FreeBSD Port: py27-qt5-core / Py36-qt5-core

[Rainer Hurling]

Hi D.-C. M., hi others,

Am 27.03.2018 um 23:49 schrieb Guido Falsi:
> On 03/27/18 22:44, D.-C. M. wrote:
>> Hello,
>>
> 
> Hi!
> 
>>   
>>
>> At this moment, it is impossible to build side by side py27-qt5-core and
>> py36-qt5-core.
>>
>>   
>>
>> There is a collison on /usr/local/bin/pyuic
>>
>>   
>>
>> This is annoying… Python 27 is still the default, but become quite old now.
>>
> 
> I'm not a python expert, but I understand that python 2.7 and python 3
> are two slightly different languages not fully compatible with each other.
> 
> I also understand(but have not gone into depth about this) that there is
> some resistance to python 3, with many developers being reluctant to
> move to version 3, for whatever reason(I imagine it's language design
> choices, but I really don't know)
> 
> I'm stating this because it means such incompatibilities are not going
> away easily. It's not just a ports system problem, but an actual python
> ecosystem problem.
> 
> Too say it in other words, python 2.7 isn't really just "the old
> version" and python 3 is not just "the new version". They have parallel
> lifes.
> 
> 
>> deskutils/calibre
>>
>> which requires py27-qt5-core
>>
>> I have tried to modify Makefile to try to build calibre-ebook port
>> versus py36, but there seems to be a hard dependency to Python 27, as
> 
> calibre is programmed for python 2.7 and the original author has no plan
> to update it to work with python 3:
> 
> https://bugs.launchpad.net/calibre/+bug/1456642
> 
> This is in relation to what I said above.
> 
>>
>>   
>>
>> www/py-mechanize does not not exist in py36 flavor
> 
> It's not just a dependency problem. Calibre code depends on python 2.7
> language peculiarities which are different in python 3 (again I don't
> know the details)
> 
>>
>>   
>>
>> I would guess that it could be possible to differentiate the name of binary
>>
>> /usr/local/lib/pyuic
> 
> This would not suffice to fix the problem you're seeing.
> 
>>
>>   
>>
>> According to Py27 / Py36 flavor, with some strap.
>>
>> In fact, most of py27-xx/py36-xx can build side by side, but not py-qt5-core

There are some PRs about this[1][2]

[1] https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=219641
[2] https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=223764

In comment #33 of PR 219641 I suggested a possible change. This would be 
'double flavored' (QT[45] and py[45] at the same ports), which could be 
a problem with the design of flavors. Also, it is not tested very well.


> 
> And that's a problem since packages downstream from py-qt5-core strictly
> require python 2.7 or 3 and can't switch from one to another, but as I
> said, that's a python problem.
>