Re: Please test gub

[Alexander Kobel]

Hi,

On 31.01.19 15:21, David Kastrup wrote:
> Knut Petersen <address@hidden> writes:
>
> > On 31.01.19 08:43, Alexander Kobel wrote:
> > > Hi,
> > >
> > > fails on Arch Linux (up-to-date, Intel Core i5-3317U).
> > >
> > > First, all Python scripts seem to require Python2 (but python ->
> > > python3 is the default on Arch).
>
> I don't think that matches Python's own recommendation.  Has this
> changed?

Kind of, yes, but then again, no, not really, it turns out. Lucky 
buzzwords for Google gave me PEP 394:
  https://www.python.org/dev/peps/pep-0394/

Relevant is the abstract, which in fact mentions that Arch, 
specifically, switched "early", broke the former practice (and, 
apparently, implicit and unwritten recommendation) and thus raised the 
discussion that led to PEP 394. It also says that "for the time being, 
all distributions should ensure that python, if installed, refers to the 
same target as python2, unless [...]".

*Also* relevant *now*, however, are the following point(s) from the 
recommendation:

"In order to tolerate differences across platforms, all new code that 
needs to invoke the Python interpreter should not specify python, but 
rather should specify either python2 or python3 (or the more specific 
python2.x and python3.x versions; see the Migration Notes). This 
distinction should be made in shebangs, when invoking from a shell 
script, when invoking via the system() call, or when invoking in any 
other context."

and

"In order to tolerate differences across platforms, all new code that 
needs to invoke the Python interpreter should not specify python, but 
rather should specify either python2 or python3 (or the more specific 
python2.x and python3.x versions; see the Migration Notes). This 
distinction should be made in shebangs, when invoking from a shell 
script, when invoking via the system() call, or when invoking in any 
other context."


I second the recommendation: as a happy year-long Archer, python 
shebangs are, by far, the number 1 of annoyances I encounter regularly. 
Whenever I can, I "correct" shebangs to python2 (without ever having 
looked up this PEP), and nobody ever complained that it breaks their 
workflow.
On the other hand, I still occasionally use systems with Python2 <2.7 
(strictly less than). Hence, I'd refrain from specifying a minor version 
if it can be avoided. AFAIK, 2.8 is promised to never appear, so it 
shouldn't matter for 2.x. And I don't have 3.y for y < 7 available on my 
system; yet, 3.3 scripts run perfectly albeit the author might not have 
thought about that version when writing the script.


Cheers,
Alex

smime.p7s
Description: S/MIME Cryptographic Signature