Re: Software Engineering News Brief

[eggert@twinsun.com (Paul Eggert)]

eachus@spectre.mitre.org (Robert I. Eachus) writes:

> 1901 to 2099 is the longest
> span possible without requiring implementors to include a leap year
> rule that has never been used in practice.

Actually, many kinds of applications require support for dates outside
that range; it was shortsighted of the Ada standard-writers to prohibit
implementations from having better standard date support than that.

>    I'm sure that the next version of Ada will support a longer range
>of dates, but I doubt that it will go too far back.  In fact, there
>are areas where Gregorian dates from the beginning of this century are
>nonsense

... which is why the next version of Ada should support Gregorian dates
all the way back to at least the year 1, if not before.  Trying to
match the historical introduction of the Gregorian calendar
leads to severe politico-technical problems.  For an example of this
see my May 1995 comp.risks article about Sybase's historically naive
practice of arbitrarily rejecting Gregorian dates before 1753.