[issue17267] datetime.time support for '+' and '-'

Martin Panter added the comment: A real use case that I have had was with a protocol to activate a device with a daily schedule. The protocol takes start and end hours and minutes of the day. To test the device by activating it over the next few minutes, my ideal way would have taken the

[issue17267] datetime.time support for '+' and '-'

Change by Andreas Åkerlund : -- nosy: -thezulk ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue17267] datetime.time support for '+' and '-'

Change by Skip Montanaro : -- nosy: -skip.montanaro ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue17267] datetime.time support for '+' and '-'

Paul Ganssle added the comment: I am pretty neutral on this. I don't think it will be terribly difficult to implement or maintain this, and while there are a few possible behaviors, if you think about it for a bit, addition with overflow behavior *does* seem like the natural way to

[issue17267] datetime.time support for '+' and '-'

Change by Karthikeyan Singaravelan : -- nosy: +p-ganssle ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue17267] datetime.time support for '+' and '-'

Cheryl Sabella added the comment: It seems that there was interest in this enhancement a few years ago. @joar, would you be able to convert your patch to a GitHub pull request on the master branch? Thanks! -- nosy: +cheryl.sabella versions: +Python 3.8 -Python 3.4

[issue17267] datetime.time support for '+' and '-'

Changes by R. David Murray rdmur...@bitdance.com: -- nosy: +r.david.murray ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue17267 ___ ___

[issue17267] datetime.time support for '+' and '-'

Alexander Belopolsky added the comment: I think the timezone related problems are a red herring. Aware datetime +/- timedelta arithmetics is naive - tzinfo is ignored in calculations and copied to the result: http://hg.python.org/cpython/file/c83ce2a1841c/Lib/datetime.py#l1711 The utcoffset

[issue17267] datetime.time support for '+' and 'now'

Alexander Belopolsky added the comment: I left a few minor comments on rietveld for the last patch. I did not see code for time.now() and I don't think adding now() should be combined with time +/- timedelta patch. Let's do one thing at a time. I think time + timedelta addition is fairly

[issue17267] datetime.time support for '+' and 'now'

Alexander Belopolsky added the comment: This was proposed before and rejected in issue1118748, but I think current proposal addresses the ambiguity that was sited as a reason for rejection. -- nosy: +skip.montanaro ___ Python tracker

[issue17267] datetime.time support for '+' and 'now'

Alexander Belopolsky added the comment: See also issue 3250. If we add mod 24h arithmetics, I would like to see something like time.add_with_carry(timedelta) - (int, time) method. With it, users who need a specific overflow behavior will be able to implement it easily: def check_add(t, td):

[issue17267] datetime.time support for '+' and '-'

Alexander Belopolsky added the comment: I am changing the title to focus this issue on arithmetics. Lack of time.now() is adressed in #8902. -- title: datetime.time support for '+' and 'now' - datetime.time support for '+' and '-' ___ Python

[issue17267] datetime.time support for '+' and 'now'

Francisco Martín Brugué added the comment: Hi Joar, just a detail: is there a reason for the asymmetric check for timedelta isinstance (and raising NotImplemented)? And BTW. isn't a double check for the __sub__ case (or have I missed something)? +def __add__(self, other): +Add a

[issue17267] datetime.time support for '+' and 'now'

jbatista added the comment: IMHO this should be safe when the timezone is UTC for example, where there is no problems with daylight savings. What should be the behavior when adding a certain timedelta() and it crosses a date where there is an hour switch due to daylight savings? The unadvised

[issue17267] datetime.time support for '+' and 'now'

Ronald Oussoren added the comment: datetime.time arithmetic cannot be timezone aware, as there is no associated date and hence you cannot possibly know if there it a DST transition. I don't think this is a problem. Adding/removing time to a clock value has clear real-world semantics. Using

[issue17267] datetime.time support for '+' and 'now'

Petri Lehtinen added the comment: A time object isn't associated with any date, so I don't really see a problem here. The fact that you can shoot yourself in the leg can be documented, noting that you should use datetime instead. ISTM the reason why time objects even have an associated timezone

[issue17267] datetime.time support for '+' and 'now'

Joar Wandborg added the comment: New patch, removed whitespace change and unnecessary test. add_time_timedelta arg `factor` will not be changed, in order to preserve uniformity. -- Added file: http://bugs.python.org/file29251/issue17267-v3.patch

[issue17267] datetime.time support for '+' and 'now'

Petri Lehtinen added the comment: LGTM. -- stage: test needed - patch review ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue17267 ___ ___

[issue17267] datetime.time support for '+' and 'now'

Changes by Ronald Oussoren ronaldousso...@mac.com: -- keywords: +needs review nosy: +belopolsky ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue17267 ___

[issue17267] datetime.time support for '+' and 'now'

Joar Wandborg added the comment: I am adding yet another patch. This time it has - TZ-aware tests (datetimetester.TestTimeTZ). - C time_subtract method. - Pure time.__sub__ method. in addition to the previous - Tests for time + timedelta - C time_add - Pure time.__add__ There's one issue

[issue17267] datetime.time support for '+' and 'now'

Changes by Michele Orrù maker...@gmail.com: -- nosy: +maker ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue17267 ___ ___ Python-bugs-list mailing

[issue17267] datetime.time support for '+' and 'now'

Joar Wandborg added the comment: Patch submitted, please review. -- keywords: +patch nosy: +joar Added file: http://bugs.python.org/file29200/issue17267.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue17267

[issue17267] datetime.time support for '+' and 'now'

Petri Lehtinen added the comment: Added some comments to Rietveld. -- nosy: +petri.lehtinen ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue17267 ___

[issue17267] datetime.time support for '+' and 'now'

Joar Wandborg added the comment: New patch adressing the review comments. -- Added file: http://bugs.python.org/file29205/issue17267.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue17267

[issue17267] datetime.time support for '+' and 'now'

Andreas Åkerlund added the comment: Well I have also made a patch for this, using the datetime operator code as much as possible.. this is for version 3.4.. -- nosy: +thezulk Added file: http://bugs.python.org/file29206/issue17267-3.4.diff ___

[issue17267] datetime.time support for '+' and 'now'

New submission from Ronald Oussoren: It would be nice if datetime.time would be possible to add a delta to a datetime.time object, and if datetime.time had a method for returning the current time (just like datetime.date and date time.datetime have 'today' and 'now' methods). Rationale for

[issue17267] datetime.time support for '+' and 'now'

Eric V. Smith added the comment: What would this give: tm = datetime.time(13, 20) later = tm + datetime.timedelta(hours=47, minutes=44) datetime.time(13, 4)? Or raise an exception? I've thought about this before, but it's always a problem when going over date boundaries. If you define

[issue17267] datetime.time support for '+' and 'now'

Ronald Oussoren added the comment: IMHO this would to module 24 arithmetic, just like a normal clock. When I do calculations with plain time that is what I want, if the date is also important I use datetime.datetime. That a time value silently truncates when going past midnight is IMHO also