[Python-Dev] Re: Request to postpone some Python 3.9 incompatible changes to Python 3.10

[Steve Dower]

On 25Jan.2020 0348, Guido van Rossum wrote:
> On Fri, Jan 24, 2020 at 12:12 AM Serhiy Storchaka  > wrote:
> 
> I consider breaking unmaintained code is an additional benefit of
> removing deprecated features.
> 
> 
> I'd like to warn against this attitude (even though in the past I've
> occasionally said such things). I now  think core Python should not be
> so judgmental. We've broken enough code for a lifetime with the Python 2
> transition. Let's be *much* more conservative when we remove things from
> Python 3. Deprecation is fine, and we should look for other ways to
> handle the problem of unmaintained code. But we should not rush language
> or stdlib changes for this purpose.

I'd like to *strongly* agree with this sentiment.

Marking things as deprecated when we don't like them is a perfectly good
way to advise against their use (and give ourselves permission to let
bit-rot set in). But unless they are an actual maintenance burden, we
gain literally nothing by removing them, and actively hurt our
already-hurting users.

As much as we know that 3.x->3.y is a major version change, many of our
users don't think of them like that (in part because they come out so
often). The more we can keep things working between them, warts or not,
the better.

Cheers,
Steve
___
Python-Dev mailing list -- python-dev@python.org
To unsubscribe send an email to python-dev-le...@python.org
https://mail.python.org/mailman3/lists/python-dev.python.org/
Message archived at 
https://mail.python.org/archives/list/python-dev@python.org/message/IYQNATVOQ5XVVMZPXTZMTS5JLRGAO2BV/
Code of Conduct: http://python.org/psf/codeofconduct/

[Python-Dev] extern "C" { ... } in Include/cpython/*.h

[Skip Montanaro]

(Apologies. Not sure where to ask this, and I'm not much of a C++
programmer. Maybe I should have just added a comment to the still-open
issue.)

I just noticed that Nick migrated the guts of Include/frameobject.h to
include/cpython/frameobject.h. It's not clear to me that the latter
should be #include'd directly from anywhere other than
Include/frameobject.h. If that's the case, does the extern "C" stuff
still need to be replicated in the lower level file? Won't the scope
of the extern "C" block in Include/frameobject.h be active at the
lower level?

Whatever the correct answer is, I suspect the same constraints should
apply to all Include/cpython/*.h files.

Skip
___
Python-Dev mailing list -- python-dev@python.org
To unsubscribe send an email to python-dev-le...@python.org
https://mail.python.org/mailman3/lists/python-dev.python.org/
Message archived at 
https://mail.python.org/archives/list/python-dev@python.org/message/CQATW7HLURFFZDCEZRKFWHPSEPO7SDSZ/
Code of Conduct: http://python.org/psf/codeofconduct/

[Python-Dev] Re: Request to postpone some Python 3.9 incompatible changes to Python 3.10

[Barry Scott]

> On 24 Jan 2020, at 08:40, Victor Stinner  wrote:
> 
> The change is that Python 2.7 is no longer supported (since 2020-01-01).
> 

Isn't there going to be a final Python 2.7 release in April 2020?

I know that Twisted has moved its python 2 removal to match the
April 2020 date. Other projects may have made the similar decisions.

Barry




> Victor
> 
> Le ven. 24 janv. 2020 à 09:19, Chris Angelico  a écrit :
>> 
>> On Fri, Jan 24, 2020 at 7:05 PM Victor Stinner  wrote:
>>> We kept a compatibility layer with Python 2 on purpose, PEP 4 says:
>>> 
>>> "In order to facilitate writing code that works in both Python 2 & 3
>>> simultaneously, any module that exists in both Python 3.5 and Python
>>> 2.7 will not be removed from the standard library until Python 2.7 is
>>> no longer supported as specified by PEP 373."
>>> 
>>> The rule was used since Python 3.0 until Python 3.8, but it changed in
>>> Python 3.9 which includes many incompatible changes for the first time
>>> in the Python 3 major version.
>> 
>> I'm sorry, I don't understand what 'changed'. Isn't that rule exactly
>> WHY 3.9 is the removal point? Python 2.7 is no longer supported, and
>> its final post-support release is scheduled earlier than 3.9's first
>> beta and feature freeze. Doesn't that mean that PEP 4 is being
>> followed precisely? What have I misunderstood?
>> 
>> ChrisA
>> ___
>> Python-Dev mailing list -- python-dev@python.org
>> To unsubscribe send an email to python-dev-le...@python.org
>> https://mail.python.org/mailman3/lists/python-dev.python.org/
>> Message archived at 
>> https://mail.python.org/archives/list/python-dev@python.org/message/GCCLU2O2QJTGECQKUYEHD2KVD3IKJTLE/
>> Code of Conduct: http://python.org/psf/codeofconduct/
> 
> 
> 
> -- 
> Night gathers, and now my watch begins. It shall not end until my death.
> ___
> Python-Dev mailing list -- python-dev@python.org
> To unsubscribe send an email to python-dev-le...@python.org
> https://mail.python.org/mailman3/lists/python-dev.python.org/
> Message archived at 
> https://mail.python.org/archives/list/python-dev@python.org/message/6YLZXTOJJ7XGISGRITJV7OAEOEKFYZS7/
> Code of Conduct: http://python.org/psf/codeofconduct/
___
Python-Dev mailing list -- python-dev@python.org
To unsubscribe send an email to python-dev-le...@python.org
https://mail.python.org/mailman3/lists/python-dev.python.org/
Message archived at 
https://mail.python.org/archives/list/python-dev@python.org/message/C65AAFHWSN46SI5NBF735MPF242NRSQC/
Code of Conduct: http://python.org/psf/codeofconduct/

[Python-Dev] Re: Request to postpone some Python 3.9 incompatible changes to Python 3.10

[Victor Stinner]

See pyfound.blogspot.com/2019/12/python-2-sunset.html for the details.

January or April doesn't matter much for this thread, since Python
3.9.0 final is scheduled for October.

Victor

Le lun. 27 janv. 2020 à 23:13, Barry Scott  a écrit :
>
>
>
> > On 24 Jan 2020, at 08:40, Victor Stinner  wrote:
> >
> > The change is that Python 2.7 is no longer supported (since 2020-01-01).
> >
>
> Isn't there going to be a final Python 2.7 release in April 2020?
>
> I know that Twisted has moved its python 2 removal to match the
> April 2020 date. Other projects may have made the similar decisions.
>
> Barry
>
>
>
>
> > Victor
> >
> > Le ven. 24 janv. 2020 à 09:19, Chris Angelico  a écrit :
> >>
> >> On Fri, Jan 24, 2020 at 7:05 PM Victor Stinner  wrote:
> >>> We kept a compatibility layer with Python 2 on purpose, PEP 4 says:
> >>>
> >>> "In order to facilitate writing code that works in both Python 2 & 3
> >>> simultaneously, any module that exists in both Python 3.5 and Python
> >>> 2.7 will not be removed from the standard library until Python 2.7 is
> >>> no longer supported as specified by PEP 373."
> >>>
> >>> The rule was used since Python 3.0 until Python 3.8, but it changed in
> >>> Python 3.9 which includes many incompatible changes for the first time
> >>> in the Python 3 major version.
> >>
> >> I'm sorry, I don't understand what 'changed'. Isn't that rule exactly
> >> WHY 3.9 is the removal point? Python 2.7 is no longer supported, and
> >> its final post-support release is scheduled earlier than 3.9's first
> >> beta and feature freeze. Doesn't that mean that PEP 4 is being
> >> followed precisely? What have I misunderstood?
> >>
> >> ChrisA
> >> ___
> >> Python-Dev mailing list -- python-dev@python.org
> >> To unsubscribe send an email to python-dev-le...@python.org
> >> https://mail.python.org/mailman3/lists/python-dev.python.org/
> >> Message archived at 
> >> https://mail.python.org/archives/list/python-dev@python.org/message/GCCLU2O2QJTGECQKUYEHD2KVD3IKJTLE/
> >> Code of Conduct: http://python.org/psf/codeofconduct/
> >
> >
> >
> > --
> > Night gathers, and now my watch begins. It shall not end until my death.
> > ___
> > Python-Dev mailing list -- python-dev@python.org
> > To unsubscribe send an email to python-dev-le...@python.org
> > https://mail.python.org/mailman3/lists/python-dev.python.org/
> > Message archived at 
> > https://mail.python.org/archives/list/python-dev@python.org/message/6YLZXTOJJ7XGISGRITJV7OAEOEKFYZS7/
> > Code of Conduct: http://python.org/psf/codeofconduct/
>


-- 
Night gathers, and now my watch begins. It shall not end until my death.
___
Python-Dev mailing list -- python-dev@python.org
To unsubscribe send an email to python-dev-le...@python.org
https://mail.python.org/mailman3/lists/python-dev.python.org/
Message archived at 
https://mail.python.org/archives/list/python-dev@python.org/message/YIFL5OANIFXSSR7LHT2FCQZWNTFZWY26/
Code of Conduct: http://python.org/psf/codeofconduct/

[Python-Dev] Re: Request to postpone some Python 3.9 incompatible changes to Python 3.10

[Miro Hrončok]

On 24. 01. 20 16:22, Eric V. Smith wrote:

On 1/24/2020 9:14 AM, Miro Hrončok wrote:

On 24. 01. 20 14:02, Eric V. Smith wrote:
I think the concern is that with removing so many deprecated features, we're 
effectively telling libraries that if they want to support 3.9, they'll have 
stop supporting 2.7. And many library authors aren't willing to do that yet. 
Will they be willing to in another year? I can't say.


The concern is not that they don't want to drop 2.7 support, but that is is a 
nontrivail task to actaually do and we cannot expect them to do it within the 
first couple weeks of 2020. While at the same time, we want them to support 
3.9 since the early development versisons in order to eb able to detect 
regressions early in the dev cycle.


Ah. So in 3.8, they kept code that had deprecation warnings so that they could 
be compatible with 2.7. They'd like to now drop that code and be 3.9-only 
compatible, but they don't have enough time to do that because they couldn't 
start that work as long as they were supporting 2.7. Do I have that right?


Yes.

If so, I'd be okay with postponing the removal of the deprecated code until 
3.10. But I don't think we should postpone it if the driver is so that libraries 
can remain 2.7 compatible. That could go on forever. This postponement would be 
a one-time thing.


--
Miro Hrončok
--
Phone: +420777974800
IRC: mhroncok
___
Python-Dev mailing list -- python-dev@python.org
To unsubscribe send an email to python-dev-le...@python.org
https://mail.python.org/mailman3/lists/python-dev.python.org/
Message archived at 
https://mail.python.org/archives/list/python-dev@python.org/message/ZKVPNSAX5NPTWVOD6Y6FLBBLZWFIXUVN/
Code of Conduct: http://python.org/psf/codeofconduct/

[Python-Dev] Re: Request to postpone some Python 3.9 incompatible changes to Python 3.10

[Miro Hrončok]

On 24. 01. 20 22:54, Serhiy Storchaka wrote:

23.01.20 17:20, Victor Stinner пише:

 > * Removed collections aliases to ABC classes

Adding loud warning was one of largest compatibility breaking changes in 3.8, 
because many active projects treat warnings in tests as errors. I had doubts 
about removing them. On one side, they were deprecated for a very long time. On 
other side, most time it was silent deprecation, and the removal will affect too 
much projects. I agree with deferring this removal.


Some data points:

This has so far affected ~65 from ~200 projects that we found fail to build in 
Fedora w/3.9.



 > * Remove "U" mode of open(): having to use io.open() just for Python 2
 > makes the code uglier


~10


* Removed tostring/fromstring methods in array.array and base64 modules


~10


* Removed fractions.gcd() function (which is similar to math.gcd())


0


* Removed old plistlib API: 2.7 doesn't have the new API


2

--
Miro Hrončok
--
Phone: +420777974800
IRC: mhroncok
___
Python-Dev mailing list -- python-dev@python.org
To unsubscribe send an email to python-dev-le...@python.org
https://mail.python.org/mailman3/lists/python-dev.python.org/
Message archived at 
https://mail.python.org/archives/list/python-dev@python.org/message/LGGI42UEQMJVNW2ZHEP473Z7ZQ5BDBPL/
Code of Conduct: http://python.org/psf/codeofconduct/

[Python-Dev] Re: Request to postpone some Python 3.9 incompatible changes to Python 3.10

[Terry Reedy]

On 1/27/2020 4:56 PM, Barry Scott wrote:

On 24 Jan 2020, at 08:40, Victor Stinner  wrote:
The change is that Python 2.7 is no longer supported (since 2020-01-01).

Isn't there going to be a final Python 2.7 release in April 2020?


Normal patching has stopped, much as if the final .rc1 release candidate 
had been issued.  I believe Benjamin want to hit the final release 
button live at PyCon.


--
Terry Jan Reedy
___
Python-Dev mailing list -- python-dev@python.org
To unsubscribe send an email to python-dev-le...@python.org
https://mail.python.org/mailman3/lists/python-dev.python.org/
Message archived at 
https://mail.python.org/archives/list/python-dev@python.org/message/PKQ3LXXCQGXGQ2QHL5PMLQSWJCVD3Z52/
Code of Conduct: http://python.org/psf/codeofconduct/

[Python-Dev] Re: Request to postpone some Python 3.9 incompatible changes to Python 3.10

[Barry Warsaw]

On Jan 27, 2020, at 13:56, Barry Scott  wrote:
> 
> Isn't there going to be a final Python 2.7 release in April 2020?

Yes, but I’ve been calling it a “celebratory release”.  We’re gonna party at 
Pycon like it’s 2000.

-Barry



signature.asc
Description: Message signed with OpenPGP
___
Python-Dev mailing list -- python-dev@python.org
To unsubscribe send an email to python-dev-le...@python.org
https://mail.python.org/mailman3/lists/python-dev.python.org/
Message archived at 
https://mail.python.org/archives/list/python-dev@python.org/message/FHK5X2XNPXZC2CSZ424XBOZTMAEUJ2IN/
Code of Conduct: http://python.org/psf/codeofconduct/