 331   :type 'hook
 332   :group 'calendar-hooks)
 333
 334 ;;;###autoload
 335 (defcustom today-visible-calendar-hook nil
 336   "*List of functions called whenever the current date is visible.
 337 This can be used, for example, to replace today's date with asterisks; a
 338 function `calendar-star-date' is included for this purpose:
 339     (setq today-visible-calendar-hook 'calendar-star-date)
 340 It can also be used to mark the current date with `calendar-today-marker';
 341 a function is also provided for this:
 342     (setq today-visible-calendar-hook 'calendar-mark-today)
 343
 344 The corresponding variable `today-invisible-calendar-hook' is the list of
 345 functions called when the calendar function was called when the current
 346 date is not visible in the window.
 347
 348 Other than the use of the provided functions, the changing of any
 349 characters in the calendar buffer by the hooks may cause the failure of the
 350 functions that move by days and weeks."
 351   :type 'hook
 352   :group 'calendar-hooks)
 353
 354 ;;;###autoload
 355 (defcustom today-invisible-calendar-hook nil
 356   "*List of functions called whenever the current date is not visible.
 357
 358 The corresponding variable `today-visible-calendar-hook' is the list of
 359 functions called when the calendar function was called when the current
 360 date is visible in the window.
 361
 362 Other than the use of the provided functions, the changing of any
 363 characters in the calendar buffer by the hooks may cause the failure of the
 364 functions that move by days and weeks."
 365   :type 'hook
 366   :group 'calendar-hooks)
 367
 368 ;;;###autoload
 369 (defcustom calendar-move-hook nil
 370   "*List of functions called whenever the cursor moves in the calendar.
 371
 372 For example,
 373
 374   (add-hook 'calendar-move-hook (lambda () (view-diary-entries 1)))
 375
 376 redisplays the diary for whatever date the cursor is moved to."
 377   :type 'hook
 378   :group 'calendar-hooks)
 379
 380 ;;;###autoload
 381 (defcustom diary-file "~/diary"
 382   "*Name of the file in which one's personal diary of dates is kept.
 383
 384 The file's entries are lines beginning with any of the forms
 385 specified by the variable `american-date-diary-pattern', by default:
 386
 387             MONTH/DAY
 388             MONTH/DAY/YEAR
 389             MONTHNAME DAY
 390             MONTHNAME DAY, YEAR
 391             DAYNAME
 392
 393 with the remainder of the line being the diary entry string for
 394 that date.  MONTH and DAY are one or two digit numbers, YEAR is a
 395 number and may be written in full or abbreviated to the final two
 396 digits (if `abbreviated-calendar-year' is non-nil).  MONTHNAME
 397 and DAYNAME can be spelled in full (as specified by the variables
 398 `calendar-month-name-array' and `calendar-day-name-array'),
 399 abbreviated (as specified by `calendar-month-abbrev-array' and
 400 `calendar-day-abbrev-array') with or without a period,
 401 capitalized or not.  Any of DAY, MONTH, or MONTHNAME, YEAR can be
 402 `*' which matches any day, month, or year, respectively. If the
 403 date does not contain a year, it is generic and applies to any
 404 year.  A DAYNAME entry applies to the appropriate day of the week
 405 in every week.
 406
 407 The European style (in which the day precedes the month) can be
 408 used instead, if you execute `european-calendar' when in the
 409 calendar, or set `european-calendar-style' to t in your .emacs
 410 file.  The European forms (see `european-date-diary-pattern') are
 411
 412             DAY/MONTH
 413             DAY/MONTH/YEAR
 414             DAY MONTHNAME
 415             DAY MONTHNAME YEAR
 416             DAYNAME
 417
 418 To revert to the default American style from the European style, execute
 419 `american-calendar' in the calendar.
 420
 421 A diary entry can be preceded by the character
 422 `diary-nonmarking-symbol' (ordinarily `&') to make that entry
 423 nonmarking--that is, it will not be marked on dates in the calendar
 424 window but will appear in a diary window.
 425
 426 Multiline diary entries are made by indenting lines after the first with
 427 either a TAB or one or more spaces.
 428
 429 Lines not in one the above formats are ignored.  Here are some sample diary
 430 entries (in the default American style):
 431
 432      12/22/1988 Twentieth wedding anniversary!!
 433      &1/1. Happy New Year!
 434      10/22 Ruth's birthday.
 435      21: Payday
 436      Tuesday--weekly meeting with grad students at 10am
 437               Supowit, Shen, Bitner, and Kapoor to attend.
 438      1/13/89 Friday the thirteenth!!
 439      &thu 4pm squash game with Lloyd.
 440      mar 16 Dad's birthday
 441      April 15, 1989 Income tax due.
 442      &* 15 time cards due.
 443
 444 If the first line of a diary entry consists only of the date or day name with
 445 no trailing blanks or punctuation, then that line is not displayed in the
 446 diary window; only the continuation lines is shown.  For example, the
 447 single diary entry
 448
 449      02/11/1989
 450       Bill Blattner visits Princeton today
 451       2pm Cognitive Studies Committee meeting
 452       2:30-5:30 Lizzie at Lawrenceville for `Group Initiative'
 453       4:00pm Jamie Tappenden
 454       7:30pm Dinner at George and Ed's for Alan Ryan
 455       7:30-10:00pm dance at Stewart Country Day School
 456
 457 will appear in the diary window without the date line at the beginning.  This
 458 facility allows the diary window to look neater, but can cause confusion if
 459 used with more than one day's entries displayed.
 460
 461 Diary entries can be based on Lisp sexps.  For example, the diary entry
 462
 463       %%(diary-block 11 1 1990 11 10 1990) Vacation
 464
 465 causes the diary entry \"Vacation\" to appear from November 1 through November
 466 10, 1990.  Other functions available are `diary-float', `diary-anniversary',
 467 `diary-cyclic', `diary-day-of-year', `diary-iso-date', `diary-french-date',
 468 `diary-hebrew-date', `diary-islamic-date', `diary-mayan-date',
 469 `diary-chinese-date', `diary-coptic-date', `diary-ethiopic-date',
 470 `diary-persian-date', `diary-yahrzeit', `diary-sunrise-sunset',
 471 `diary-phases-of-moon', `diary-parasha', `diary-omer', `diary-rosh-hodesh',
 472 and `diary-sabbath-candles'.  See the documentation for the function
 473 `list-sexp-diary-entries' for more details.
 474
 475 Diary entries based on the Hebrew and/or the Islamic calendar are also
 476 possible, but because these are somewhat slow, they are ignored
 477 unless you set the `nongregorian-diary-listing-hook' and the
 478 `nongregorian-diary-marking-hook' appropriately.  See the documentation
 479 for these functions for details.
 480
 481 Diary files can contain directives to include the contents of other files; for
 482 details, see the documentation for the variable `list-diary-entries-hook'."
 483   :type 'file
 484   :group 'diary)
 485
 486 ;;;###autoload
 487 (defcustom diary-nonmarking-symbol "&"
 488   "*Symbol indicating that a diary entry is not to be marked in the calendar."
 489   :type 'string
 490   :group 'diary)
 491
 492 ;;;###autoload
 493 (defcustom hebrew-diary-entry-symbol "H"
 494   "*Symbol indicating a diary entry according to the Hebrew calendar."
 495   :type 'string
 496   :group 'diary)
 497
 498 ;;;###autoload
 499 (defcustom islamic-diary-entry-symbol "I"
 500   "*Symbol indicating a diary entry according to the Islamic calendar."
 501   :type 'string
 502   :group 'diary)
 503
 504 ;;;###autoload
 505 (defcustom diary-include-string "#include"
 506   "*The string indicating inclusion of another file of diary entries.
 507 See the documentation for the function `include-other-diary-files'."
 508   :type 'string
 509   :group 'diary)
 510
 511 (defcustom diary-glob-file-regexp-prefix "^\\#"
 512   "*The regular expression that gets pre-pended to each of the attribute-regexp's for file-wide specifiers."
 513   :type 'regexp
 514   :group 'diary)
 515
 516 (defcustom diary-face-attrs
 517   '((" *\\[foreground:\\([-a-z]+\\)\\]$" 1 :foreground string)
 518     (" *\\[background:\\([-a-z]+\\)\\]$" 1 :background string)
 519     (" *\\[width:\\([-a-z]+\\)\\]$" 1 :width symbol)
 520     (" *\\[height:\\([-0-9a-z]+\\)\\]$" 1 :height int)
 521     (" *\\[weight:\\([-a-z]+\\)\\]$" 1 :weight symbol)
 522     (" *\\[slant:\\([-a-z]+\\)\\]$" 1 :slant symbol)
 523     (" *\\[underline:\\([-a-z]+\\)\\]$" 1 :underline stringtnil)
 524     (" *\\[overline:\\([-a-z]+\\)\\]$" 1 :overline stringtnil)
 525     (" *\\[strike-through:\\([-a-z]+\\)\\]$" 1 :strike-through stringtnil)
 526     (" *\\[inverse-video:\\([-a-z]+\\)\\]$" 1 :inverse-video tnil)
 527     (" *\\[face:\\([-0-9a-z]+\\)\\]$" 1 :face string)
 528     (" *\\[font:\\([-a-z0-9]+\\)\\]$" 1 :font string)
 529     ;; Unsupported.
 530 ;;;    (" *\\[box:\\([-a-z]+\\)\\]$" 1 :box)
 531 ;;;    (" *\\[stipple:\\([-a-z]+\\)\\]$" 1 :stipple)
 532     )
 533   "*A list of (regexp regnum attr attrtype) lists where the
 534 regexp says how to find the tag, the regnum says which
 535 parenthetical sub-regexp this regexp looks for, and the attr says
 536 which attribute of the face (or that this _is_ a face) is being
 537 modified."
 538   :type 'sexp
 539   :group 'diary)
 540
 541 (defcustom diary-file-name-prefix nil
 542   "If non-nil each diary entry is prefixed with the name of the file where it is defined."
 543   :type 'boolean
 544   :group 'diary)
 545
 546 ;;;###autoload
 547 (defcustom sexp-diary-entry-symbol "%%"
 548   "*The string used to indicate a sexp diary entry in `diary-file'.
 549 See the documentation for the function `list-sexp-diary-entries'."
 550   :type 'string
 551   :group 'diary)
 552
 553 ;;;###autoload
 554 (defcustom abbreviated-calendar-year t
 555   "*Interpret a two-digit year DD in a diary entry as either 19DD or 20DD.
 556 For the Gregorian calendar; similarly for the Hebrew and Islamic calendars.
 557 If this variable is nil, years must be written in full."
 558   :type 'boolean
 559   :group 'diary)
 560
 561 ;;;###autoload
 562 (defcustom european-calendar-style nil
 563   "*Use the European style of dates in the diary and in any displays.
 564 If this variable is t, a date 1/2/1990 would be interpreted as February 1,
 565 1990.  The default European date styles (see `european-date-diary-pattern')
 566 are
 567
 568             DAY/MONTH
 569             DAY/MONTH/YEAR
 570             DAY MONTHNAME
 571             DAY MONTHNAME YEAR
 572             DAYNAME
 573
 574 Names can be capitalized or not, written in full (as specified by the
 575 variable `calendar-day-name-array'), or abbreviated (as specified by
 576 `calendar-day-abbrev-array') with or without a period."
 577   :type 'boolean
 578   :group 'diary)
 579
 580 ;;;###autoload
 581 (defcustom american-date-diary-pattern
 582   '((month "/" day "[^/0-9]")
 583     (month "/" day "/" year "[^0-9]")
 584     (monthname " *" day "[^,0-9]")
 585     (monthname " *" day ", *" year "[^0-9]")
 586     (dayname "\\W"))
 587   "*List of pseudo-patterns describing the American patterns of date used.
 588 See the documentation of `diary-date-forms' for an explanation."
 589   :type '(repeat (choice (cons :tag "Backup"
 590                                :value (backup . nil)
 591                                (const backup)
 592                                (repeat (list :inline t :format "%v"
 593                                              (symbol :tag "Keyword")
 594                                              (choice symbol regexp))))
 595                          (repeat (list :inline t :format "%v"
 596                                        (symbol :tag "Keyword")
 597                                        (choice symbol regexp)))))
 598   :group 'diary)
 599
 600 ;;;###autoload
 601 (defcustom european-date-diary-pattern
 602   '((day "/" month "[^/0-9]")
 603     (day "/" month "/" year "[^0-9]")
 604     (backup day " *" monthname "\\W+\\<\\([^*0-9]\\|\\([0-9]+[:aApP]\\)\\)")
 605     (day " *" monthname " *" year "[^0-9]")
 606     (dayname "\\W"))
 607   "*List of pseudo-patterns describing the European patterns of date used.
 608 See the documentation of `diary-date-forms' for an explanation."
 609   :type '(repeat (choice (cons :tag "Backup"
 610                                :value (backup . nil)
 611                                (const backup)
 612                                (repeat (list :inline t :format "%v"
 613                                              (symbol :tag "Keyword")
 614                                              (choice symbol regexp))))
 615                          (repeat (list :inline t :format "%v"
 616                                        (symbol :tag "Keyword")
 617                                        (choice symbol regexp)))))
 618   :group 'diary)
 619
 620 (defcustom diary-date-forms
 621   (if european-calendar-style
 622       european-date-diary-pattern
 623     american-date-diary-pattern)
 624   "*List of pseudo-patterns describing the forms of date used in the diary.
 625 The patterns on the list must be MUTUALLY EXCLUSIVE and should not match
 626 any portion of the diary entry itself, just the date component.
 627
 628 A pseudo-pattern is a list of regular expressions and the keywords `month',
 629 `day', `year', `monthname', and `dayname'.  The keyword `monthname' will
 630 match the name of the month (see `calendar-month-name-array'), capitalized
 631 or not, or its user-specified abbreviation (see `calendar-month-abbrev-array'),
 632 followed by a period or not; it will also match `*'.  Similarly, `dayname'
 633 will match the name of the day (see `calendar-day-name-array'), capitalized or
 634 not, or its user-specified abbreviation (see `calendar-day-abbrev-array'),
 635 followed by a period or not.  The keywords `month', `day', and `year' will
 636 match those numerical values, preceded by arbitrarily many zeros; they will
 637 also match `*'.
 638
 639 The matching of the diary entries with the date forms is done with the
 640 standard syntax table from Fundamental mode, but with the `*' changed so
 641 that it is a word constituent.
 642
 643 If, to be mutually exclusive, a pseudo-pattern must match a portion of the
 644 diary entry itself, the first element of the pattern MUST be `backup'.  This
 645 directive causes the date recognizer to back up to the beginning of the
 646 current word of the diary entry, so in no case can the pattern match more than
 647 a portion of the first word of the diary entry."
 648   :type '(repeat (choice (cons :tag "Backup"
 649                                :value (backup . nil)
 650                                (const backup)
 651                                (repeat (list :inline t :format "%v"
 652                                              (symbol :tag "Keyword")
 653                                              (choice symbol regexp))))
 654                          (repeat (list :inline t :format "%v"
 655                                        (symbol :tag "Keyword")
 656                                        (choice symbol regexp)))))
 657   :group 'diary)
 658
 659 ;;;###autoload
 660 (defcustom european-calendar-display-form
 661   '((if dayname (concat dayname ", ")) day " " monthname " " year)
 662   "*Pseudo-pattern governing the way a date appears in the European style.
 663 See the documentation of `calendar-date-display-form' for an explanation."
 664   :type 'sexp
 665   :group 'calendar)
 666
 667 ;;;###autoload
 668 (defcustom american-calendar-display-form
 669   '((if dayname (concat dayname ", ")) monthname " " day ", " year)
 670   "*Pseudo-pattern governing the way a date appears in the American style.
 671 See the documentation of `calendar-date-display-form' for an explanation."
 672   :type 'sexp
 673   :group 'calendar)
 674
 675 (defcustom calendar-date-display-form
 676   (if european-calendar-style
 677       european-calendar-display-form
 678     american-calendar-display-form)
 679   "*Pseudo-pattern governing the way a date appears.
 680
 681 Used by the function `calendar-date-string', a pseudo-pattern is a list of
 682 expressions that can involve the keywords `month', `day', and `year', all
 683 numbers in string form, and `monthname' and `dayname', both alphabetic
 684 strings.  For example, the ISO standard would use the pseudo- pattern
 685
 686        '(year \"-\" month \"-\" day)
 687
 688 while a typical American form would be
 689
 690        '(month \"/\" day \"/\" (substring year -2))
 691
 692 and
 693
 694        '((format \"%9s, %9s %2s, %4s\" dayname monthname day year))
 695
 696 would give the usual American style in fixed-length fields.
 697
 698 See the documentation of the function `calendar-date-string'."
 699   :type 'sexp
 700   :group 'calendar)
 701
 702 (defun european-calendar ()
 703   "Set the interpretation and display of dates to the European style."
 704   (interactive)
 705   (setq european-calendar-style t)
 706   (setq calendar-date-display-form european-calendar-display-form)
 707   (setq diary-date-forms european-date-diary-pattern)
 708   (update-calendar-mode-line))
 709
 710 (defun american-calendar ()
 711   "Set the interpretation and display of dates to the American style."
 712   (interactive)
 713   (setq european-calendar-style nil)
 714   (setq calendar-date-display-form american-calendar-display-form)
 715   (setq diary-date-forms american-date-diary-pattern)
 716   (update-calendar-mode-line))
 717
 718 ;;;###autoload
 719 (defcustom print-diary-entries-hook 'lpr-buffer
 720   "*List of functions called after a temporary diary buffer is prepared.
 721 The buffer shows only the diary entries currently visible in the diary
 722 buffer.  The default just does the printing.  Other uses might include, for
 723 example, rearranging the lines into order by day and time, saving the buffer
 724 instead of deleting it, or changing the function used to do the printing."
 725   :type 'hook
 726   :group 'diary)
 727
 728 ;;;###autoload
 729 (defcustom list-diary-entries-hook nil
 730   "*List of functions called after diary file is culled for relevant entries.
 731 It is to be used for diary entries that are not found in the diary file.
 732
 733 A function `include-other-diary-files' is provided for use as the value of
 734 this hook.  This function enables you to use shared diary files together
 735 with your own.  The files included are specified in the diary file by lines
 736 of the form
 737
 738         #include \"filename\"
 739
 740 This is recursive; that is, #include directives in files thus included are
 741 obeyed.  You can change the \"#include\" to some other string by changing
 742 the variable `diary-include-string'.  When you use `include-other-diary-files'
 743 as part of the list-diary-entries-hook, you will probably also want to use the
 744 function `mark-included-diary-files' as part of `mark-diary-entries-hook'.
 745
 746 For example, you could use
 747
 748      (setq list-diary-entries-hook
 749        '(include-other-diary-files sort-diary-entries))
 750      (setq diary-display-hook 'fancy-diary-display)
 751
 752 in your `.emacs' file to cause the fancy diary buffer to be displayed with
 753 diary entries from various included files, each day's entries sorted into
 754 lexicographic order."
 755   :type 'hook
 756   :group 'diary)
 757
 758 ;;;###autoload
 759 (defcustom diary-hook nil
 760   "*List of functions called after the display of the diary.
 761 Can be used for appointment notification."
 762   :type 'hook
 763   :group 'diary)
 764
 765 ;;;###autoload
 766 (defcustom diary-display-hook nil
 767   "*List of functions that handle the display of the diary.
 768 If nil (the default), `simple-diary-display' is used.  Use `ignore' for no
 769 diary display.
 770
 771 Ordinarily, this just displays the diary buffer (with holidays indicated in
 772 the mode line), if there are any relevant entries.  At the time these
 773 functions are called, the variable `diary-entries-list' is a list, in order
 774 by date, of all relevant diary entries in the form of ((MONTH DAY YEAR)
 775 STRING), where string is the diary entry for the given date.  This can be
 776 used, for example, a different buffer for display (perhaps combined with
 777 holidays), or produce hard copy output.
 778
 779 A function `fancy-diary-display' is provided as an alternative
 780 choice for this hook; this function prepares a special noneditable diary
 781 buffer with the relevant diary entries that has neat day-by-day arrangement
 782 with headings.  The fancy diary buffer will show the holidays unless the
 783 variable `holidays-in-diary-buffer' is set to nil.  Ordinarily, the fancy
 784 diary buffer will not show days for which there are no diary entries, even
 785 if that day is a holiday; if you want such days to be shown in the fancy
 786 diary buffer, set the variable `diary-list-include-blanks' to t."
 787   :type 'hook
 788   :group 'diary)
 789
 790 ;;;###autoload
 791 (defcustom nongregorian-diary-listing-hook nil
 792   "*List of functions called for listing diary file and included files.
 793 As the files are processed for diary entries, these functions are used to cull
 794 relevant entries.  You can use either or both of `list-hebrew-diary-entries'
 795 and `list-islamic-diary-entries'.  The documentation for these functions
 796 describes the style of such diary entries."
 797   :type 'hook
 798   :group 'diary)
 799
 800 ;;;###autoload
 801 (defcustom mark-diary-entries-hook nil
 802   "*List of functions called after marking diary entries in the calendar.
 803
 804 A function `mark-included-diary-files' is also provided for use as the
 805 `mark-diary-entries-hook'; it enables you to use shared diary files together
 806 with your own.  The files included are specified in the diary file by lines
 807 of the form
 808         #include \"filename\"
 809 This is recursive; that is, #include directives in files thus included are
 810 obeyed.  You can change the \"#include\" to some other string by changing the
 811 variable `diary-include-string'.  When you use `mark-included-diary-files' as
 812 part of the mark-diary-entries-hook, you will probably also want to use the
 813 function `include-other-diary-files' as part of `list-diary-entries-hook'."
 814   :type 'hook
 815   :group 'diary)
 816
 817 ;;;###autoload
 818 (defcustom nongregorian-diary-marking-hook nil
 819   "*List of functions called for marking diary file and included files.
 820 As the files are processed for diary entries, these functions are used to cull
 821 relevant entries.  You can use either or both of `mark-hebrew-diary-entries'
 822 and `mark-islamic-diary-entries'.  The documentation for these functions
 823 describes the style of such diary entries."
 824   :type 'hook
 825   :group 'diary)
 826
 827 ;;;###autoload
 828 (defcustom diary-list-include-blanks nil
 829   "*If nil, do not include days with no diary entry in the list of diary entries.
 830 Such days will then not be shown in the fancy diary buffer, even if they
 831 are holidays."
 832   :type 'boolean
 833   :group 'diary)
 834
 835 ;;;###autoload
 836 (defcustom holidays-in-diary-buffer t
 837   "*Non-nil means include holidays in the diary display.
 838 The holidays appear in the mode line of the diary buffer, or in the
 839 fancy diary buffer next to the date.  This slows down the diary functions
 840 somewhat; setting it to nil makes the diary display faster."
 841   :type 'boolean
 842   :group 'holidays)
 843
 844 (defvar calendar-mark-ring nil)
 845
 846 ;;;###autoload
 847 (put 'general-holidays 'risky-local-variable t)
 848 ;;;###autoload
 849 (defcustom general-holidays
 850   '((holiday-fixed 1 1 "New Year's Day")
 851     (holiday-float 1 1 3 "Martin Luther King Day")
 852     (holiday-fixed 2 2 "Groundhog Day")
 853     (holiday-fixed 2 14 "Valentine's Day")
 854     (holiday-float 2 1 3 "President's Day")
 855     (holiday-fixed 3 17 "St. Patrick's Day")
 856     (holiday-fixed 4 1 "April Fools' Day")
 857     (holiday-float 5 0 2 "Mother's Day")
 858     (holiday-float 5 1 -1 "Memorial Day")
 859     (holiday-fixed 6 14 "Flag Day")
 860     (holiday-float 6 0 3 "Father's Day")
 861     (holiday-fixed 7 4 "Independence Day")
 862     (holiday-float 9 1 1 "Labor Day")
 863     (holiday-float 10 1 2 "Columbus Day")
 864     (holiday-fixed 10 31 "Halloween")
 865     (holiday-fixed 11 11 "Veteran's Day")
 866     (holiday-float 11 4 4 "Thanksgiving"))
 867   "*General holidays.  Default value is for the United States.
 868 See the documentation for `calendar-holidays' for details."
 869   :type 'sexp
 870   :group 'holidays)
 871
 872 ;;;###autoload
 873 (put 'oriental-holidays 'risky-local-variable t)
 874 ;;;###autoload
 875 (defcustom oriental-holidays
 876   '((if (fboundp 'atan)
 877         (holiday-chinese-new-year)))
 878   "*Oriental holidays.
 879 See the documentation for `calendar-holidays' for details."
 880   :type 'sexp
 881   :group 'holidays)
 882
 883 ;;;###autoload
 884 (put 'local-holidays 'risky-local-variable t)
 885 ;;;###autoload
 886 (defcustom local-holidays nil
 887   "*Local holidays.
 888 See the documentation for `calendar-holidays' for details."
 889   :type 'sexp
 890   :group 'holidays)
 891
 892 ;;;###autoload
 893 (put 'other-holidays 'risky-local-variable t)
 894 ;;;###autoload
 895 (defcustom other-holidays nil
 896   "*User defined holidays.
 897 See the documentation for `calendar-holidays' for details."
 898   :type 'sexp
 899   :group 'holidays)
 900
 901 ;;;###autoload
 902 (put 'hebrew-holidays-1 'risky-local-variable t)
 903 ;;;###autoload
 904 (defvar hebrew-holidays-1
 905   '((holiday-rosh-hashanah-etc)
 906     (if all-hebrew-calendar-holidays
 907         (holiday-julian
 908          11
 909          (let* ((m displayed-month)
 910                 (y displayed-year)
 911                 (year))
 912            (increment-calendar-month m y -1)
 913            (let ((year (extract-calendar-year
 914                         (calendar-julian-from-absolute
 915                          (calendar-absolute-from-gregorian
 916                           (list m 1 y))))))
 917              (if (zerop (% (1+ year) 4))
 918                  22
 919                21))) "\"Tal Umatar\" (evening)"))))
 920
 921 ;;;###autoload
 922 (put 'hebrew-holidays-2 'risky-local-variable t)
 923 ;;;###autoload
 924 (defvar hebrew-holidays-2
 925   '((if all-hebrew-calendar-holidays
 926         (holiday-hanukkah)
 927       (holiday-hebrew 9 25 "Hanukkah"))
 928     (if all-hebrew-calendar-holidays
 929       (holiday-hebrew
 930        10
 931        (let ((h-year (extract-calendar-year
 932                       (calendar-hebrew-from-absolute
 933                        (calendar-absolute-from-gregorian
 934                         (list displayed-month 28 displayed-year))))))
 935          (if (= (% (calendar-absolute-from-hebrew (list 10 10 h-year))
 936                    7)
 937                 6)
 938              11 10))
 939        "Tzom Teveth"))
 940     (if all-hebrew-calendar-holidays
 941         (holiday-hebrew 11 15 "Tu B'Shevat"))))
 942
 943 ;;;###autoload
 944 (put 'hebrew-holidays-3 'risky-local-variable t)
 945 ;;;###autoload
 946 (defvar hebrew-holidays-3
 947   '((if all-hebrew-calendar-holidays
 948         (holiday-hebrew
 949          11
 950          (let ((m displayed-month)
 951                (y displayed-year))
 952            (increment-calendar-month m y 1)
 953            (let* ((h-year (extract-calendar-year
 954                            (calendar-hebrew-from-absolute
 955                             (calendar-absolute-from-gregorian
 956                              (list m
 957                                    (calendar-last-day-of-month m y)
 958                                    y)))))
 959                   (s-s
 960                    (calendar-hebrew-from-absolute
 961                     (if (=
 962                          (% (calendar-absolute-from-hebrew
 963                              (list 7 1 h-year))
 964                             7)
 965                          6)
 966                         (calendar-dayname-on-or-before
 967                          6 (calendar-absolute-from-hebrew
 968                             (list 11 17 h-year)))
 969                       (calendar-dayname-on-or-before
 970                        6 (calendar-absolute-from-hebrew
 971                           (list 11 16 h-year))))))
 972                   (day (extract-calendar-day s-s)))
 973              day))
 974          "Shabbat Shirah"))))
 975
 976 ;;;###autoload
 977 (put 'hebrew-holidays-4 'risky-local-variable t)
 978 ;;;###autoload
 979 (defvar hebrew-holidays-4
 980   '((holiday-passover-etc)
 981     (if (and all-hebrew-calendar-holidays
 982              (let* ((m displayed-month)
 983                     (y displayed-year)
 984                     (year))
 985                (increment-calendar-month m y -1)
 986                (let ((year (extract-calendar-year
 987                             (calendar-julian-from-absolute
 988                              (calendar-absolute-from-gregorian
 989                               (list m 1 y))))))
 990                  (= 21 (% year 28)))))
 991         (holiday-julian 3 26 "Kiddush HaHamah"))
 992     (if all-hebrew-calendar-holidays
 993         (holiday-tisha-b-av-etc))))
 994
 995 ;;;###autoload
 996 (put 'hebrew-holidays 'risky-local-variable t)
 997 ;;;###autoload
 998 (defcustom hebrew-holidays (append hebrew-holidays-1 hebrew-holidays-2
 999                                 hebrew-holidays-3 hebrew-holidays-4)
1000   "*Jewish holidays.
1001 See the documentation for `calendar-holidays' for details."
1002   :type 'sexp
1003   :group 'holidays)
1004
1005 ;;;###autoload
1006 (put 'christian-holidays 'risky-local-variable t)
1007 ;;;###autoload
1008 (defcustom christian-holidays
1009   '((if all-christian-calendar-holidays
1010         (holiday-fixed 1 6 "Epiphany"))
1011     (holiday-easter-etc)
1012     (if all-christian-calendar-holidays
1013         (holiday-greek-orthodox-easter))
1014     (if all-christian-calendar-holidays
1015         (holiday-fixed 8 15 "Assumption"))
1016     (if all-christian-calendar-holidays
1017         (holiday-advent))
1018     (holiday-fixed 12 25 "Christmas")
1019     (if all-christian-calendar-holidays
1020         (holiday-julian 12 25 "Eastern Orthodox Christmas")))
1021   "*Christian holidays.
1022 See the documentation for `calendar-holidays' for details."
1023   :type 'sexp
1024   :group 'holidays)
1025
1026 ;;;###autoload
1027 (put 'islamic-holidays 'risky-local-variable t)
1028 ;;;###autoload
1029 (defcustom islamic-holidays
1030   '((holiday-islamic
1031      1 1
1032      (format "Islamic New Year %d"
1033              (let ((m displayed-month)
1034                    (y displayed-year))
1035                (increment-calendar-month m y 1)
1036                (extract-calendar-year
1037                 (calendar-islamic-from-absolute
1038                  (calendar-absolute-from-gregorian
1039                   (list
1040                    m (calendar-last-day-of-month m y) y)))))))
1041     (if all-islamic-calendar-holidays
1042         (holiday-islamic 1 10 "Ashura"))
1043     (if all-islamic-calendar-holidays
1044         (holiday-islamic 3 12 "Mulad-al-Nabi"))
1045     (if all-islamic-calendar-holidays
1046         (holiday-islamic 7 26 "Shab-e-Mi'raj"))
1047     (if all-islamic-calendar-holidays
1048         (holiday-islamic 8 15 "Shab-e-Bara't"))
1049     (holiday-islamic 9 1 "Ramadan Begins")
1050     (if all-islamic-calendar-holidays
1051         (holiday-islamic 9 27 "Shab-e Qadr"))
1052     (if all-islamic-calendar-holidays
1053         (holiday-islamic 10 1 "Id-al-Fitr"))
1054     (if all-islamic-calendar-holidays
1055         (holiday-islamic 12 10 "Id-al-Adha")))
1056   "*Islamic holidays.
1057 See the documentation for `calendar-holidays' for details."
1058   :type 'sexp
1059   :group 'holidays)
1060
1061 ;;;###autoload
1062 (put 'solar-holidays 'risky-local-variable t)
1063 ;;;###autoload
1064 (defcustom solar-holidays
1065   '((if (fboundp 'atan)
1066         (solar-equinoxes-solstices))
1067     (if (progn
1068           (require 'cal-dst)
1069           t)
1070       (funcall
1071        'holiday-sexp
1072         calendar-daylight-savings-starts
1073         '(format "Daylight Savings Time Begins %s"
1074                   (if (fboundp 'atan)
1075                       (solar-time-string
1076                        (/ calendar-daylight-savings-starts-time (float 60))
1077                        calendar-standard-time-zone-name)
1078                     ""))))
1079     (funcall
1080      'holiday-sexp
1081      calendar-daylight-savings-ends
1082      '(format "Daylight Savings Time Ends %s"
1083               (if (fboundp 'atan)
1084                   (solar-time-string
1085                    (/ calendar-daylight-savings-ends-time (float 60))
1086                    calendar-daylight-time-zone-name)
1087                 ""))))
1088   "*Sun-related holidays.
1089 See the documentation for `calendar-holidays' for details."
1090   :type 'sexp
1091   :group 'holidays)
1092
1093 ;;;###autoload
1094 (put 'calendar-holidays 'risky-local-variable t)
1095 (defcustom calendar-holidays
1096   (append general-holidays local-holidays other-holidays
1097           christian-holidays hebrew-holidays islamic-holidays
1098           oriental-holidays solar-holidays)
1099   "*List of notable days for the command \\[holidays].
1100
1101 Additional holidays are easy to add to the list, just put them in the list
1102 `other-holidays' in your .emacs file.  Similarly, by setting any of
1103 `general-holidays', `local-holidays' `christian-holidays', `hebrew-holidays',
1104 `islamic-holidays', `oriental-holidays', or `solar-holidays' to nil in your
1105 .emacs file, you can eliminate unwanted categories of holidays.  The intention
1106 is that (in the US) `local-holidays' be set in site-init.el and
1107 `other-holidays' be set by the user.
1108
1109 Entries on the list are expressions that return (possibly empty) lists of
1110 items of the form ((month day year) string) of a holiday in the in the
1111 three-month period centered around `displayed-month' of `displayed-year'.
1112 Several basic functions are provided for this purpose:
1113
1114     (holiday-fixed MONTH DAY STRING) is a fixed date on the Gregorian calendar
1115     (holiday-float MONTH DAYNAME K STRING &optional day) is the Kth DAYNAME in
1116                                MONTH on the Gregorian calendar (0 for Sunday,
1117                                etc.); K<0 means count back from the end of the
1118                                month.  An optional parameter DAY means the Kth
1119                                DAYNAME after/before MONTH DAY.
1120     (holiday-hebrew MONTH DAY STRING)  a fixed date on the Hebrew calendar
1121     (holiday-islamic MONTH DAY STRING) a fixed date on the Islamic calendar
1122     (holiday-julian MONTH DAY STRING)  a fixed date on the Julian calendar
1123     (holiday-sexp SEXP STRING) SEXP is a Gregorian-date-valued expression
1124                                in the variable `year'; if it evaluates to
1125                                a visible date, that's the holiday; if it
1126                                evaluates to nil, there's no holiday.  STRING
1127                                is an expression in the variable `date'.
1128
1129 For example, to add Bastille Day, celebrated in France on July 14, add
1130
1131      (holiday-fixed 7 14 \"Bastille Day\")
1132
1133 to the list.  To add Hurricane Supplication Day, celebrated in the Virgin
1134 Islands on the fourth Monday in August, add
1135
1136      (holiday-float 8 1 4 \"Hurricane Supplication Day\")
1137
1138 to the list (the last Monday would be specified with `-1' instead of `4').
1139 To add the last day of Hanukkah to the list, use
1140
1141      (holiday-hebrew 10 2 \"Last day of Hanukkah\")
1142
1143 since the Hebrew months are numbered with 1 starting from Nisan, while to
1144 add the Islamic feast celebrating Mohammed's birthday use
1145
1146      (holiday-islamic 3 12 \"Mohammed's Birthday\")
1147
1148 since the Islamic months are numbered from 1 starting with Muharram.  To
1149 add Thomas Jefferson's birthday, April 2, 1743 (Julian), use
1150
1151      (holiday-julian 4 2 \"Jefferson's Birthday\")
1152
1153 To include a holiday conditionally, use the sexp form or a conditional.  For
1154 example, to include American presidential elections, which occur on the first
1155 Tuesday after the first Monday in November of years divisible by 4, add
1156
1157      (holiday-sexp
1158        (if (zerop (% year 4))
1159            (calendar-gregorian-from-absolute
1160              (1+ (calendar-dayname-on-or-before
1161                    1 (+ 6 (calendar-absolute-from-gregorian
1162                             (list 11 1 year)))))))
1163        \"US Presidential Election\")
1164
1165 or
1166
1167      (if (zerop (% displayed-year 4))
1168          (holiday-fixed 11
1169                 (extract-calendar-day
1170                  (calendar-gregorian-from-absolute
1171                   (1+ (calendar-dayname-on-or-before
1172                        1 (+ 6 (calendar-absolute-from-gregorian
1173                                (list 11 1 displayed-year)))))))
1174                 \"US Presidential Election\"))
1175
1176 to the list.  To include the phases of the moon, add
1177
1178      (lunar-phases)
1179
1180 to the holiday list, where `lunar-phases' is an Emacs-Lisp function that
1181 you've written to return a (possibly empty) list of the relevant VISIBLE dates
1182 with descriptive strings such as
1183
1184      (((2 6 1989) \"New Moon\") ((2 12 1989) \"First Quarter Moon\") ... )."
1185   :type 'sexp
1186   :group 'holidays)
1187
1188 (defconst calendar-buffer "*Calendar*"
1189   "Name of the buffer used for the calendar.")
1190
1191 (defconst holiday-buffer "*Holidays*"
1192   "Name of the buffer used for the displaying the holidays.")
1193
1194 (defconst fancy-diary-buffer "*Fancy Diary Entries*"
1195   "Name of the buffer used for the optional fancy display of the diary.")
1196
1197 (defconst other-calendars-buffer "*Other Calendars*"
1198   "Name of the buffer used for the display of date on other calendars.")
1199
1200 (defconst lunar-phases-buffer "*Phases of Moon*"
1201   "Name of the buffer used for the lunar phases.")
1202
1203 (defmacro increment-calendar-month (mon yr n)
1204   "Move the variables MON and YR to the month and year by N months.
1205 Forward if N is positive or backward if N is negative."
1206   `(let ((macro-y (+ (* ,yr 12) ,mon -1 ,n)))
1207     (setq ,mon (1+ (% macro-y 12)))
1208     (setq ,yr (/ macro-y 12))))
1209
1210 (defmacro calendar-for-loop (var from init to final do &rest body)
1211   "Execute a for loop."
1212   `(let ((,var (1- ,init)))
1213     (while (>= ,final (setq ,var (1+ ,var)))
1214       ,@body)))
1215
1216 (defmacro calendar-sum (index initial condition expression)
1217   "For INDEX = INITIAL et seq, as long as CONDITION holds, sum EXPRESSION."
1218   `(let ((,index ,initial)
1219          (sum 0))
1220     (while ,condition
1221       (setq sum (+ sum ,expression))
1222       (setq ,index (1+ ,index)))
1223     sum))
1224
1225 ;; The following are in-line for speed; they can be called thousands of times
1226 ;; when looking up holidays or processing the diary.  Here, for example, are
1227 ;; the numbers of calls to calendar/diary/holiday functions in preparing the
1228 ;; fancy diary display, for a moderately complex diary file, with functions
1229 ;; used instead of macros.  There were a total of 10000 such calls:
1230 ;;
1231 ;;  1934   extract-calendar-month
1232 ;;  1852   extract-calendar-year
1233 ;;  1819   extract-calendar-day
1234 ;;   845   calendar-leap-year-p
1235 ;;   837   calendar-day-number
1236 ;;   775   calendar-absolute-from-gregorian
1237 ;;   346   calendar-last-day-of-month
1238 ;;   286   hebrew-calendar-last-day-of-month
1239 ;;   188   hebrew-calendar-leap-year-p
1240 ;;   180   hebrew-calendar-elapsed-days
1241 ;;   163   hebrew-calendar-last-month-of-year
1242 ;;    66   calendar-date-compare
1243 ;;    65   hebrew-calendar-days-in-year
1244 ;;    60   calendar-absolute-from-julian
1245 ;;    50   calendar-absolute-from-hebrew
1246 ;;    43   calendar-date-equal
1247 ;;    38   calendar-gregorian-from-absolute
1248 ;;     .
1249 ;;     .
1250 ;;     .
1251 ;;
1252 ;; The use of these seven macros eliminates the overhead of 92% of the function
1253 ;; calls; it's faster this way.
1254
1255 (defsubst extract-calendar-month (date)
1256   "Extract the month part of DATE which has the form (month day year)."
1257   (car date))
1258
1259 (defsubst extract-calendar-day (date)
1260   "Extract the day part of DATE which has the form (month day year)."
1261   (car (cdr date)))
1262
1263 (defsubst extract-calendar-year (date)
1264   "Extract the year part of DATE which has the form (month day year)."
1265   (car (cdr (cdr date))))
1266
1267 (defsubst calendar-leap-year-p (year)
1268   "Return t if YEAR is a Gregorian leap year."
1269   (and (zerop (% year 4))
1270        (or (not (zerop (% year 100)))
1271            (zerop (% year 400)))))
1272
1273 ;; The foregoing is a bit faster, but not as clear as the following:
1274 ;;
1275 ;;(defsubst calendar-leap-year-p (year)
1276 ;;  "Returns t if YEAR is a Gregorian leap year."
1277 ;;  (or
1278 ;;    (and (=  (% year   4) 0)
1279 ;;         (/= (% year 100) 0))
1280 ;;    (= (% year 400) 0)))
1281
1282 (defsubst calendar-last-day-of-month (month year)
1283   "The last day in MONTH during YEAR."
1284   (if (and (= month 2) (calendar-leap-year-p year))
1285       29
1286     (aref [31 28 31 30 31 30 31 31 30 31 30 31] (1- month))))
1287
1288 ;; An explanation of the calculation can be found in PascAlgorithms by
1289 ;; Edward and Ruth Reingold, Scott-Foresman/Little, Brown, 1988.
1290
1291 (defsubst calendar-day-number (date)
1292   "Return the day number within the year of the date DATE.
1293 For example, (calendar-day-number '(1 1 1987)) returns the value 1,
1294 while (calendar-day-number '(12 31 1980)) returns 366."
1295     (let* ((month (extract-calendar-month date))
1296            (day (extract-calendar-day date))
1297            (year (extract-calendar-year date))
1298          (day-of-year (+ day (* 31 (1- month)))))
1299       (if (> month 2)
1300           (progn
1301             (setq day-of-year (- day-of-year (/ (+ 23 (* 4 month)) 10)))
1302             (if (calendar-leap-year-p year)
1303                 (setq day-of-year (1+ day-of-year)))))
1304       day-of-year))
1305
1306 (defsubst calendar-absolute-from-gregorian (date)
1307   "The number of days elapsed between the Gregorian date 12/31/1 BC and DATE.
1308 The Gregorian date Sunday, December 31, 1 BC is imaginary."
1309   (let ((prior-years (1- (extract-calendar-year date))))
1310     (+ (calendar-day-number date);; Days this year
1311        (* 365 prior-years);;        + Days in prior years
1312        (/ prior-years 4);;          + Julian leap years
1313        (- (/ prior-years 100));;    - century years
1314        (/ prior-years 400))));;     + Gregorian leap years
1315
1316 (autoload 'calendar-goto-today "cal-move"
1317   "Reposition the calendar window so the current date is visible."
1318   t)
1319
1320 (autoload 'calendar-forward-month "cal-move"
1321   "Move the cursor forward ARG months."
1322   t)
1323
1324 (autoload 'calendar-forward-year "cal-move"
1325   "Move the cursor forward by ARG years."
1326   t)
1327
1328 (autoload 'calendar-backward-month "cal-move"
1329   "Move the cursor backward by ARG months."
1330   t)
1331
1332 (autoload 'calendar-backward-year "cal-move"
1333   "Move the cursor backward ARG years."
1334   t)
1335
1336 (autoload 'scroll-calendar-left "cal-move"
1337   "Scroll the displayed calendar left by ARG months."
1338   t)
1339
1340 (autoload 'scroll-calendar-right "cal-move"
1341   "Scroll the displayed calendar window right by ARG months."
1342   t)
1343
1344 (autoload 'scroll-calendar-left-three-months "cal-move"
1345   "Scroll the displayed calendar window left by 3*ARG months."
1346   t)
1347
1348 (autoload 'scroll-calendar-right-three-months "cal-move"
1349   "Scroll the displayed calendar window right by 3*ARG months."
1350   t)
1351
1352 (autoload 'calendar-cursor-to-nearest-date "cal-move"
1353   "Move the cursor to the closest date."
1354   t)
1355
1356 (autoload 'calendar-forward-day "cal-move"
1357   "Move the cursor forward ARG days."
1358   t)
1359
1360 (autoload 'calendar-backward-day "cal-move"
1361   "Move the cursor back ARG days."
1362   t)
1363
1364 (autoload 'calendar-forward-week "cal-move"
1365   "Move the cursor forward ARG weeks."
1366   t)
1367
1368 (autoload 'calendar-backward-week "cal-move"
1369   "Move the cursor back ARG weeks."
1370   t)
1371
1372 (autoload 'calendar-beginning-of-week "cal-move"
1373   "Move the cursor back ARG calendar-week-start-day's."
1374   t)
1375
1376 (autoload 'calendar-end-of-week "cal-move"
1377   "Move the cursor forward ARG calendar-week-start-day+6's."
1378   t)
1379
1380 (autoload 'calendar-beginning-of-month "cal-move"
1381   "Move the cursor backward ARG month beginnings."
1382   t)
1383
1384 (autoload 'calendar-end-of-month "cal-move"
1385   "Move the cursor forward ARG month ends."
1386   t)
1387
1388 (autoload 'calendar-beginning-of-year "cal-move"
1389   "Move the cursor backward ARG year beginnings."
1390   t)
1391
1392 (autoload 'calendar-end-of-year "cal-move"
1393   "Move the cursor forward ARG year beginnings."
1394   t)
1395
1396 (autoload 'calendar-cursor-to-visible-date "cal-move"
1397   "Move the cursor to DATE that is on the screen."
1398   t)
1399
1400 (autoload 'calendar-goto-date "cal-move"
1401   "Move cursor to DATE."
1402   t)
1403
1404 (autoload 'calendar-only-one-frame-setup "cal-x"
1405  "Start calendar and display it in a dedicated frame.")
1406
1407 (autoload 'calendar-one-frame-setup "cal-x"
1408   "Start calendar and display it in a dedicated frame together with the diary.")
1409
1410 (autoload 'calendar-two-frame-setup "cal-x"
1411   "Start calendar and diary in separate, dedicated frames.")
1412
1413 ;;;###autoload
1414 (defvar calendar-setup nil
1415   "The frame set up of the calendar.
1416 The choices are `one-frame' (calendar and diary together in one separate,
1417 dedicated frame), `two-frames' (calendar and diary in separate, dedicated
1418 frames), `calendar-only' (calendar in a separate, dedicated frame); with
1419 any other value the current frame is used.")
1420
1421 ;;;###autoload
1422 (defun calendar (&optional arg)
1423   "Choose between the one frame, two frame, or basic calendar displays.
1424 If called with an optional prefix argument, prompts for month and year.
1425
1426 The original function `calendar' has been renamed `calendar-basic-setup'.
1427 See the documentation of that function for more information."
1428   (interactive "P")
1429   (cond ((equal calendar-setup 'one-frame) (calendar-one-frame-setup arg))
1430         ((equal calendar-setup 'two-frames) (calendar-two-frame-setup arg))
1431         ((equal calendar-setup 'calendar-only)
1432          (calendar-only-one-frame-setup arg))
1433         (t (calendar-basic-setup arg))))
1434
1435 (defun calendar-basic-setup (&optional arg)
1436   "Display a three-month calendar in another window.
1437 The three months appear side by side, with the current month in the middle
1438 surrounded by the previous and next months.  The cursor is put on today's date.
1439
1440 If called with an optional prefix argument, prompts for month and year.
1441
1442 This function is suitable for execution in a .emacs file; appropriate setting
1443 of the variable `view-diary-entries-initially' will cause the diary entries for
1444 the current date to be displayed in another window.  The value of the variable
1445 `number-of-diary-entries' controls the number of days of diary entries
1446 displayed upon initial display of the calendar.
1447
1448 Once in the calendar window, future or past months can be moved into view.
1449 Arbitrary months can be displayed, or the calendar can be scrolled forward
1450 or backward.
1451
1452 The cursor can be moved forward or backward by one day, one week, one month,
1453 or one year.  All of these commands take prefix arguments which, when negative,
1454 cause movement in the opposite direction.  For convenience, the digit keys
1455 and the minus sign are automatically prefixes.  The window is replotted as
1456 necessary to display the desired date.
1457
1458 Diary entries can be marked on the calendar or displayed in another window.
1459
1460 Use \\[describe-mode] for details of the key bindings in the calendar window.
1461
1462 The Gregorian calendar is assumed.
1463
1464 After loading the calendar, the hooks given by the variable
1465 `calendar-load-hook' are run.  This is the place to add key bindings to the
1466 calendar-mode-map.
1467
1468 After preparing the calendar window initially, the hooks given by the variable
1469 `initial-calendar-window-hook' are run.
1470
1471 The hooks given by the variable `today-visible-calendar-hook' are run
1472 every time the calendar window gets scrolled, if the current date is visible
1473 in the window.  If it is not visible, the hooks given by the variable
1474 `today-invisible-calendar-hook' are run.  Thus, for example, setting
1475 `today-visible-calendar-hook' to 'calendar-star-date will cause today's date
1476 to be replaced by asterisks to highlight it whenever it is in the window."
1477   (interactive "P")
1478   (set-buffer (get-buffer-create calendar-buffer))
1479   (calendar-mode)
1480   (let* ((pop-up-windows t)
1481          (split-height-threshold 1000)
1482          (date (if arg
1483                    (calendar-read-date t)
1484                  (calendar-current-date)))
1485          (month (extract-calendar-month date))
1486          (year (extract-calendar-year date)))
1487     (pop-to-buffer calendar-buffer)
1488     (increment-calendar-month month year (- calendar-offset))
1489     (generate-calendar-window month year)
1490     (if (and view-diary-entries-initially (calendar-date-is-visible-p date))
1491         (view-diary-entries
1492          (if (vectorp number-of-diary-entries)
1493              (aref number-of-diary-entries (calendar-day-of-week date))
1494            number-of-diary-entries))))
1495   (let* ((diary-buffer (get-file-buffer diary-file))
1496          (diary-window (if diary-buffer (get-buffer-window diary-buffer)))
1497          (split-height-threshold (if diary-window 2 1000)))
1498     (if view-calendar-holidays-initially
1499         (list-calendar-holidays)))
1500   (run-hooks 'initial-calendar-window-hook))
1501
1502 (autoload 'view-diary-entries "diary-lib"
1503   "Prepare and display a buffer with diary entries.
1504 Searches your diary file for entries that match ARG days starting with
1505 the date indicated by the cursor position in the displayed three-month
1506 calendar."
1507   t)
1508
1509 (autoload 'calendar-sunrise-sunset "solar"
1510   "Local time of sunrise and sunset for date under cursor."
1511   t)
1512
1513 (autoload 'calendar-phases-of-moon "lunar"
1514   "Create a buffer of the phases of the moon for the current calendar window."
1515   t)
1516
1517 (autoload 'calendar-print-french-date "cal-french"
1518   "Show the French Revolutionary calendar equivalent of the date under the cursor."
1519   t)
1520
1521 (autoload 'calendar-goto-french-date "cal-french"
1522  "Move cursor to French Revolutionary date."
1523   t)
1524
1525 (autoload 'calendar-french-date-string "cal-french"
1526   "String of French Revolutionary date of Gregorian date."
1527   t)
1528
1529 (autoload 'calendar-mayan-date-string "cal-mayan"
1530   "String of Mayan date of Gregorian date."
1531   t)
1532
1533 (autoload 'calendar-print-mayan-date "cal-mayan"
1534   "Show the Mayan long count, Tzolkin, and Haab equivalents of the date under the cursor."
1535   t)
1536
1537 (autoload 'calendar-goto-mayan-long-count-date "cal-mayan"
1538  "Move cursor to Mayan long count date."
1539   t)
1540
1541 (autoload 'calendar-next-haab-date "cal-mayan"
1542   "Move cursor to next instance of Mayan Haab date."
1543   t)
1544
1545 (autoload 'calendar-previous-haab-date "cal-mayan"
1546   "Move cursor to previous instance of Mayan Haab date."
1547   t)
1548
1549 (autoload 'calendar-next-tzolkin-date "cal-mayan"
1550   "Move cursor to next instance of Mayan Tzolkin date."
1551   t)
1552
1553 (autoload 'calendar-previous-tzolkin-date "cal-mayan"
1554   "Move cursor to previous instance of Mayan Tzolkin date."
1555   t)
1556
1557 (autoload 'calendar-next-calendar-round-date "cal-mayan"
1558   "Move cursor to next instance of Mayan Haab/Tzolkin combination."
1559   t)
1560
1561 (autoload 'calendar-previous-calendar-round-date "cal-mayan"
1562   "Move cursor to previous instance of Mayan Haab/Tzolkin combination."
1563   t)
1564
1565 (autoload 'calendar-goto-chinese-date "cal-china"
1566    "Move cursor to Chinese date."
1567    t)
1568
1569 (autoload 'calendar-print-chinese-date "cal-china"
1570  "Show the Chinese date equivalents of date."
1571  t)
1572
1573 (autoload 'calendar-chinese-date-string "cal-china"
1574   "String of Chinese date of Gregorian date."
1575   t)
1576
1577 (autoload 'calendar-absolute-from-astro  "cal-julian"
1578   "Absolute date of astronomical (Julian) day number D."
1579   t )
1580
1581 (autoload 'calendar-astro-from-absolute "cal-julian"
1582   "Astronomical (Julian) day number of absolute date D.")
1583
1584 (autoload 'calendar-astro-date-string "cal-julian"
1585   "String of astronomical (Julian) day number of Gregorian date."
1586   t)
1587
1588 (autoload 'calendar-goto-astro-day-number "cal-julian"
1589    "Move cursor to astronomical (Julian) day number."
1590    t)
1591
1592 (autoload 'calendar-print-astro-day-number "cal-julian"
1593    "Show the astro date equivalents of date."
1594    t)
1595
1596 (autoload 'calendar-julian-from-absolute "cal-julian"
1597   "Compute the Julian (month day year) corresponding to the absolute DATE.
1598 The absolute date is the number of days elapsed since the (imaginary)
1599 Gregorian date Sunday, December 31, 1 BC.")
1600
1601 (autoload 'calendar-goto-julian-date "cal-julian"
1602   "Move cursor to Julian DATE; echo Julian date unless NOECHO is t."
1603   t)
1604
1605 (autoload 'calendar-print-julian-date "cal-julian"
1606   "Show the Julian calendar equivalent of the date under the cursor."
1607   t)
1608
1609 (autoload 'calendar-julian-date-string "cal-julian"
1610   "String of Julian date of Gregorian DATE.
1611 Defaults to today's date if DATE is not given.
1612 Driven by the variable `calendar-date-display-form'.")
1613
1614 (autoload 'calendar-goto-iso-date "cal-iso"
1615   "Move cursor to ISO date."
1616   t)
1617
1618 (autoload 'calendar-print-iso-date "cal-iso"
1619   "Show the ISO date equivalents of date."
1620   t)
1621
1622 (autoload 'calendar-iso-date-string "cal-iso"
1623   "String of ISO date of Gregorian date."
1624   t)
1625
1626 (autoload 'calendar-goto-islamic-date "cal-islam"
1627   "Move cursor to Islamic date."
1628   t)
1629
1630 (autoload 'calendar-print-islamic-date "cal-islam"
1631   "Show the Islamic date equivalents of date."
1632   t)
1633
1634 (autoload 'calendar-islamic-date-string "cal-islam"
1635   "String of Islamic date of Gregorian date."
1636   t)
1637
1638 (autoload 'calendar-goto-hebrew-date "cal-hebrew"
1639   "Move cursor to Hebrew date date."
1640   t)
1641
1642 (autoload 'calendar-print-hebrew-date "cal-hebrew"
1643   "Show the Hebrew date equivalents of date."
1644   t)
1645
1646 (autoload 'calendar-hebrew-date-string "cal-hebrew"
1647   "String of Hebrew date of Gregorian date."
1648   t)
1649
1650 (autoload 'calendar-goto-coptic-date "cal-coptic"
1651    "Move cursor to Coptic date date."
1652    t)
1653
1654 (autoload 'calendar-print-coptic-date "cal-coptic"
1655  "Show the Coptic date equivalents of date."
1656  t)
1657
1658 (autoload 'calendar-coptic-date-string "cal-coptic"
1659   "String of Coptic date of Gregorian date."
1660   t)
1661
1662 (autoload 'calendar-goto-ethiopic-date "cal-coptic"
1663    "Move cursor to Ethiopic date date."
1664    t)
1665
1666 (autoload 'calendar-print-ethiopic-date "cal-coptic"
1667  "Show the Ethiopic date equivalents of date."
1668  t)
1669
1670 (autoload 'calendar-ethiopic-date-string "cal-coptic"
1671   "String of Ethiopic date of Gregorian date."
1672   t)
1673
1674 (autoload 'calendar-goto-persian-date "cal-persia"
1675    "Move cursor to Persian date date."
1676    t)
1677
1678 (autoload 'calendar-print-persian-date "cal-persia"
1679  "Show the Persian date equivalents of date."
1680  t)
1681
1682 (autoload 'calendar-persian-date-string "cal-persia"
1683   "String of Persian date of Gregorian date."
1684   t)
1685
1686 (autoload 'show-all-diary-entries "diary-lib"
1687   "Show all of the diary entries in the diary file.
1688 This function gets rid of the selective display of the diary file so that
1689 all entries, not just some, are visible.  If there is no diary buffer, one
1690 is created."
1691   t)
1692
1693 (autoload 'mark-diary-entries "diary-lib"
1694   "Mark days in the calendar window that have diary entries.
1695 Each entry in diary file visible in the calendar window is marked."
1696   t)
1697
1698 (autoload 'make-diary-entry "diary-lib"
1699   "Insert a diary entry STRING which may be NONMARKING in FILE."
1700   t)
1701
1702 (autoload 'insert-diary-entry "diary-lib"
1703   "Insert a diary entry for the date indicated by point."
1704   t)
1705
1706 (autoload 'insert-weekly-diary-entry "diary-lib"
1707   "Insert a weekly diary entry for the day of the week indicated by point."
1708   t)
1709
1710
1711 (autoload 'insert-monthly-diary-entry "diary-lib"
1712   "Insert a monthly diary entry for the day of the month indicated by point."
1713   t)
1714
1715 (autoload 'insert-yearly-diary-entry "diary-lib"
1716   "Insert an annual diary entry for the day of the year indicated by point."
1717   t)
1718
1719 (autoload 'insert-anniversary-diary-entry "diary-lib"
1720   "Insert an anniversary diary entry for the date indicated by point."
1721   t)
1722
1723 (autoload 'insert-block-diary-entry "diary-lib"
1724   "Insert a block diary entry for the dates indicated by point and mark."
1725   t)
1726
1727 (autoload 'insert-cyclic-diary-entry "diary-lib"
1728   "Insert a cyclic diary entry starting at the date indicated by point."
1729   t)
1730
1731 (autoload 'insert-hebrew-diary-entry "cal-hebrew"
1732   "Insert a diary entry for the Hebrew date corresponding to the date
1733 indicated by point."
1734   t)
1735
1736 (autoload 'insert-monthly-hebrew-diary-entry "cal-hebrew"
1737   "Insert a monthly diary entry for the day of the Hebrew month corresponding
1738 to the date indicated by point."
1739   t)
1740
1741 (autoload 'insert-yearly-hebrew-diary-entry "cal-hebrew"
1742   "Insert an annual diary entry for the day of the Hebrew year corresponding
1743 to the date indicated by point."
1744   t)
1745
1746 (autoload 'insert-islamic-diary-entry "cal-islam"
1747   "Insert a diary entry for the Islamic date corresponding to the date
1748 indicated by point."
1749   t)
1750
1751 (autoload 'insert-monthly-islamic-diary-entry "cal-islam"
1752   "Insert a monthly diary entry for the day of the Islamic month corresponding
1753 to the date indicated by point."
1754   t)
1755
1756 (autoload 'insert-yearly-islamic-diary-entry "cal-islam"
1757   "Insert an annual diary entry for the day of the Islamic year corresponding
1758 to the date indicated by point."
1759   t)
1760
1761 (autoload 'list-calendar-holidays "holidays"
1762   "Create a buffer containing the holidays for the current calendar window.
1763 The holidays are those in the list `calendar-notable-days'.  Returns t if any
1764 holidays are found, nil if not."
1765   t)
1766
1767 (autoload 'cal-tex-cursor-month "cal-tex"
1768   "Make a buffer with LaTeX commands for the month cursor is on.
1769 Optional prefix argument specifies number of months to be produced.
1770 Calendar is condensed onto one page.")
1771
1772 (autoload 'cal-tex-cursor-month-landscape "cal-tex"
1773   "Make a buffer with LaTeX commands for the month cursor is on.
1774 Optional prefix argument specifies number of months to be produced.")
1775
1776 (autoload 'cal-tex-cursor-day "cal-tex"
1777   "Make a buffer with LaTeX commands for the day cursor is on.")
1778
1779 (autoload 'cal-tex-cursor-week "cal-tex"
1780   "Make a buffer with LaTeX commands for a two-page one-week calendar.
1781 It applies to the week that point is in.
1782 Optional prefix argument specifies number of weeks.
1783 Holidays are included if `cal-tex-holidays' is t.")
1784
1785 (autoload 'cal-tex-cursor-week2 "cal-tex"
1786   "Make a buffer with LaTeX commands for a two-page one-week calendar.
1787 It applies to the week that point is in.
1788 Optional prefix argument specifies number of weeks.
1789 Holidays are included if `cal-tex-holidays' is t.")
1790
1791 (autoload 'cal-tex-cursor-week-iso "cal-tex"
1792   "Make a buffer with LaTeX commands for a one page ISO-style weekly calendar.
1793 Optional prefix argument specifies number of weeks.
1794 Diary entries are included if `cal-tex-diary' is t.
1795 Holidays are included if `cal-tex-holidays' is t.")
1796
1797 (autoload 'cal-tex-cursor-week-monday "cal-tex"
1798   "Make a buffer with LaTeX commands for a two-page one-week calendar.
1799 It applies to the week that point is in, and starts on Monday.
1800 Optional prefix argument specifies number of weeks.
1801 Holidays are included if `cal-tex-holidays' is t.")
1802
1803 (autoload 'cal-tex-cursor-filofax-2week "cal-tex"
1804   "Two-weeks-at-a-glance Filofax style calendar for week indicated by cursor.
1805 Optional prefix argument specifies number of weeks.
1806 Diary entries are included if cal-tex-diary is t.
1807 Holidays are included if `cal-tex-holidays' is t.")
1808
1809 (autoload 'cal-tex-cursor-filofax-week "cal-tex"
1810   "One-week-at-a-glance Filofax style calendar for week indicated by cursor.
1811 Optional prefix argument specifies number of weeks.
1812 Weeks start on Monday.
1813 Diary entries are included if cal-tex-diary is t.
1814 Holidays are included if `cal-tex-holidays' is t.")
1815
1816 (autoload 'cal-tex-cursor-filofax-daily "cal-tex"
1817   "Day-per-page Filofax style calendar for week indicated by cursor.
1818 Optional prefix argument specifies number of weeks.  Weeks start on Monday.
1819 Diary entries are included if `cal-tex-diary' is t.
1820 Holidays are included if `cal-tex-holidays' is t.")
1821
1822 (autoload 'cal-tex-cursor-year "cal-tex"
1823   "Make a buffer with LaTeX commands for a year's calendar.
1824 Optional prefix argument specifies number of years.")
1825
1826 (autoload 'cal-tex-cursor-year-landscape "cal-tex"
1827   "Make a buffer with LaTeX commands for a year's calendar (landscape).
1828 Optional prefix argument specifies number of years.")
1829
1830 (autoload 'cal-tex-cursor-filofax-year "cal-tex"
1831   "Make a buffer with LaTeX commands for a year's calendar (Filofax).
1832 Optional prefix argument specifies number of years.")
1833
1834 (autoload 'mark-calendar-holidays "holidays"
1835   "Mark notable days in the calendar window."
1836   t)
1837
1838 (autoload 'calendar-cursor-holidays "holidays"
1839   "Find holidays for the date specified by the cursor in the calendar window."
1840   t)
1841
1842 (defun generate-calendar-window (&optional mon yr)
1843   "Generate the calendar window for the current date.
1844 Or, for optional MON, YR."
1845   (let* ((buffer-read-only nil)
1846          (today (calendar-current-date))
1847          (month (extract-calendar-month today))
1848          (day (extract-calendar-day today))
1849          (year (extract-calendar-year today))
1850          (today-visible
1851           (or (not mon)
1852               (let ((offset (calendar-interval mon yr month year)))
1853                 (and (<= offset 1) (>= offset -1)))))
1854          (day-in-week (calendar-day-of-week today)))
1855     (update-calendar-mode-line)
1856     (if mon
1857         (generate-calendar mon yr)
1858         (generate-calendar month year))
1859     (calendar-cursor-to-visible-date
1860      (if today-visible today (list displayed-month 1 displayed-year)))
1861     (set-buffer-modified-p nil)
1862     (if (or (one-window-p t) (/= (frame-width) (window-width)))
1863         ;; Don't mess with the window size, but ensure that the first
1864         ;; line is fully visible
1865         (set-window-vscroll nil 0)
1866       ;; Adjust the window to exactly fit the displayed calendar
1867       (fit-window-to-buffer))
1868     (sit-for 0)
1869     (if (and (boundp 'font-lock-mode)
1870              font-lock-mode)
1871         (font-lock-fontify-buffer))
1872     (and mark-holidays-in-calendar
1873          (mark-calendar-holidays)
1874          (sit-for 0))
1875     (unwind-protect
1876         (if mark-diary-entries-in-calendar (mark-diary-entries))
1877       (if today-visible
1878           (run-hooks 'today-visible-calendar-hook)
1879         (run-hooks 'today-invisible-calendar-hook)))))
1880
1881 (defun generate-calendar (month year)
1882   "Generate a three-month Gregorian calendar centered around MONTH, YEAR."
1883   (if (< (+ month (* 12 (1- year))) 2)
1884       (error "Months before February, 1 AD are not available"))
1885   (setq displayed-month month)
1886   (setq displayed-year year)
1887   (erase-buffer)
1888   (increment-calendar-month month year -1)
1889   (calendar-for-loop i from 0 to 2 do
1890        (generate-calendar-month month year (+ 5 (* 25 i)))
1891        (increment-calendar-month month year 1)))
1892
1893 (defun generate-calendar-month (month year indent)
1894   "Produce a calendar for MONTH, YEAR on the Gregorian calendar.
1895 The calendar is inserted at the top of the buffer in which point is currently
1896 located, but indented INDENT spaces.  The indentation is done from the first
1897 character on the line and does not disturb the first INDENT characters on the
1898 line."
1899   (let* ((blank-days;; at start of month
1900           (mod
1901            (- (calendar-day-of-week (list month 1 year))
1902               calendar-week-start-day)
1903            7))
1904          (last (calendar-last-day-of-month month year)))
1905    (goto-char (point-min))
1906    (calendar-insert-indented
1907     (calendar-string-spread
1908      (list (format "%s %d" (calendar-month-name month) year)) ?  20)
1909     indent t)
1910    (calendar-insert-indented "" indent);; Go to proper spot
1911    ;; Use the first two characters of each day to head the columns.
1912    (calendar-for-loop i from 0 to 6 do
1913       (insert
1914        (let ((string
1915               (calendar-day-name (mod (+ calendar-week-start-day i) 7) nil t)))
1916          (if enable-multibyte-characters
1917              (truncate-string-to-width string 2)
1918            (substring string 0 2)))
1919        " "))
1920    (calendar-insert-indented "" 0 t);; Force onto following line
1921    (calendar-insert-indented "" indent);; Go to proper spot
1922    ;; Add blank days before the first of the month
1923    (calendar-for-loop i from 1 to blank-days do (insert "   "))
1924    ;; Put in the days of the month
1925    (calendar-for-loop i from 1 to last do
1926       (insert (format "%2d " i))
1927       (add-text-properties
1928        (- (point) 3) (1- (point))
1929        '(mouse-face highlight
1930          help-echo "mouse-2: menu of operations for this date"))
1931       (and (zerop (mod (+ i blank-days) 7))
1932            (/= i last)
1933            (calendar-insert-indented "" 0 t)    ;; Force onto following line
1934            (calendar-insert-indented "" indent)))));; Go to proper spot
1935
1936 (defun calendar-insert-indented (string indent &optional newline)
1937   "Insert STRING at column INDENT.
1938 If the optional parameter NEWLINE is t, leave point at start of next line,
1939 inserting a newline if there was no next line; otherwise, leave point after
1940 the inserted text.  Value is always t."
1941   ;; Try to move to that column.
1942   (move-to-column indent)
1943   ;; If line is too short, indent out to that column.
1944   (if (< (current-column) indent)
1945       (indent-to indent))
1946   (insert string)
1947   ;; Advance to next line, if requested.
1948   (if newline
1949       (progn
1950         (end-of-line)
1951         (if (eobp)
1952             (newline)
1953           (forward-line 1))))
1954   t)
1955
1956 (defun redraw-calendar ()
1957   "Redraw the calendar display."
1958   (interactive)
1959   (let ((cursor-date (calendar-cursor-to-nearest-date)))
1960     (generate-calendar-window displayed-month displayed-year)
1961     (calendar-cursor-to-visible-date cursor-date)))
1962
1963 (defcustom calendar-debug-sexp nil
1964   "*Turn debugging on when evaluating a sexp in the diary or holiday list."
1965   :type 'boolean
1966   :group 'calendar)
1967
1968 (defvar calendar-mode-map nil)
1969 (if calendar-mode-map
1970     nil
1971   (setq calendar-mode-map (make-sparse-keymap))
1972   (require 'cal-menu)
1973   (calendar-for-loop i from 0 to 9 do
1974        (define-key calendar-mode-map (int-to-string i) 'digit-argument))
1975   (let ((l (list 'narrow-to-region 'mark-word 'mark-sexp 'mark-paragraph
1976                  'mark-defun 'mark-whole-buffer 'mark-page
1977                  'downcase-region 'upcase-region 'kill-region
1978                  'copy-region-as-kill 'capitalize-region 'write-region)))
1979     (while l
1980       (substitute-key-definition (car l) 'calendar-not-implemented
1981                                  calendar-mode-map global-map)
1982       (setq l (cdr l))))
1983   (define-key calendar-mode-map "-"     'negative-argument)
1984   (define-key calendar-mode-map "\C-x>" 'scroll-calendar-right)
1985   (define-key calendar-mode-map [prior] 'scroll-calendar-right-three-months)
1986   (define-key calendar-mode-map "\ev"   'scroll-calendar-right-three-months)
1987   (define-key calendar-mode-map "\C-x<" 'scroll-calendar-left)
1988   (define-key calendar-mode-map [next]  'scroll-calendar-left-three-months)
1989   (define-key calendar-mode-map "\C-v"  'scroll-calendar-left-three-months)
1990   (define-key calendar-mode-map "\C-b"  'calendar-backward-day)
1991   (define-key calendar-mode-map "\C-p"  'calendar-backward-week)
1992   (define-key calendar-mode-map "\e{"   'calendar-backward-month)
1993   (define-key calendar-mode-map "\C-x[" 'calendar-backward-year)
1994   (define-key calendar-mode-map "\C-f"  'calendar-forward-day)
1995   (define-key calendar-mode-map "\C-n"  'calendar-forward-week)
1996   (define-key calendar-mode-map [left]  'calendar-backward-day)
1997   (define-key calendar-mode-map [up]    'calendar-backward-week)
1998   (define-key calendar-mode-map [right] 'calendar-forward-day)
1999   (define-key calendar-mode-map [down]  'calendar-forward-week)
2000   (define-key calendar-mode-map "\e}"   'calendar-forward-month)
2001   (define-key calendar-mode-map "\C-x]" 'calendar-forward-year)
2002   (define-key calendar-mode-map "\C-a"  'calendar-beginning-of-week)
2003   (define-key calendar-mode-map "\C-e"  'calendar-end-of-week)
2004   (define-key calendar-mode-map "\ea"   'calendar-beginning-of-month)
2005   (define-key calendar-mode-map "\ee"   'calendar-end-of-month)
2006   (define-key calendar-mode-map "\e<"   'calendar-beginning-of-year)
2007   (define-key calendar-mode-map "\e>"   'calendar-end-of-year)
2008   (define-key calendar-mode-map "\C-@"  'calendar-set-mark)
2009   ;; Many people are used to typing C-SPC and getting C-@.
2010   (define-key calendar-mode-map [?\C- ] 'calendar-set-mark)
2011   (define-key calendar-mode-map "\C-x\C-x" 'calendar-exchange-point-and-mark)
2012   (define-key calendar-mode-map "\e=" 'calendar-count-days-region)
2013   (define-key calendar-mode-map "gd"  'calendar-goto-date)
2014   (define-key calendar-mode-map "gj"  'calendar-goto-julian-date)
2015   (define-key calendar-mode-map "ga"  'calendar-goto-astro-day-number)
2016   (define-key calendar-mode-map "gh"  'calendar-goto-hebrew-date)
2017   (define-key calendar-mode-map "gi"  'calendar-goto-islamic-date)
2018   (define-key calendar-mode-map "gC"  'calendar-goto-chinese-date)
2019   (define-key calendar-mode-map "gk"  'calendar-goto-coptic-date)
2020   (define-key calendar-mode-map "ge"  'calendar-goto-ethiopic-date)
2021   (define-key calendar-mode-map "gp"  'calendar-goto-persian-date)
2022   (define-key calendar-mode-map "gc"  'calendar-goto-iso-date)
2023   (define-key calendar-mode-map "gf"  'calendar-goto-french-date)
2024   (define-key calendar-mode-map "gml"  'calendar-goto-mayan-long-count-date)
2025   (define-key calendar-mode-map "gmpc" 'calendar-previous-calendar-round-date)
2026   (define-key calendar-mode-map "gmnc" 'calendar-next-calendar-round-date)
2027   (define-key calendar-mode-map "gmph" 'calendar-previous-haab-date)
2028   (define-key calendar-mode-map "gmnh" 'calendar-next-haab-date)
2029   (define-key calendar-mode-map "gmpt" 'calendar-previous-tzolkin-date)
2030   (define-key calendar-mode-map "gmnt" 'calendar-next-tzolkin-date)
2031   (define-key calendar-mode-map "Aa"   'appt-add)
2032   (define-key calendar-mode-map "Ad"   'appt-delete)
2033   (define-key calendar-mode-map "S"   'calendar-sunrise-sunset)
2034   (define-key calendar-mode-map "M"   'calendar-phases-of-moon)
2035   (define-key calendar-mode-map " "   'scroll-other-window)
2036   (define-key calendar-mode-map "\C-c\C-l" 'redraw-calendar)
2037   (define-key calendar-mode-map "."   'calendar-goto-today)
2038   (define-key calendar-mode-map "o"   'calendar-other-month)
2039   (define-key calendar-mode-map "q"   'exit-calendar)
2040   (define-key calendar-mode-map "a"   'list-calendar-holidays)
2041   (define-key calendar-mode-map "h"   'calendar-cursor-holidays)
2042   (define-key calendar-mode-map "x"   'mark-calendar-holidays)
2043   (define-key calendar-mode-map "u"   'calendar-unmark)
2044   (define-key calendar-mode-map "m"   'mark-diary-entries)
2045   (define-key calendar-mode-map "d"   'view-diary-entries)
2046   (define-key calendar-mode-map "D"   'view-other-diary-entries)
2047   (define-key calendar-mode-map "s"   'show-all-diary-entries)
2048   (define-key calendar-mode-map "pd"  'calendar-print-day-of-year)
2049   (define-key calendar-mode-map "pC"  'calendar-print-chinese-date)
2050   (define-key calendar-mode-map "pk"  'calendar-print-coptic-date)
2051   (define-key calendar-mode-map "pe"  'calendar-print-ethiopic-date)
2052   (define-key calendar-mode-map "pp"  'calendar-print-persian-date)
2053   (define-key calendar-mode-map "pc"  'calendar-print-iso-date)
2054   (define-key calendar-mode-map "pj"  'calendar-print-julian-date)
2055   (define-key calendar-mode-map "pa"  'calendar-print-astro-day-number)
2056   (define-key calendar-mode-map "ph"  'calendar-print-hebrew-date)
2057   (define-key calendar-mode-map "pi"  'calendar-print-islamic-date)
2058   (define-key calendar-mode-map "pf"  'calendar-print-french-date)
2059   (define-key calendar-mode-map "pm"  'calendar-print-mayan-date)
2060   (define-key calendar-mode-map "po"  'calendar-print-other-dates)
2061   (define-key calendar-mode-map "id"  'insert-diary-entry)
2062   (define-key calendar-mode-map "iw"  'insert-weekly-diary-entry)
2063   (define-key calendar-mode-map "im"  'insert-monthly-diary-entry)
2064   (define-key calendar-mode-map "iy"  'insert-yearly-diary-entry)
2065   (define-key calendar-mode-map "ia"  'insert-anniversary-diary-entry)
2066   (define-key calendar-mode-map "ib"  'insert-block-diary-entry)
2067   (define-key calendar-mode-map "ic"  'insert-cyclic-diary-entry)
2068   (define-key calendar-mode-map "ihd" 'insert-hebrew-diary-entry)
2069   (define-key calendar-mode-map "ihm" 'insert-monthly-hebrew-diary-entry)
2070   (define-key calendar-mode-map "ihy" 'insert-yearly-hebrew-diary-entry)
2071   (define-key calendar-mode-map "iid" 'insert-islamic-diary-entry)
2072   (define-key calendar-mode-map "iim" 'insert-monthly-islamic-diary-entry)
2073   (define-key calendar-mode-map "iiy" 'insert-yearly-islamic-diary-entry)
2074   (define-key calendar-mode-map "?"   'calendar-goto-info-node)
2075   (define-key calendar-mode-map "tm" 'cal-tex-cursor-month)
2076   (define-key calendar-mode-map "tM" 'cal-tex-cursor-month-landscape)
2077   (define-key calendar-mode-map "td" 'cal-tex-cursor-day)
2078   (define-key calendar-mode-map "tw1" 'cal-tex-cursor-week)
2079   (define-key calendar-mode-map "tw2" 'cal-tex-cursor-week2)
2080   (define-key calendar-mode-map "tw3" 'cal-tex-cursor-week-iso)
2081   (define-key calendar-mode-map "tw4" 'cal-tex-cursor-week-monday)
2082   (define-key calendar-mode-map "tfd" 'cal-tex-cursor-filofax-daily)
2083   (define-key calendar-mode-map "tfw" 'cal-tex-cursor-filofax-2week)
2084   (define-key calendar-mode-map "tfW" 'cal-tex-cursor-filofax-week)
2085   (define-key calendar-mode-map "tfy" 'cal-tex-cursor-filofax-year)
2086   (define-key calendar-mode-map "ty" 'cal-tex-cursor-year)
2087   (define-key calendar-mode-map "tY" 'cal-tex-cursor-year-landscape))
2088
2089 (defun describe-calendar-mode ()
2090   "Create a help buffer with a brief description of the `calendar-mode'."
2091   (interactive)
2092   (with-output-to-temp-buffer "*Help*"
2093     (princ
2094      (format
2095       "Calendar Mode:\nFor a complete description, type %s\n%s\n"
2096       (substitute-command-keys
2097        "\\<calendar-mode-map>\\[describe-mode] from within the calendar")
2098       (substitute-command-keys "\\{calendar-mode-map}")))
2099     (save-excursion
2100       (set-buffer standard-output)
2101       (help-mode))
2102     (print-help-return-message)))
2103
2104 ;; Calendar mode is suitable only for specially formatted data.
2105 (put 'calendar-mode 'mode-class 'special)
2106
2107 (defvar calendar-mode-line-format
2108   (list
2109    (propertize (substitute-command-keys
2110                 "\\<calendar-mode-map>\\[scroll-calendar-left]")
2111                'help-echo "mouse-2: scroll left"
2112                'keymap (make-mode-line-mouse-map 'mouse-2
2113                                                  'mouse-scroll-calendar-left))
2114    "Calendar"
2115    (concat
2116     (propertize
2117      (substitute-command-keys
2118       "\\<calendar-mode-map>\\[calendar-goto-info-node] info")
2119      'help-echo "mouse-2: read Info on Calendar"
2120      'keymap (make-mode-line-mouse-map 'mouse-2 'calendar-goto-info-node))
2121     "/"
2122     (propertize
2123      (substitute-command-keys
2124      "\\<calendar-mode-map>\\[calendar-other-month] other")
2125      'help-echo "mouse-2: choose another month"
2126      'keymap (make-mode-line-mouse-map
2127               'mouse-2 'mouse-calendar-other-month))
2128     "/"
2129     (propertize
2130      (substitute-command-keys
2131      "\\<calendar-mode-map>\\[calendar-goto-today] today")
2132      'help-echo "mouse-2: go to today's date"
2133      'keymap (make-mode-line-mouse-map 'mouse-2 #'calendar-goto-today)))
2134    '(calendar-date-string (calendar-current-date) t)
2135    (propertize (substitute-command-keys
2136                 "\\<calendar-mode-map>\\[scroll-calendar-right]")
2137                'help-echo "mouse-2: scroll right"
2138                'keymap (make-mode-line-mouse-map
2139                         'mouse-2 'mouse-scroll-calendar-right)))
2140   "The mode line of the calendar buffer.
2141
2142 This must be a list of items that evaluate to strings--those strings are
2143 evaluated and concatenated together, evenly separated by blanks.  The variable
2144 `date' is available for use as the date under (or near) the cursor; `date'
2145 defaults to the current date if it is otherwise undefined.  Here is an example
2146 value that has the Hebrew date, the day number/days remaining in the year,
2147 and the ISO week/year numbers in the mode.  When calendar-move-hook is set to
2148 'update-calendar-mode-line, these mode line shows these values for the date
2149 under the cursor:
2150
2151       (list
2152        \"\"
2153        '(calendar-hebrew-date-string date)
2154        '(let* ((year (extract-calendar-year date))
2155                (d (calendar-day-number date))
2156                (days-remaining
2157                 (- (calendar-day-number (list 12 31 year)) d)))
2158           (format \"%d/%d\" d days-remaining))
2159        '(let* ((d (calendar-absolute-from-gregorian date))
2160                (iso-date (calendar-iso-from-absolute d)))
2161           (format \"ISO week %d of %d\"
2162             (extract-calendar-month iso-date)
2163             (extract-calendar-year iso-date)))
2164        \"\"))
2165 ")
2166
2167 (defun mouse-scroll-calendar-left (event)
2168   "Scroll the displayed calendar left by one month.
2169 Maintains the relative position of the cursor
2170 with respect to the calendar as well as possible."
2171   (interactive "e")
2172   (save-selected-window
2173     (select-window (posn-window (event-start event)))
2174     (scroll-calendar-left 1)))
2175
2176 (defun mouse-scroll-calendar-right (event)
2177   "Scroll the displayed calendar right by one month.
2178 Maintains the relative position of the cursor
2179 with respect to the calendar as well as possible."
2180   (interactive "e")
2181   (save-selected-window
2182     (select-window (posn-window (event-start event)))
2183     (scroll-calendar-right 1)))
2184
2185 (defun mouse-calendar-other-month (event)
2186   "Display a three-month calendar centered around a specified month and year."
2187   (interactive "e")
2188   (save-selected-window
2189     (select-window (posn-window (event-start event)))
2190     (call-interactively 'calendar-other-month)))
2191
2192 (defun calendar-goto-info-node ()
2193   "Go to the info node for the calendar."
2194   (interactive)
2195   (require 'info)
2196   (let ((where (save-window-excursion
2197                  (Info-find-emacs-command-nodes 'calendar))))
2198     (if (not where)
2199         (error "Couldn't find documentation for the calendar")
2200       (let (same-window-buffer-names)
2201         (info))
2202       (Info-find-node (car (car where)) (car (cdr (car where)))))))
2203
2204
2205
2206 (defun calendar-mode ()
2207   "A major mode for the calendar window.
2208
2209 For a complete description, type \
2210 \\<calendar-mode-map>\\[calendar-goto-info-node] from within the calendar.
2211
2212 \\<calendar-mode-map>\\{calendar-mode-map}"
2213
2214   (kill-all-local-variables)
2215   (setq major-mode 'calendar-mode)
2216   (setq mode-name "Calendar")
2217   (use-local-map calendar-mode-map)
2218   (setq buffer-read-only t)
2219   (setq indent-tabs-mode nil)
2220   (update-calendar-mode-line)
2221   (add-hook 'activate-menubar-hook 'cal-menu-update nil t)
2222   (make-local-variable 'calendar-mark-ring)
2223   (make-local-variable 'displayed-month);;  Month in middle of window.
2224   (make-local-variable 'displayed-year) ;;  Year in middle of window.
2225   (set (make-local-variable 'font-lock-defaults)
2226        '(calendar-font-lock-keywords t)))
2227
2228 (defun calendar-string-spread (strings char length)
2229   "Concatenate list of STRINGS separated with copies of CHAR to fill LENGTH.
2230 The effect is like mapconcat but the separating pieces are as balanced as
2231 possible.  Each item of STRINGS is evaluated before concatenation so it can
2232 actually be an expression that evaluates to a string.  If LENGTH is too short,
2233 the STRINGS are just concatenated and the result truncated."
2234 ;; The algorithm is based on equation (3.25) on page 85 of Concrete
2235 ;; Mathematics by Ronald L. Graham, Donald E. Knuth, and Oren Patashnik,
2236 ;; Addison-Wesley, Reading, MA, 1989
2237   (let* ((strings (mapcar 'eval
2238                           (if (< (length strings) 2)
2239                               (append (list "") strings (list ""))
2240                             strings)))
2241          (n (- length (length (apply 'concat strings))))
2242          (m (1- (length strings)))
2243          (s (car strings))
2244          (strings (cdr strings))
2245          (i 0))
2246     (while strings
2247       (setq s (concat s
2248                       (make-string (max 0 (/ (+ n i) m)) char)
2249                       (car strings)))
2250       (setq i (1+ i))
2251       (setq strings (cdr strings)))
2252     (substring s 0 length)))
2253
2254 (defun update-calendar-mode-line ()
2255   "Update the calendar mode line with the current date and date style."
2256   (if (bufferp (get-buffer calendar-buffer))
2257       (save-excursion
2258         (set-buffer calendar-buffer)
2259         (setq mode-line-format
2260               (calendar-string-spread
2261                (let ((date (condition-case nil
2262                                (calendar-cursor-to-nearest-date)
2263                              (error (calendar-current-date)))))
2264                  (mapcar 'eval  calendar-mode-line-format))
2265                ?  (frame-width)))
2266         (force-mode-line-update))))
2267
2268 (defun calendar-window-list ()
2269   "List of all calendar-related windows."
2270   (let ((calendar-buffers (calendar-buffer-list))
2271         list)
2272     (walk-windows (lambda (w)
2273                     (if (memq (window-buffer w) calendar-buffers)
2274                         (setq list (cons w list))))
2275                   nil t)
2276     list))
2277
2278 (defun calendar-buffer-list ()
2279   "List of all calendar-related buffers."
2280   (let* ((diary-buffer (get-file-buffer diary-file))
2281          (buffers (list "*Yahrzeits*" lunar-phases-buffer holiday-buffer
2282                         fancy-diary-buffer diary-buffer calendar-buffer
2283                         other-calendars-buffer))
2284          (buffer-list nil)
2285          b)
2286     (while buffers
2287       (setq b (car buffers))
2288       (setq b (cond ((stringp b) (get-buffer b))
2289                     ((bufferp b) b)
2290                     (t nil)))
2291       (if b (setq buffer-list (cons b buffer-list)))
2292       (setq buffers (cdr buffers)))
2293     buffer-list))
2294
2295 (defun exit-calendar ()
2296   "Get out of the calendar window and hide it and related buffers."
2297   (interactive)
2298   (let* ((diary-buffer (get-file-buffer diary-file)))
2299     (if (or (not diary-buffer)
2300             (not (buffer-modified-p diary-buffer))
2301             (yes-or-no-p
2302              "Diary modified; do you really want to exit the calendar? "))
2303       ;; Need to do this multiple times because one time can replace some
2304       ;; calendar-related buffers with other calendar-related buffers
2305       (mapcar (lambda (x)
2306                 (mapcar 'calendar-hide-window (calendar-window-list)))
2307               (calendar-window-list)))))
2308
2309 (defun calendar-hide-window (window)
2310   "Hide WINDOW if it is calendar-related."
2311   (let ((buffer (if (window-live-p window) (window-buffer window))))
2312     (if (memq buffer (calendar-buffer-list))
2313         (cond
2314          ((and (display-multi-frame-p)
2315                (eq 'icon (cdr (assoc 'visibility
2316                                      (frame-parameters
2317                                       (window-frame window))))))
2318           nil)
2319          ((and (display-multi-frame-p) (window-dedicated-p window))
2320           (if calendar-remove-frame-by-deleting
2321               (delete-frame (window-frame window))
2322               (iconify-frame (window-frame window))))
2323          ((not (and (select-window window) (one-window-p window)))
2324           (delete-window window))
2325          (t (set-buffer buffer)
2326             (bury-buffer))))))
2327
2328 (defun calendar-current-date ()
2329   "Return the current date in a list (month day year)."
2330   (let ((now (decode-time)))
2331     (list (nth 4 now) (nth 3 now) (nth 5 now))))
2332
2333 (defun calendar-cursor-to-date (&optional error)
2334   "Return a list (month day year) of current cursor position.
2335 If cursor is not on a specific date, signals an error if optional parameter
2336 ERROR is t, otherwise just returns nil."
2337   (let* ((segment (/ (current-column) 25))
2338          (month (% (+ displayed-month segment -1) 12))
2339          (month (if (= 0 month) 12 month))
2340          (year
2341           (cond
2342            ((and (=  12 month) (= segment 0)) (1- displayed-year))
2343            ((and (=   1 month) (= segment 2)) (1+ displayed-year))
2344            (t displayed-year))))
2345     (if (and (looking-at "[ 0-9]?[0-9][^0-9]")
2346              (< 2 (count-lines (point-min) (point))))
2347         (save-excursion
2348           (if (not (looking-at " "))
2349                    (re-search-backward "[^0-9]"))
2350           (list month
2351                 (string-to-int (buffer-substring (1+ (point)) (+ 4 (point))))
2352                 year))
2353       (if (looking-at "\\*")
2354           (save-excursion
2355             (re-search-backward "[^*]")
2356             (if (looking-at ".\\*\\*")
2357                 (list month calendar-starred-day year)
2358               (if error (error "Not on a date!"))))
2359         (if error (error "Not on a date!"))))))
2360
2361 ;; The following version of calendar-gregorian-from-absolute is preferred for
2362 ;; reasons of clarity, BUT it's much slower than the version that follows it.
2363
2364 ;;(defun calendar-gregorian-from-absolute (date)
2365 ;;  "Compute the list (month day year) corresponding to the absolute DATE.
2366 ;;The absolute date is the number of days elapsed since the (imaginary)
2367 ;;Gregorian date Sunday, December 31, 1 BC."
2368 ;;  (let* ((approx (/ date 366));; Approximation from below.
2369 ;;         (year                ;; Search forward from the approximation.
2370 ;;          (+ approx
2371 ;;             (calendar-sum y approx
2372 ;;                 (>= date (calendar-absolute-from-gregorian (list 1 1 (1+ y))))
2373 ;;                  1)))
2374 ;;         (month         ;; Search forward from January.
2375 ;;          (1+ (calendar-sum m 1
2376 ;;                   (> date
2377 ;;                      (calendar-absolute-from-gregorian
2378 ;;                       (list m (calendar-last-day-of-month m year) year)))
2379 ;;                   1)))
2380 ;;         (day           ;; Calculate the day by subtraction.
2381 ;;          (- date
2382 ;;             (1- (calendar-absolute-from-gregorian (list month 1 year))))))
2383 ;;    (list month day year)))
2384
2385 (defun calendar-gregorian-from-absolute (date)
2386   "Compute the list (month day year) corresponding to the absolute DATE.
2387 The absolute date is the number of days elapsed since the (imaginary)
2388 Gregorian date Sunday, December 31, 1 BC."
2389 ;; See the footnote on page 384 of ``Calendrical Calculations, Part II:
2390 ;; Three Historical Calendars'' by E. M. Reingold,  N. Dershowitz, and S. M.
2391 ;; Clamen, Software--Practice and Experience, Volume 23, Number 4
2392 ;; (April, 1993), pages 383-404 for an explanation.
2393   (let* ((d0 (1- date))
2394          (n400 (/ d0 146097))
2395          (d1 (% d0 146097))
2396          (n100 (/ d1 36524))
2397          (d2 (% d1 36524))
2398          (n4 (/ d2 1461))
2399          (d3 (% d2 1461))
2400          (n1 (/ d3 365))
2401          (day (1+ (% d3 365)))
2402          (year (+ (* 400 n400) (* 100 n100) (* n4 4) n1)))
2403     (if (or (= n100 4) (= n1 4))
2404         (list 12 31 year)
2405       (let ((year (1+ year))
2406             (month 1))
2407         (while (let ((mdays (calendar-last-day-of-month month year)))
2408                  (and (< mdays day)
2409                       (setq day (- day mdays))))
2410           (setq month (1+ month)))
2411         (list month day year)))))
2412
2413 (defun calendar-other-month (month year)
2414   "Display a three-month calendar centered around MONTH and YEAR."
2415   (interactive (calendar-read-date 'noday))
2416   (if (and (= month displayed-month)
2417            (= year displayed-year))
2418       nil
2419     (let ((old-date (calendar-cursor-to-date))
2420           (today (calendar-current-date)))
2421       (generate-calendar-window month year)
2422       (calendar-cursor-to-visible-date
2423        (cond
2424         ((calendar-date-is-visible-p old-date) old-date)
2425         ((calendar-date-is-visible-p today) today)
2426         (t (list month 1 year)))))))
2427
2428 (defun calendar-set-mark (arg)
2429   "Mark the date under the cursor, or jump to marked date.
2430 With no prefix argument, push current date onto marked date ring.
2431 With argument, jump to mark, pop it, and put point at end of ring."
2432   (interactive "P")
2433   (let ((date (calendar-cursor-to-date t)))
2434     (if (null arg)
2435         (progn
2436           (setq calendar-mark-ring (cons date calendar-mark-ring))
2437           ;; Since the top of the mark ring is the marked date in the
2438           ;; calendar, the mark ring in the calendar is one longer than
2439           ;; in other buffers to get the same effect.
2440           (if (> (length calendar-mark-ring) (1+ mark-ring-max))
2441               (setcdr (nthcdr mark-ring-max calendar-mark-ring) nil))
2442           (message "Mark set"))
2443       (if (null calendar-mark-ring)
2444           (error "No mark set in this buffer")
2445         (calendar-goto-date (car calendar-mark-ring))
2446         (setq calendar-mark-ring
2447               (cdr (nconc calendar-mark-ring (list date))))))))
2448
2449 (defun calendar-exchange-point-and-mark ()
2450   "Exchange the current cursor position with the marked date."
2451   (interactive)
2452   (let ((mark (car calendar-mark-ring))
2453         (date (calendar-cursor-to-date t)))
2454     (if (null mark)
2455         (error "No mark set in this buffer")
2456       (setq calendar-mark-ring (cons date (cdr calendar-mark-ring)))
2457       (calendar-goto-date mark))))
2458
2459 (defun calendar-count-days-region ()
2460   "Count the number of days (inclusive) between point and the mark."
2461   (interactive)
2462   (let* ((days (- (calendar-absolute-from-gregorian
2463                    (calendar-cursor-to-date t))
2464                   (calendar-absolute-from-gregorian
2465                    (or (car calendar-mark-ring)
2466                        (error "No mark set in this buffer")))))
2467          (days (1+ (if (> days 0) days (- days)))))
2468     (message "Region has %d day%s (inclusive)"
2469              days (if (> days 1) "s" ""))))
2470
2471 (defun calendar-not-implemented ()
2472   "Not implemented."
2473   (interactive)
2474   (error "%s not available in the calendar"
2475          (global-key-binding (this-command-keys))))
2476
2477 (defun calendar-read (prompt acceptable &optional initial-contents)
2478   "Return an object read from the minibuffer.
2479 Prompt with the string PROMPT and use the function ACCEPTABLE to decide if
2480 entered item is acceptable.  If non-nil, optional third arg INITIAL-CONTENTS
2481 is a string to insert in the minibuffer before reading."
2482   (let ((value (read-minibuffer prompt initial-contents)))
2483     (while (not (funcall acceptable value))
2484       (setq value (read-minibuffer prompt initial-contents)))
2485     value))
2486
2487 (defun calendar-read-date (&optional noday)
2488   "Prompt for Gregorian date.  Return a list (month day year).
2489 If optional NODAY is t, does not ask for day, but just returns
2490 \(month nil year); if NODAY is any other non-nil value the value returned is
2491 \(month year)"
2492   (let* ((year (calendar-read
2493                 "Year (>0): "
2494                 (lambda (x) (> x 0))
2495                 (int-to-string (extract-calendar-year
2496                                 (calendar-current-date)))))
2497          (month-array calendar-month-name-array)
2498          (completion-ignore-case t)
2499          (month (cdr (assoc-ignore-case
2500                        (completing-read
2501                         "Month name: "
2502                         (mapcar 'list (append month-array nil))
2503                         nil t)
2504                       (calendar-make-alist month-array 1))))
2505          (last (calendar-last-day-of-month month year)))
2506     (if noday
2507         (if (eq noday t)
2508             (list month nil year)
2509           (list month year))
2510       (list month
2511             (calendar-read (format "Day (1-%d): " last)
2512                            (lambda (x) (and (< 0 x) (<= x last))))
2513             year))))
2514
2515 (defun calendar-interval (mon1 yr1 mon2 yr2)
2516   "The number of months difference between MON1, YR1 and MON2, YR2."
2517   (+ (* 12 (- yr2 yr1))
2518      (- mon2 mon1)))
2519
2520 (defvar calendar-abbrev-length 3
2521   "*Length of abbreviations to be used for day and month names.
2522 See also `calendar-day-abbrev-array' and `calendar-month-abbrev-array'.")
2523
2524 (defvar calendar-day-name-array
2525   ["Sunday" "Monday" "Tuesday" "Wednesday" "Thursday" "Friday" "Saturday"]
2526   "*Array of capitalized strings giving, in order, the day names.
2527 The first two characters of each string will be used to head the
2528 day columns in the calendar.  See also the variable
2529 `calendar-day-abbrev-array'.")
2530
2531 (defvar calendar-day-abbrev-array
2532   [nil nil nil nil nil nil nil]
2533   "*Array of capitalized strings giving the abbreviated day names.
2534 The order should be the same as that of the full names specified
2535 in `calendar-day-name-array'.  These abbreviations may be used
2536 instead of the full names in the diary file.  Do not include a
2537 trailing `.' in the strings specified in this variable, though
2538 you may use such in the diary file.  If any element of this array
2539 is nil, then the abbreviation will be constructed as the first
2540 `calendar-abbrev-length' characters of the corresponding full name.")
2541
2542 (defvar calendar-month-name-array
2543   ["January" "February" "March"     "April"   "May"      "June"
2544    "July"    "August"   "September" "October" "November" "December"]
2545   "*Array of capitalized strings giving, in order, the month names.
2546 See also the variable `calendar-month-abbrev-array'.")
2547
2548 (defvar calendar-month-abbrev-array
2549   [nil nil nil nil nil nil nil nil nil nil nil nil]
2550  "*Array of capitalized strings giving the abbreviated month names.
2551 The order should be the same as that of the full names specified
2552 in `calendar-month-name-array'.  These abbreviations are used in
2553 the calendar menu entries, and can also be used in the diary
2554 file.  Do not include a trailing `.' in the strings specified in
2555 this variable, though you may use such in the diary file.  If any
2556 element of this array is nil, then the abbreviation will be
2557 constructed as the first `calendar-abbrev-length' characters of the
2558 corresponding full name.")
2559
2560 (defun calendar-abbrev-construct (abbrev full &optional period)
2561   "Internal calendar function to return a complete abbreviation array.
2562 ABBREV is an array of abbreviations, FULL the corresponding array
2563 of full names.  The return value is the ABBREV array, with any nil
2564 elements replaced by the first three characters taken from the
2565 corresponding element of FULL.  If optional argument PERIOD is non-nil,
2566 each element returned has a final `.' character."
2567   (let (elem array)
2568     (dotimes (i (length full))
2569       (setq elem (or (aref abbrev i)
2570                      (substring (aref full i) 0 calendar-abbrev-length))
2571             elem (format "%s%s" elem (if period "." ""))
2572             array (append array (list elem))))
2573     (vconcat array)))
2574
2575 (defvar calendar-font-lock-keywords
2576   `((,(concat (regexp-opt (mapcar 'identity calendar-month-name-array) t)
2577               " -?[0-9]+")
2578      . font-lock-function-name-face) ; month and year
2579     (,(regexp-opt
2580        (list (substring (aref calendar-day-name-array 6) 0 2)
2581              (substring (aref calendar-day-name-array 0) 0 2)))
2582      ;; Saturdays and Sundays are hilited differently.
2583      . font-lock-comment-face)
2584     ;; First two chars of each day are used in the calendar.
2585     (,(regexp-opt (mapcar (lambda (x) (substring x 0 2)) calendar-day-name-array))
2586      . font-lock-reference-face))
2587   "Default keywords to highlight in Calendar mode.")
2588
2589 (defun calendar-day-name (date &optional abbrev absolute)
2590   "Return a string with the name of the day of the week of DATE.
2591 DATE should be a list in the format (MONTH DAY YEAR), unless the
2592 optional argument ABSOLUTE is non-nil, in which case DATE should
2593 be an integer in the range 0 to 6 corresponding to the day of the
2594 week.  Day names are taken from the variable `calendar-day-name-array',
2595 unless the optional argument ABBREV is non-nil, in which case
2596 the variable `calendar-day-abbrev-array' is used."
2597   (aref (if abbrev
2598             (calendar-abbrev-construct calendar-day-abbrev-array
2599                                        calendar-day-name-array)
2600           calendar-day-name-array)
2601         (if absolute date (calendar-day-of-week date))))
2602
2603 (defun calendar-make-alist (sequence &optional start-index filter abbrevs)
2604   "Make an assoc list corresponding to SEQUENCE.
2605 Each element of sequence will be associated with an integer, starting
2606 from 1, or from START-INDEX if that is non-nil.  If a sequence ABBREVS
2607 is supplied, the function `calendar-abbrev-construct' is used to
2608 construct abbreviations corresponding to the elements in SEQUENCE.
2609 Each abbreviation is entered into the alist with the same
2610 association index as the full name it represents.
2611 If FILTER is provided, apply it to each key in the alist."
2612   (let ((index 0)
2613         (offset (or start-index 1))
2614         (aseq (if abbrevs (calendar-abbrev-construct abbrevs sequence)))
2615         (aseqp (if abbrevs (calendar-abbrev-construct abbrevs sequence
2616                                                       'period)))
2617         alist elem)
2618     (dotimes (i (1- (length sequence)) (reverse alist))
2619       (setq index (+ i offset)
2620             elem (elt sequence i)
2621             alist
2622             (cons (cons (if filter (funcall filter elem) elem) index) alist))
2623       (if aseq
2624           (setq elem (elt aseq i)
2625                 alist (cons (cons (if filter (funcall filter elem) elem)
2626                                   index) alist)))
2627       (if aseqp
2628           (setq elem (elt aseqp i)
2629                 alist (cons (cons (if filter (funcall filter elem) elem)
2630                                   index) alist))))))
2631
2632 (defun calendar-month-name (month &optional abbrev)
2633   "Return a string with the name of month number MONTH.
2634 Months are numbered from one.  Month names are taken from the
2635 variable `calendar-month-name-array', unless the optional
2636 argument ABBREV is non-nil, in which case
2637 `calendar-month-abbrev-array' is used."
2638   (aref (if abbrev
2639             (calendar-abbrev-construct calendar-month-abbrev-array
2640                                        calendar-month-name-array)
2641           calendar-month-name-array)
2642         (1- month)))
2643
2644 (defun calendar-day-of-week (date)
2645   "Return the day-of-the-week index of DATE, 0 for Sunday, 1 for Monday, etc."
2646   (% (calendar-absolute-from-gregorian date) 7))
2647
2648 (defun calendar-unmark ()
2649   "Delete all diary/holiday marks/highlighting from the calendar."
2650   (interactive)
2651   (setq mark-holidays-in-calendar nil)
2652   (setq mark-diary-entries-in-calendar nil)
2653   (redraw-calendar))
2654
2655 (defun calendar-date-is-visible-p (date)
2656   "Return t if DATE is legal and is visible in the calendar window."
2657   (let ((gap (calendar-interval
2658               displayed-month displayed-year
2659               (extract-calendar-month date) (extract-calendar-year date))))
2660     (and (calendar-date-is-legal-p date) (> 2 gap) (< -2 gap))))
2661
2662 (defun calendar-date-is-legal-p (date)
2663   "Return t if DATE is a legal date."
2664   (let ((month (extract-calendar-month date))
2665         (day (extract-calendar-day date))
2666         (year (extract-calendar-year date)))
2667     (and (<= 1 month) (<= month 12)
2668          (<= 1 day) (<= day (calendar-last-day-of-month month year))
2669          (<= 1 year))))
2670
2671 (defun calendar-date-equal (date1 date2)
2672   "Return t if the DATE1 and DATE2 are the same."
2673   (and
2674    (= (extract-calendar-month date1) (extract-calendar-month date2))
2675    (= (extract-calendar-day date1) (extract-calendar-day date2))
2676    (= (extract-calendar-year date1) (extract-calendar-year date2))))
2677
2678 (defun mark-visible-calendar-date (date &optional mark)
2679   "Mark DATE in the calendar window with MARK.
2680 MARK is a single-character string, a list of face attributes/values, or a face.
2681 MARK defaults to `diary-entry-marker'."
2682   (if (calendar-date-is-legal-p date)
2683       (save-excursion
2684         (set-buffer calendar-buffer)
2685         (calendar-cursor-to-visible-date date)
2686         (let ((mark (or (and (stringp mark) (= (length mark) 1) mark) ; single-char
2687                         (and (listp mark) (> (length mark) 0) mark) ; attr list
2688                         (and (facep mark) mark) ; face-name
2689                         diary-entry-marker)))
2690           (if (facep mark)
2691               (progn ; face or an attr-list that contained a face
2692                 (overlay-put
2693                  (make-overlay (1- (point)) (1+ (point))) 'face mark))
2694             (if (and (stringp mark)
2695                      (= (length mark) 1)) ; single-char
2696                 (let ((buffer-read-only nil))
2697                   (forward-char 1)
2698                   (delete-char 1)
2699                   (insert mark)
2700                   (forward-char -2))
2701               (progn ; attr list
2702                 (setq temp-face
2703                       (make-symbol (apply 'concat "temp-face-"
2704                                           (mapcar '(lambda (sym)
2705                                                      (cond ((symbolp sym) (symbol-name sym))
2706                                                            ((numberp sym) (int-to-string sym))
2707                                                            (t sym))) mark))))
2708                 (make-face temp-face)
2709                 ;; Remove :face info from the mark, copy the face info into temp-face
2710                 (setq faceinfo mark)
2711                 (while (setq faceinfo (memq :face faceinfo))
2712                   (copy-face (read (nth 1 faceinfo)) temp-face)
2713                   (setcar faceinfo nil)
2714                   (setcar (cdr faceinfo) nil))
2715                 (setq mark (delq nil mark))
2716                 ;; Apply the font aspects
2717                 (apply 'set-face-attribute temp-face nil mark)
2718                 (overlay-put
2719                  (make-overlay (1- (point)) (1+ (point))) 'face temp-face))))))))
2720
2721 (defun calendar-star-date ()
2722   "Replace the date under the cursor in the calendar window with asterisks.
2723 This function can be used with the `today-visible-calendar-hook' run after the
2724 calendar window has been prepared."
2725   (let ((inhibit-read-only t))
2726     (make-local-variable 'calendar-starred-day)
2727     (forward-char 1)
2728     (setq calendar-starred-day
2729           (string-to-int
2730            (buffer-substring (point) (- (point) 2))))
2731     (delete-char -2)
2732     (insert "**")
2733     (backward-char 1)
2734     (set-buffer-modified-p nil)))
2735
2736 (defun calendar-mark-today ()
2737   "Mark the date under the cursor in the calendar window.
2738 The date is marked with `calendar-today-marker'.  This function can be used with
2739 the `today-visible-calendar-hook' run after the calendar window has been
2740 prepared."
2741   (mark-visible-calendar-date
2742    (calendar-cursor-to-date)
2743    calendar-today-marker))
2744
2745 (defun calendar-date-compare (date1 date2)
2746   "Return t if DATE1 is before DATE2, nil otherwise.
2747 The actual dates are in the car of DATE1 and DATE2."
2748   (< (calendar-absolute-from-gregorian (car date1))
2749      (calendar-absolute-from-gregorian (car date2))))
2750
2751 (defun calendar-date-string (date &optional abbreviate nodayname)
2752   "A string form of DATE, driven by the variable `calendar-date-display-form'.
2753 An optional parameter ABBREVIATE, when non-nil, causes the month
2754 and day names to be abbreviated as specified by
2755 `calendar-month-abbrev-array' and `calendar-day-abbrev-array',
2756 respectively.  An optional parameter NODAYNAME, when t, omits the
2757 name of the day of the week."
2758   (let* ((dayname
2759           (unless nodayname
2760             (calendar-day-name date abbreviate)))
2761          (month (extract-calendar-month date))
2762          (monthname (calendar-month-name month abbreviate))
2763          (day (int-to-string (extract-calendar-day date)))
2764          (month (int-to-string month))
2765          (year (int-to-string (extract-calendar-year date))))
2766     (mapconcat 'eval calendar-date-display-form "")))
2767
2768 (defun calendar-dayname-on-or-before (dayname date)
2769   "Return the absolute date of the DAYNAME on or before absolute DATE.
2770 DAYNAME=0 means Sunday, DAYNAME=1 means Monday, and so on.
2771
2772 Note: Applying this function to d+6 gives us the DAYNAME on or after an
2773 absolute day d.  Similarly, applying it to d+3 gives the DAYNAME nearest to
2774 absolute date d, applying it to d-1 gives the DAYNAME previous to absolute
2775 date d, and applying it to d+7 gives the DAYNAME following absolute date d."
2776   (- date (% (- date dayname) 7)))
2777
2778 (defun calendar-nth-named-absday (n dayname month year &optional day)
2779   "The absolute date of Nth DAYNAME in MONTH, YEAR before/after optional DAY.
2780 A DAYNAME of 0 means Sunday, 1 means Monday, and so on.  If N<0,
2781 return the Nth DAYNAME before MONTH DAY, YEAR (inclusive).
2782 If N>0, return the Nth DAYNAME after MONTH DAY, YEAR (inclusive).
2783
2784 If DAY is omitted, it defaults to 1 if N>0, and MONTH's last day otherwise."
2785   (if (> n 0)
2786       (+ (* 7 (1- n))
2787          (calendar-dayname-on-or-before
2788           dayname
2789           (+ 6 (calendar-absolute-from-gregorian
2790                 (list month (or day 1) year)))))
2791     (+ (* 7 (1+ n))
2792        (calendar-dayname-on-or-before
2793         dayname
2794         (calendar-absolute-from-gregorian
2795          (list month
2796                (or day (calendar-last-day-of-month month year))
2797                year))))))
2798
2799 (defun calendar-nth-named-day (n dayname month year &optional day)
2800   "The date of Nth DAYNAME in MONTH, YEAR before/after optional DAY.
2801 A DAYNAME of 0 means Sunday, 1 means Monday, and so on.  If N<0,
2802 return the Nth DAYNAME before MONTH DAY, YEAR (inclusive).
2803 If N>0, return the Nth DAYNAME after MONTH DAY, YEAR (inclusive).
2804
2805 If DAY is omitted, it defaults to 1 if N>0, and MONTH's last day otherwise."
2806   (calendar-gregorian-from-absolute
2807    (calendar-nth-named-absday n dayname month year day)))
2808
2809 (defun calendar-day-of-year-string (&optional date)
2810   "String of day number of year of Gregorian DATE.
2811 Defaults to today's date if DATE is not given."
2812   (let* ((d (or date (calendar-current-date)))
2813          (year (extract-calendar-year d))
2814          (day (calendar-day-number d))
2815          (days-remaining (- (calendar-day-number (list 12 31 year)) day)))
2816     (format "Day %d of %d; %d day%s remaining in the year"
2817             day year days-remaining (if (= days-remaining 1) "" "s"))))
2818
2819 (defun calendar-print-other-dates ()
2820   "Show dates on other calendars for date under the cursor."
2821   (interactive)
2822   (let* ((date (calendar-cursor-to-date t)))
2823     (save-excursion
2824       (set-buffer (get-buffer-create other-calendars-buffer))
2825       (setq buffer-read-only nil)
2826       (calendar-set-mode-line
2827        (concat (calendar-date-string date) " (Gregorian)"))
2828       (erase-buffer)
2829       (insert
2830        (mapconcat 'identity
2831                   (list (calendar-day-of-year-string date)
2832                         (format "ISO date: %s" (calendar-iso-date-string date))
2833                         (format "Julian date: %s"
2834                                 (calendar-julian-date-string date))
2835                         (format
2836                          "Astronomical (Julian) day number (at noon UTC): %s.0"
2837                          (calendar-astro-date-string date))
2838                         (format "Fixed (RD) date: %s"
2839                                 (calendar-absolute-from-gregorian date))
2840                         (format "Hebrew date (before sunset): %s"
2841                                 (calendar-hebrew-date-string date))
2842                         (format "Persian date: %s"
2843                                 (calendar-persian-date-string date))
2844                         (let ((i (calendar-islamic-date-string date)))
2845                           (if (not (string-equal i ""))
2846                               (format "Islamic date (before sunset): %s" i)))
2847                         (format "Chinese date: %s"
2848                                 (calendar-chinese-date-string date))
2849                         (let ((c (calendar-coptic-date-string date)))
2850                           (if (not (string-equal c ""))
2851                               (format "Coptic date: %s" c)))
2852                         (let ((e (calendar-ethiopic-date-string date)))
2853                           (if (not (string-equal e ""))
2854                               (format "Ethiopic date: %s" e)))
2855                         (let ((f (calendar-french-date-string date)))
2856                           (if (not (string-equal f ""))
2857                               (format "French Revolutionary date: %s" f)))
2858                         (format "Mayan date: %s"
2859                                 (calendar-mayan-date-string date)))
2860                   "\n"))
2861       (goto-char (point-min))
2862       (set-buffer-modified-p nil)
2863       (setq buffer-read-only t)
2864       (display-buffer other-calendars-buffer))))
2865
2866 (defun calendar-print-day-of-year ()
2867   "Show day number in year/days remaining in year for date under the cursor."
2868   (interactive)
2869   (message (calendar-day-of-year-string (calendar-cursor-to-date t))))
2870
2871 (defun calendar-set-mode-line (str)
2872   "Set mode line to STR, centered, surrounded by dashes."
2873   (setq mode-line-format
2874         (calendar-string-spread (list str) ?- (frame-width))))
2875
2876 (defun calendar-mod (m n)
2877   "Non-negative remainder of M/N with N instead of 0."
2878   (1+ (mod (1- m) n)))
2879
2880 (run-hooks 'calendar-load-hook)
2881
2882 (provide 'calendar)
2883
2884 ;;; Local variables:
2885 ;;; byte-compile-dynamic: t
2886 ;;; End:
2887
2888 ;;; calendar.el ends here