[Distutils] Finishing PEP 345

[Ned Deily]

In article 
<3476.218.214.45.58.1263173741.squirrel at syd-srv02.ezyreg.com>,
 "David Lyon" <david.lyon at preisshare.net> wrote:
> >From PEP-345,
> 
> > Requires-Dist: foo (1,!=1.3); platform.machine == 'i386'
[...] 
> So the test would be true for some macs but not all, depending on how old
> the mac is. Depending on whether the python implementation is properly
> working or not.
> 
> I'll just make the point that it is going to be really difficult for
> windows users to follow the hardware differences that exist in the mac
> world.
> 
> Obviously, some macs have intel processors and some don't. How would a
> developer reasonably be expected to know which are which? and what
> difference does it make?
> 
> This information needs to be covered in the PEP for it to make it make
> more sense to mr.average developer. At the moment it is somewhat
> confusing.

In practice, this is seldom an issue on OS X as Pythons supplied by 
python.org and Apple are supplied as multi-architecture executables, 
i.e. the same file contains binaries for both 32-bit Intel and PPC CPUs 
and, in some cases, 64-bit Intel and 64-bit PPC as well.  The 
Apple-supplied build tool chain, and some code in the Python build 
scripts and Distutils, normally takes care of everything when building 
Python C extensions modules with no user intervention needed.  So there 
would almost never be a case where a platform.machine test would be 
needed for OS X.

-- 
 Ned Deily,
 nad at acm.org