1Date::Calendar::ProfileUss(e3r)Contributed Perl DocumentDaattieo:n:Calendar::Profiles(3)
2
3
4

NAME

6       Date::Calendar::Profiles - Some sample profiles for Date::Calendar and
7       Date::Calendar::Year
8

SYNOPSIS

10         use Date::Calendar::Profiles qw( $Profiles );
11         use Date::Calendar;
12
13         $cal_US_AK = Date::Calendar->new( $Profiles->{'US-AK'} [,LANG[,WEEKEND]] );
14         $cal_DE_BY = Date::Calendar->new( $Profiles->{'DE-BY'} [,LANG[,WEEKEND]] );
15
16        or
17
18         use Date::Calendar::Profiles qw( $Profiles );
19         use Date::Calendar::Year;
20
21         $year_2000_US_FL = Date::Calendar::Year->new( 2000, $Profiles->{'US-FL'} [,LANG[,WEEKEND]] );
22         $year_2001_DE_NW = Date::Calendar::Year->new( 2001, $Profiles->{'DE-NW'} [,LANG[,WEEKEND]] );
23
24        and also
25
26         use Date::Calendar::Profiles
27         qw(
28             &Previous_Friday
29             &Next_Monday
30             &Next_Monday_or_Tuesday
31             &Nearest_Workday
32             &Sunday_to_Monday
33             &Advent1
34             &Advent2
35             &Advent3
36             &Advent4
37             &Advent
38         );
39

PREFACE

41       This module provides some sample profiles (i.e., holiday schemes) for
42       use with the Date::Calendar(3) and Date::Calendar::Year(3) module.
43
44       You are not required to use these, you can always roll your own (this
45       is very easy). See the section "HOW TO ROLL YOUR OWN" below for more
46       instructions on how to do this, and take the profiles from this module
47       as examples.
48
49       I intend not to make any fixes to any of the calendar profiles in this
50       module anymore unless there are VERY compelling reasons to do so. These
51       profiles are merely meant as examples.
52
53       The suggested way of using these profiles is to copy them to your own
54       code and then to modify them as needed. Otherwise many people could be
55       negatively affected if I made any changes to a profile someone has been
56       using for years.
57
58       Any improvements are therefore left as an exercise to the inclined
59       reader.
60

DESCRIPTION

62       The method "init()" in module Date::Calendar::Year(3) is responsible
63       for parsing the calendar schemes contained here in the
64       Date::Calendar::Profiles module.
65
66       This method offers a "mini-language" which allows to specify common
67       date formulas, like for instance a simple fixed date (in various
68       different formats, e.g. american or european), or things like "the
69       second Sunday of May" (Mother's Day), or "Easter Sunday minus 46 days"
70       (Ash Wednesday), to cite just a few.
71
72       See the section "DATE FORMULA SYNTAX" below for more details.
73
74       There are some more complicated formulas, however, which cannot be
75       expressed in such simple terms.
76
77       The rule that if a holiday falls on a weekend, it will be substituted
78       by either the adjacent Friday or Monday (whichever lies closer), is an
79       example of this.
80
81       In order to be able to deal with such formulas, and in order to be as
82       flexible as possible, the "init()" method offers the possibility of
83       using callback functions to deal with such dates and formulas.
84
85       See the section "CALLBACK INTERFACE" below for more details on this
86       topic.
87
88       In order to assist you with more common cases of odd formulas, the
89       module Date::Calendar::Profiles exports the following utility
90       subroutines (which are meant to be used as "filters" in callback
91       functions of your own):
92
93       • "($year,$month,$day[,ANYTHING]) =
94         Previous_Friday($year,$month,$day[,ANYTHING]);"
95
96         If the given date falls on a Saturday or Sunday, this function
97         changes the date to the adjacent Friday before that, and returns this
98         new date.
99
100         Otherwise the given date is returned unchanged.
101
102         The rest of the input parameters, if any, are simply copied to the
103         output.
104
105       • "($year,$month,$day[,ANYTHING]) =
106         Next_Monday($year,$month,$day[,ANYTHING]);"
107
108         If the given date falls on a Saturday or Sunday, this function
109         changes the date to the adjacent Monday after that, and returns this
110         new date.
111
112         Otherwise the given date is returned unchanged.
113
114         The rest of the input parameters, if any, are simply copied to the
115         output.
116
117       • "($year,$month,$day[,ANYTHING]) =
118         Next_Monday_or_Tuesday($year,$month,$day[,ANYTHING]);"
119
120         If the given date falls on a Saturday, the date of the next Monday
121         (after that weekend) is returned.
122
123         If the given date falls on a Sunday, the date of the next Tuesday
124         (after that weekend) is returned.
125
126         If the given date falls on a Monday, the date of the next Tuesday
127         (the day after the Monday) is returned.
128
129         Otherwise the given date is returned unchanged.
130
131         The rest of the input parameters, if any, are simply copied to the
132         output.
133
134         This function is used for the second of two adjacent holidays, where
135         the first holiday obeys the "Next Monday" rule (see the description
136         of the function immediately above).
137
138         Examples of this are Christmas and Boxing Day, among others.
139
140         When the first holiday falls on Friday, the second one falls on
141         Saturday and is substituted by Monday.
142
143         When the first holiday falls on a Saturday, the second one falls on
144         Sunday, so the first holiday is substituted by Monday and the second
145         one by Tuesday.
146
147         When the first holiday falls on a Sunday, the second one falls on a
148         Monday. Therefore the first holiday is substituted by Monday, and
149         consequently the second holiday must be substituted by Tuesday.
150
151         Or, in other terms:
152
153             Fri Sat => Fri Mon
154             Sat Sun => Mon Tue
155             Sun Mon => Mon Tue
156
157         Note that there is no filter subroutine yet for the second of two
158         adjacent holidays when the first holiday obeys the "Nearest Workday"
159         rule (see the function described immediately below), i.e.,
160
161             Fri Sat => Fri Mon
162             Sat Sun => Fri Mon
163             Sun Mon => Mon Tue
164
165         This is left as an excercise to the inclined reader. ":-)"
166
167       • "($year,$month,$day[,ANYTHING]) =
168         Nearest_Workday($year,$month,$day[,ANYTHING]);"
169
170         If the given date falls on a Saturday, this function returns the date
171         of the Friday on the day before.
172
173         If the given date falls on a Sunday, this function returns the date
174         of the Monday on the day after.
175
176         Otherwise the given date is returned unchanged.
177
178         The rest of the input parameters, if any, are simply copied to the
179         output.
180
181       • "($year,$month,$day[,ANYTHING]) =
182         Sunday_to_Monday($year,$month,$day[,ANYTHING]);"
183
184         If the given date falls on a Sunday, this function returns the date
185         of the Monday on the day after.
186
187         Otherwise the given date is returned unchanged.
188
189         The rest of the input parameters, if any, are simply copied to the
190         output.
191
192       The typical use of these filter subroutines is in a "return" statement
193       at the end of callback functions of your own, when you already have
194       calculated the holiday in question and only need to adjust it according
195       to the rule implemented by the filter subroutine in question.
196
197       See also the implementation of the Date::Calendar::Profiles module for
198       examples of how to use these functions.
199

DATE FORMULA SYNTAX

201        -  Fixed dates:
202
203           "Christmas"  =>  "24.12",   # European format (day, month)
204           "Christmas"  =>  "24.12.",
205
206           "Christmas"  =>  "24Dec",
207           "Christmas"  =>  "24.Dec",
208           "Christmas"  =>  "24Dec.",
209           "Christmas"  =>  "24.Dec.",
210
211           "Christmas"  =>  "24-12",
212           "Christmas"  =>  "24-12-",
213
214           "Christmas"  =>  "24-Dec",
215           "Christmas"  =>  "24-Dec-",
216
217           "Christmas"  =>  "12/25",   # American format (month, day)
218           "Christmas"  =>  "Dec25",
219           "Christmas"  =>  "Dec/25",
220
221        -  Dates relative to Easter Sunday:
222
223           "Ladies' Carnival"  =>  "-52",
224           "Carnival Monday"   =>  "-48",
225           "Mardi Gras"        =>  "-47",
226           "Ash Wednesday"     =>  "-46",
227           "Palm Sunday"       =>   "-7",
228           "Maundy Thursday"   =>   "-3",
229           "Good Friday"       =>   "-2",
230           "Easter Sunday"     =>   "+0",
231           "Easter Monday"     =>   "+1",
232           "Ascension"         =>  "+39",
233           "Whitsunday"        =>  "+49",
234           "Whitmonday"        =>  "+50",
235           "Corpus Christi"    =>  "+60",
236
237        -  The 1st, 2nd, 3rd, 4th or last day of week:
238
239           "Thanksgiving"      =>  "4Thu11",
240           "Thanksgiving"      =>  "4/Thu/Nov",
241           "Columbus Day"      =>  "2/Mon/Oct",
242           "Columbus Day"      =>  "2/Mon/10",
243           "Columbus Day"      =>  "2/1/Oct",
244           "Columbus Day"      =>  "2/1/10",
245           "Memorial Day"      =>  "5/Mon/May", # LAST Monday of May
246
247        -  Half holidays, commemorative days:
248
249           "Christmas"         =>  ":24.12.", # only half a day off
250           "Valentine's Day"   =>  "#Feb/14", # not an official holiday
251

CALLBACK INTERFACE

253       The interface of the callback functions to use with the "init()" method
254       of the Date::Calendar::Year(3) module is very simple:
255
256       The callback function receives two arguments when called, first the
257       year number for which the holiday is to be calculated, and second the
258       name (the "label") of the holiday in question (which serves as key in
259       the hash of a holiday scheme).
260
261       This second parameter allows you to use the same callback function for
262       different holidays, which might be more practical (than separate
263       callback functions) if for instance you have a set of similar holidays
264       to calculate, like for instance the four Sundays before Christmas
265       ("Advent").
266
267       The callback function "Advent()" (exported by the
268       Date::Calendar::Profiles module) exemplifies this technique.
269
270       The callback function is expected to return a list
271       ""($year,$month,$day)"" with the exact date of the holiday (the year
272       number in the output must of course match the year number passed as
273       parameter).
274
275       A fatal error occurs if the returned list does not constitute a valid
276       date, in the requested year.
277
278       Optionally, the callback function may return a fourth value (after the
279       date) containing a string, which may be either "#" or ":".
280
281       The string "#" signifies that the date in question is a purely
282       commemorative date, i.e., that you don't get a day off from work on
283       that day.
284
285       The string ":" means that the date in question is a "half" holiday,
286       i.e., a day on which you get half a day off from work.
287
288       In case the holiday in question was not observed or did not exist in
289       the requested year, the callback function may also return an empty
290       list. This will cause the "init()" method to simply drop this holiday
291       for that year.
292
293       The module Date::Calendar::Profiles exports the sample callback
294       functions "Advent1()", "Advent2()", "Advent3()", "Advent4()" and
295       "Advent()", which might assist you in rolling your own profiles.
296

HOW TO ROLL YOUR OWN

298       Every calendar profile (holiday scheme) is a hash.
299
300       The name of the holiday (like "Christmas", for instance) serves as the
301       key in this hash and must therefore be unique (unless you want to
302       override a default which was set previously, but see below for more on
303       this).
304
305       The value for each key is either a string, which specifies a simple
306       date formula, or the reference of a callback function.
307
308       See the section "CALLBACK INTERFACE" above for a description of the
309       interface (in and out) of these callback functions.
310
311       See the section "DATE FORMULA SYNTAX" above and the description of the
312       "init()" method in Date::Calendar::Year(3) for the exact syntax of date
313       formula strings.
314
315       BEWARE that if keys are not unique in the source code, later entries
316       will overwrite previous ones! I.e.,
317
318           ...
319           "My special holiday" => "01-11",
320           "My special holiday" => "02-11",
321           ...
322
323       will NOT set two holidays of the same name, one on November first, the
324       other on November second, but only one, on November second!
325
326       Therefore, in order to use sets of defaults and to be able to override
327       some of them, you must FIRST include any hash containing the default
328       definitions, and THEN write down your own definitions (see also the
329       Date::Calendar::Profiles module for examples of this!), like this:
330
331           $defaults =
332           {
333               "Holiday #1" => "01-01",
334               "Holiday #2" => "02-02",
335               "Holiday #3" => "03-03"
336           };
337
338           $variant1 =
339           {
340               %$defaults,
341               "Holiday #2" => "09-02",
342               "Holiday #4" => "04-04"
343           };
344
345       This is because of the way hashes work in Perl.
346
347       Now let's suppose that you want to write a profile containing all your
348       relatives' and friends' birthdays or anniversaries.
349
350       Simply go ahead and list them in your program, in any order you like,
351       as follows (for example):
352
353         $Birthdays =
354         {
355             "Spouse 1971"             =>  "30.12.",
356             "Wedding Day 1992"        =>  "01.09.",
357             "Valentine's Day"         =>  "14.02.",
358             "Son Richard 1996"        =>  "11.05.",
359             "Daughter Irene 1994"     =>  "17.01.",
360             "Mom 1939"                =>  "19.08.",
361             "Dad 1937"                =>  "23.04.",
362             "Brother Timothy 1969"    =>  "24.04.",
363             "Sister Catherine 1973"   =>  "21.10.",
364             "Cousin Paul 1970"        =>  "16.10.",
365             "Aunt Marjorie 1944"      =>  "09.06.",
366             "Uncle George 1941"       =>  "02.08.",
367             "Friend Alexander 1968"   =>  "12.06.",
368         };
369
370       The year numbers after the names are not really necessary, but they
371       allow us to display the person's current age. If this year number is
372       omitted, we simply don't display the age.
373
374       Now in order to query this birthday database, we can use the following
375       little program:
376
377         #!perl -w
378
379         use strict;
380         no strict "vars";
381         use Date::Calc qw(:all);
382         use Date::Calendar;
383
384         $Birthdays =
385         {
386             ... # (see above)
387         };
388
389         @today = Today();
390         $calendar = Date::Calendar->new( $Birthdays );
391         $calendar->year( $today[0] );
392
393         foreach $key (@ARGV)
394         {
395             if (@list = $calendar->search( $key ))
396             {
397                 foreach $date (@list)
398                 {
399                     @labels = $calendar->labels( $date );
400                     $dow = shift(@labels);
401                     # More than one person might have birthday on the same date:
402                     $name = $key;
403                     foreach $person (@labels)
404                     {
405                         if (index(lc($person),lc($key)) >= 0)
406                         {
407                             $name = $person;
408                             last;
409                         }
410                     }
411                     $delta = Delta_Days(@today, $date->date());
412                     $age = '';
413                     if ($name =~ s!\s*(\d+)\s*$!!)
414                     {
415                         $age = $today[0] - $1;
416                         $age-- if ($delta > 0);
417                         $age = sprintf(" (%2d years old)", $age);
418                     }
419                     printf
420                     (
421                         "%-20.20s: %+5d days => %3.3s %2d-%3.3s-%4d%s\n",
422                         $name,
423                         $delta,
424                         $dow,
425                         $date->day(),
426                         Month_to_Text($date->month()),
427                         $date->year(),
428                         $age
429                     );
430                 }
431             }
432             else { print "No entry found in birthday list for '$key'!\n" }
433         }
434
435         __END__
436
437       Let us save this program as, say, "birthday.pl".
438
439       Then we can query this birthday database by providing search strings on
440       the command line, like this (note that this is a (case-insensitive)
441       substring search, NOT a regular expression match!):
442
443         > date
444         Wed Oct  3 18:05:45 CEST 2001
445
446         > perl birthday.pl wed spo
447         Wedding Day         :   -32 days => Sat  1-Sep-2001 ( 9 years old)
448         Spouse              :   +88 days => Sun 30-Dec-2001 (29 years old)
449
450         > perl birthday.pl son daug
451         Son Richard         :  -145 days => Fri 11-May-2001 ( 5 years old)
452         Daughter Irene      :  -259 days => Wed 17-Jan-2001 ( 7 years old)
453
454         > perl birthday.pl broth sist
455         Brother Timothy     :  -162 days => Tue 24-Apr-2001 (32 years old)
456         Sister Catherine    :   +18 days => Sun 21-Oct-2001 (27 years old)
457
458         > perl birthday.pl mom dad
459         Mom                 :   -45 days => Sun 19-Aug-2001 (62 years old)
460         Dad                 :  -163 days => Mon 23-Apr-2001 (64 years old)
461
462         > perl birthday.pl uncl aunt
463         Uncle George        :   -62 days => Thu  2-Aug-2001 (60 years old)
464         Aunt Marjorie       :  -116 days => Sat  9-Jun-2001 (57 years old)
465
466         > perl birthday.pl alex
467         Friend Alexander    :  -113 days => Tue 12-Jun-2001 (33 years old)
468
469       In order to get the whole list, we can supply a substring which is
470       contained in every name, which happens to be a blank (" "):
471
472         > perl birthday.pl ' '
473         Daughter Irene      :  -259 days => Wed 17-Jan-2001 ( 7 years old)
474         Valentine's Day     :  -231 days => Wed 14-Feb-2001
475         Dad                 :  -163 days => Mon 23-Apr-2001 (64 years old)
476         Brother Timothy     :  -162 days => Tue 24-Apr-2001 (32 years old)
477         Son Richard         :  -145 days => Fri 11-May-2001 ( 5 years old)
478         Aunt Marjorie       :  -116 days => Sat  9-Jun-2001 (57 years old)
479         Friend Alexander    :  -113 days => Tue 12-Jun-2001 (33 years old)
480         Uncle George        :   -62 days => Thu  2-Aug-2001 (60 years old)
481         Mom                 :   -45 days => Sun 19-Aug-2001 (62 years old)
482         Wedding Day         :   -32 days => Sat  1-Sep-2001 ( 9 years old)
483         Cousin Paul         :   +13 days => Tue 16-Oct-2001 (30 years old)
484         Sister Catherine    :   +18 days => Sun 21-Oct-2001 (27 years old)
485         Spouse              :   +88 days => Sun 30-Dec-2001 (29 years old)
486
487       By the way, a similar program is included in the "examples"
488       subdirectory of the Date::Calc distribution, called "anniversaries.pl".
489
490       See also the file "EXAMPLES.txt" in the distribution's main directory
491       for a short description of that little script.
492

SEE ALSO

494       Date::Calendar(3), Date::Calendar::Year(3), Date::Calc::Object(3),
495       Date::Calc(3), Date::Calc::Util(3).
496

LIMITATIONS

498       The calendar profiles included in this module usually do not take
499       historical irregularities into account (even though some do in order to
500       show how this can be done), they only provide means for calculating
501       regularly recurring events (the profiles should therefore not be relied
502       upon for historical faithfulness).
503

KNOWN BUGS

505       The australian calendar profiles are known to contain wrong dates.
506       This is due to the fact that Australia decrees its holidays
507       individually for each year, difficulting the calculation of the
508       holidays by way of a formula. An effort to compare (and to correct) the
509       current implementation with official documents (web pages) by the
510       Australian authorities is under way. This hasn't been finished yet
511       because it is very time-consuming.
512

VERSION

514       This man page documents "Date::Calendar::Profiles" version 6.4.
515

AUTHOR

517         Steffen Beyer
518         mailto:STBEY@cpan.org
519         http://www.engelschall.com/u/sb/download/
520
522       Copyright (c) 2000 - 2015 by Steffen Beyer. All rights reserved.
523

LICENSE

525       This package is free software; you can use, modify and redistribute it
526       under the same terms as Perl itself, i.e., at your option, under the
527       terms either of the "Artistic License" or the "GNU General Public
528       License".
529
530       The C library at the core of the module "Date::Calc::XS" can, at your
531       discretion, also be used, modified and redistributed under the terms of
532       the "GNU Library General Public License".
533
534       Please refer to the files "Artistic.txt", "GNU_GPL.txt" and
535       "GNU_LGPL.txt" in the "license" subdirectory of this distribution for
536       any details!
537

DISCLAIMER

539       This package is distributed in the hope that it will be useful, but
540       WITHOUT ANY WARRANTY; without even the implied warranty of
541       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
542
543       See the "GNU General Public License" for more details.
544
545
546
547perl v5.38.0                      2023-07-20       Date::Calendar::Profiles(3)
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