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

[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

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.

-- 
Guido Falsi <madpilot at FreeBSD.org>