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56 lines
2.4 KiB
Plaintext
56 lines
2.4 KiB
Plaintext
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This is a set of routines designed to make any common
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date/time manipulation easy to do. Operations such as
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comparing two times, calculating a time a given amount of
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time from another, or parsing international times are all
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easily done.
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Date::Manip deals only with the Gregorian calendar (the
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one currently in use). The Julian calendar defined leap
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years as every 4th year. The Gregorian calendar improved
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this by making every 100th year NOT a leap year, unless it
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was also the 400th year. The Gregorian calendar has been
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extrapolated back to the year 1000 AD and forward to the
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year 9999 AD. Note that in historical context, the Julian
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calendar was in use until 1582 when the Gregorian calendar
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was adopted by the Catholic church. Protestant countries
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did not accept it until later; Germany and Netherlands in
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1698, British Empire in 1752, Russia in 1918. Note that
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the Gregorian calendar is itself imperfect. Each year is
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on average 26 seconds too long, which means that every
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3,323 years, a day should be removed from the calendar.
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No attempt is made to correct for that.
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Date::Manip is therefore not equipped to truly deal with
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historacle dates, but should be able to perform
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(virtually) any operation dealing with a modern time and
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date.
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Among other things, Date::Manip allow you to:
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1. Enter a date and be able to choose any format
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conveniant
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2. Compare two dates, entered in widely different formats
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to determine which is earlier
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3. Extract any information you want from ANY date using a
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format string similar to the Unix date command
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4. Determine the amount of time between two dates
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5. Add a time offset to a date to get a second date (i.e.
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determine the date 132 days ago or 2 years and 3 months
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after Jan 2, 1992)
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6. Work with dates with dates using international formats
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(foreign month names, 12-10-95 referring to October rather than
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December, etc.).
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Each of these tasks is trivial (one or two lines at most)
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with this package.
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Although the word date is used extensively here, it is
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actually somewhat misleading. Date::Manip works with the
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full date AND time (year, month, day, hour, minute,
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second).
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