Re: [boost] Date/Time Classes

From: George A. Heintzelman (georgeh_at_[hidden])
Date: 2001-03-22 09:30:00

> Speaking of implementation independent timing classes reminded me that I
> will very shortly be needing some way of representing dates and times in a
> project I am working on. Does anyone have any recomendations? This is the
> sort of library I would have thought would be ideal for boost.

I think this would be great to have standardized, even at the standard 
time() granularity of one second. I've seen many tries at such classes, 
none of them wholly satisfactory. A few things that I have observed 
which I think should be taken into account in any such classes:

1) It should be as independent of other services (say, calendaring) as 
possible. Lightweight is quite important here. However, it should be 
easy to attach things like, adding one business day to a date to the 
basic class without fuss and muss.
2) There is a definite need for dates without times and times without 
dates. Often one wants to test dates for equality without worrying 
about whether the seconds match up; often one wants to represent that, 
say, the NYSE is open from 9:30 AM to 4 PM.
3) Timezone issues are a real sticky problem. Speaking off-the-cuff, I 
think that what should be done is that the internal data for a 
particular instant should be timezone-independent, with a 
locale-dependent translation to date-only, time-only or text-based 
representations. Effort will have to be spent making sure that the only 
people who have to worry about timezone issues are people who, well, 
have to worry about timezone issues anyway (doing business across 
timezones and so forth).
4) It is absolutely essential to have many (preferably potentially 
user-defined) ways of presenting and reading a text-based 
representation. A lot of effort will need to be spent on stream 
manipulators to achieve this. This is because virtually every 
client-server system which sends date/time information uses a slightly 
different representation for its 'standard form'.

If you build it, they will come. Or at least I will!

George Heintzelman
georgeh_at_[hidden]