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As a special exception from the GPL, if other files instantiate generics from this unit, or you link this unit with other files to produce an executable, this unit does not by itself cause the resulting executable to be covered by the GPL. This exception does not however invalidate any other reasons why the executable file might be covered by the GPL.

Version: 1.1

Author:

Thomas Wolf (TW) <twolf AT acm DOT org>

Purpose:

This is a mixed proleptic Julian (for dates prior to and including 4-OCT-1582 A.D.) and Gregorian (for dates from 15-OCT-1582 on) calendar, i.e. the calendar used in the western world, if we ignore the chaotic differences in the times the Gregorian calendar was actually adopted and the Romans' early counting error that caused every third year from 45 B.C. to 8 B.C. be a leap year (which was then corrected by not having any leap years at all from 7 B.C. until 8 A.D., which again was a leap year).

By the way, note that the day of the week did not change in Oct 1582, Oct 4 was a Thursday, and Oct 15 was a Friday! (And so is, of course, Oct 5, 1582 A.D. in the Julian calendar.)

Because not all countries and regions adopted the Gregorian calendar in 1582 (notably many protestant areas switched much later, and some orthodox regions didn't switch until the 20th century), you can define the switch date. By default, it is set to 4-OCT-1582.

Tasking Semantics

Neither task- nor abortion-safe.

Storage Semantics

No dynamic storage allocation.