[Zope3-dev] Re: datetimeutil.py for the rest of us

[Tres Seaver]

Terry Hancock wrote:
> On Sunday 30 May 2004 01:51 pm, Martijn Faassen wrote:
> 
>>Stuart Bishop wrote:
>>
>>>    - If an ambiguous datetime format is parsed, it assumes US format.
>>>      I feel that this case should instead raise an exception.
>>>      If US programmers insist on being able to write broken code,
>>>      seperate US specific methods could be made available in
>>>      datetimeutils.py or a seperate US centric module.
>>
>>I strongly agree that the datetime parser should *not* try to make sense 
>>of wrong data. If the format says mm-dd-yy and the date doesn't fit in 
>>it as it's dd-mm-yy, it should fail, and verse versa. I'm not the only 
>>one who has run into bugs (outside of Zope, mind) because people insist 
>>of doing it the Perl way and guess at it, instead of doing it the Python 
>>way and refusing to guess.
> 
> 
> Well, if you're going to assume a format, it seems more appropriate to
> assume *metric* order rather than either European or American. The metric
> standard says the numbers should be in decreasing order of significance,
> just like written decimal numbers.  Thus: YYYY-MM/DD.

The slash is what screws it up.  Try 'YYYY-MM-DD' and see if that works 
for you::

zopectl> debug
Starting debugger (the name "app" is bound to the top-level Zope object)
 >>> from DateTime.DateTime import DateTime
 >>> d = DateTime( '2000-01/02' )
Traceback (most recent call last):
   File "<stdin>", line 1, in ?
   File 
"/home/tseaver/projects/Zope-CVS/Zope-2.7-branch/lib/python/DateTime/DateTime.py", 
line 724, in __init__
     yr,mo,dy,hr,mn,sc,tz=self._parse_iso8601(arg)
   File 
"/home/tseaver/projects/Zope-CVS/Zope-2.7-branch/lib/python/DateTime/DateTime.py", 
line 1690, in _parse_iso8601
     raise SyntaxError, (
DateTime.DateTime.SyntaxError: Not an ISO 8601 compliant date string: 
"2000-01/02"
 >>> d = DateTime( '2000-01-02' )
 >>> d
DateTime('2000/01/02')
 >>> d.year
<bound method DateTime.year of DateTime('2000/01/02')>
 >>> d.year()
2000
 >>> d.month()
1
 >>> d.day()
2


> I always record dates that way.  DateTime doesn't read them right, though.
> (If "right" is the right word).  Generally it seems to me that the app
> programmer has to specifically ask for year, month, and day separately if
> they want to get correct results.

The-lovely-thing-about-standards'ly,

Tres.
-- 
===============================================================
Tres Seaver                                tseaver at zope.com
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