Calendar Types
Seth Kurtzberg
seth at cql.com
Mon Feb 14 16:11:03 EST 2005
Glynn Clements wrote:
>Bayley, Alistair wrote:
>
>
>
>>>You also need to specify, or let the user specify, the order of
>>>arithmetic. I.e. adding a day and then a second is different from
>>>doing it the other way around.
>>>
>>>
>
>Only when leap seconds are involved. A month and a day would be a
>better example.
>
>
>
>>Duration arithmetic is not commutative? Can you give some examples please,
>>because I'm not able to imagine any.
>>
>>
>
> April 30th + 1 month + 1 day = May 30th + 1 day = May 31st
> April 30th + 1 day + 1 month = May 1st + 1 month = June 1st
>
>
What reason is there to say May 30 + 1 day == May 31st? May 30 + 1 day
= June first. So the answer is the same either way, as long as your
result for May 30 + 1 day is correct.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.haskell.org//pipermail/libraries/attachments/20050214/2a72fe15/attachment.htm
More information about the Libraries
mailing list