[Cython] Shared Cython runtime (was: Upcoming cython/numpy breakage with stride checking)

[Stefan Behnel]

mark florisson, 09.04.2013 15:13:
> On 9 April 2013 14:11, Stefan Behnel wrote:
>> Nathaniel Smith, 09.04.2013 15:00:
>>> On 9 Apr 2013 13:50, "Stefan Behnel" wrote:
>>>> There's also the problem of dependency hell and getting rid of old
>>>> modules
>>>> once they are no longer used on the user side. And also, how to get them
>>>> there in the first place. Having one package overwrite the files of
>>>> another during its installation is just asking for trouble.
>>>
>>> The system I described does not involve the addition of any new files to
>>> any package.
>>
>> I take it then that you were envisaging a separate "cython-runtime" package
>> on PyPI that Cython compiled modules would have to depend on?
>>
>> As long as people install their stuff using pip, that could work for them
>> mostly ok, although with the regrettable Cython user impact of having to
>> set that dependency for their packages in the first place.
>>
>> If people want to install stuff manually, dependency hell gets close.
>>
>> Or did you see any other ways of getting these things installed
>> automatically, with a smaller user impact?
> 
> For reference, here's a CEP about this written last year:
> http://wiki.cython.org/enhancements/libcython

Ok, but that CEP excludes the rather vital problem of distribution and
installation. I also fail to see a reference to the problem of how multiple
modules will interact that use different Cython runtime versions. That's a
substantially bigger problem once symbols start becoming externally visible.

Stefan