[Python-Dev] Providing support files to assist 3.x extension authors

[Case Vanhorsen]

On Sun, Dec 20, 2009 at 12:49 AM, "Martin v. Löwis" <martin at v.loewis.de> wrote:
>> Several questions come to mind:
>>
>> 1) Is it reasonable to provide backward compatibility files (either as
>> .h or .c) to provide support to new API calls to extension authors?
>
> I'm skeptical. In my experience, each extension has different needs, and
> will also use different strategies to provide compatibility. So
> publishing one way as the "official" approach might be difficult. In one
> case, the proposed approach for compatibility actually led to incorrect
> code (by ignoring exceptions when extracting a long), so we would need
> to be fairly careful what compatibility layers we can bless as official.
>
>> 2) If yes, should they be included with the Python source or
>> distributed as a separate entity? (2to3 and/or 3to2 projects, a Wiki
>> page)
>
> In the way you propose it (i.e. as forward compatibility files) I fail
> to see the point of including them with Python 2.7. Extension authors
> likely want to support versions of Python before that, which now cannot
> be changed. So those authors would still have to include the file
> on their own.
>
> So a file distributed in Include of 2.7 actually hurts, as it would
> conflict with the copy included in packages.
>
>> 3) If not, and extension authors can create their own compatibility
>> files, are there any specific attribution or copyright messages that
>> must be included?
>
> If you write a compatibility file from scratch, without copying existing
> code, you don't need to worry at all. If you do copy parts of Python,
> you must follow the license, in particular clause 2.
>
> Regards,
> Martin
>

Thanks for comments. I will just maintain my own version.

Case