[Zope] Strange date handling problems

[Jim Fulton]

There have been a number of changes to DateTime since Zope 1.9.
Many of these related to numeric/date conversion and math.

We are going to make a 1.10 pre-release today.  Please see if the
new DateTime gives you any trouble.  It did the right thing
for me with the expressions below.

Jim

Ty Sarna wrote:
> 
> I'm getting unexpected results when doing computations on DateTime
> instances. For example, the following should always result in 'd' being the
> first of the previous month to 'date':
> 
> d = date - date.day()           #       1999/5/14 - 13 = 1999/4/30
> d = d - (d.day() - 1)           #       1999/4/30 - (30 - 1) =
>                                 #       1999/4/30 - 29 = 1999/4/1
> 
> Thie works great, unless 'date' is in May, in which case I end up with
> 1999/3/31 instead. A similar computation to find the first of the next
> month also gives strange results if the start date is in March. In other
> words, if the correct result is April Fool's, I get something else
> instead!
> 
> Another, more involved set of calculations gives incorrect results for
> most dates in October, but is fine for any other month. What's going on?
> 
> _______________________________________________
> Zope maillist  -  Zope@zope.org
> http://www.zope.org/mailman/listinfo/zope


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