Copyright (c) 1995-1997 Sullivan Beck. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. For information on installing Date::Manip, see the INSTALL file included in the distribution. Please send questions or bug reports to me rather than posting them to a newsgroup since I may miss them there, but read the next paragraph before you automatically start firing off email to me! If you have questions about Date::Manip, refer to the Date::Manip man page included as pod documentation in the Manip.pm file. Don't know what I'm talking about? Read the perlpod man page. Alternately, an online version of the Date::Manip man page is included in my home page given below. PLEASE read the man page thoroughly before posting any questions about Date::Manip to a newsgroup or emailing me. If you've done this, I'll be glad to answer any questions not covered in the man page. Notes for version 5.20: Added ISO 8601 date formats. Added ParseDateString for speed. Changed week handling to meet ISO 8601 standards. Added %J and %K UnixDate formats. Added some speedups (more to come). Added more Parse formats: last day in mmm in YY "last day of October" dofw "Friday" (Friday of current week) Nth "12th", "1st" (day of current month) Version 5.20 has some incompatibilities with previous versions: Some old formats were removed since they conflicted with ISO 8601 formats. MM-DD-YY (conflicts with YY-MM-DD), YYMMDD (conflicts with YYYYMM). Weekdays are now numbered 1-7 (mon-sun) instead of 0-6 (sun-sat) By default the week now starts with Monday instead of Sunday to meet ISO 8601. The FirstDay variable can be set to 7 to set Sunday as the first day. By default, the 1st week of the year contains Jan 4 (ISO 8601). See the Jan1Week1 variable for overriding this. ############################################################################ If you would like to stay informed about future versions of this module, and especially if you are interested in beta testing future versions, please let me know by email at: sbeck@cise.ufl.edu The newest version (which should be considered a beta version) is available through my home page: http://www.qtp.ufl.edu/~beck Feel free to try it out. The current (non-beta) version of this module is available from you nearest CPAN site and is NOT available from my home page. I will announce new (non-beta) releases in comp.lang.perl.misc and comp.lang.perl.announce. ############################################################################ This is a set of routines designed to make any common date/time manipulation easy to do. Operations such as comparing two times, calculating a time a given amount of time from another, or parsing international times are all easily done. Date::Manip deals only with the Gregorian calendar (the one currently in use). The Julian calendar defined leap years as every 4th year. The Gregorian calendar improved this by making every 100th year NOT a leap year, unless it was also the 400th year. The Gregorian calendar has been extrapolated back to the year 1000 AD and forward to the year 9999 AD. Note that in historical context, the Julian calendar was in use until 1582 when the Gregorian calendar was adopted by the Catholic church. Protestant countries did not accept it until later; Germany and Netherlands in 1698, British Empire in 1752, Russia in 1918. Note that the Gregorian calendar is itself imperfect. Each year is on average 26 seconds too long, which means that every 3,323 years, a day should be removed from the calendar. No attempt is made to correct for that. Date::Manip is therefore not equipped to truly deal with historacle dates, but should be able to perform (virtually) any operation dealing with a modern time and date. Among other things, Date::Manip allow you to: 1. Enter a date and be able to choose any format conveniant 2. Compare two dates, entered in widely different formats to determine which is earlier 3. Extract any information you want from ANY date using a format string similar to the Unix date command 4. Determine the amount of time between two dates 5. Add a time offset to a date to get a second date (i.e. determine the date 132 days ago or 2 years and 3 months after Jan 2, 1992) 6. Work with dates with dates using international formats (foreign month names, 12/10/95 referring to October rather than December, etc.). Each of these tasks is trivial (one or two lines at most) with this package. Although the word date is used extensively here, it is actually somewhat misleading. Date::Manip works with the full date AND time (year, month, day, hour, minute, second, and will ignore fractional seconds). In the documentation below, US formats are used, but in most (if not all) cases, a non-English equivalent will work equally well. EXAMPLES: 1. Parsing a date from any conveniant format $date=&ParseDate("today"); $date=&ParseDate("1st thursday in June 1992"); $date=&ParseDate("05/10/93"); $date=&ParseDate("12:30 Dec 12th 1880"); $date=&ParseDate("8:00pm december tenth"); if (! $date) { # Error in the date } 2. Compare two dates $date1=&ParseDate($string1); $date2=&ParseDate($string2); if ($date1 lt $date2) { # date1 is earlier } else { # date2 is earlier (or the two dates are identical) } 3. Extract information from a date. print &UnixDate("today","The time is now %T on %b %e, %Y."); => "The time is now 13:24:08 on Feb 3, 1996." 4. The amount of time between two dates. $date1=&ParseDate($string1); $date2=&ParseDate($string2); $delta=&DateCalc($date1,$date2,\$err); => 0:0:DD:HH:MM:SS the days, hours, minutes, and seconds between the two $delta=&DateCalc($date1,$date2,\$err,1); => YY:MM:DD:HH:MM:SS the years, months, etc. between the two Read the documentation in the man page for an explanation of the difference. 5. To determine a date a given offset from another. $date=&DateCalc("today","+ 3hours 12minutes 6 seconds",\$err); $date=&DateCalc("12 hours ago","12:30 6Jan90",\$err); It even works with business days: $date=&DateCalc("today","+ 3 business days",\$err); 6. To work with dates in another language. &Date_Init("Language=French","DateFormat=non-US"); $date=&ParseDate("1er decembre 1990"); NOTE: Some date forms do not work as well in languages other than English, but this is not because DateManip is incapable of doing so (almost nothing in this module is language dependent). It is simply that I do not have the correct translation available for some words. If there is a date form that works in English but does not work in a language you need, let me know and if you can provide me the translation, I will fix DateManip. For documentation on all of the date manipulation routines, read the man page. AUTHOR Sullivan Beck (sbeck@cise.ufl.edu)