[Python-Dev] Deprecating C APIs (Use of PyArg_NoArgs()) (original) (raw)

M.-A. Lemburg mal@lemburg.com
Tue, 02 Apr 2002 11🔞55 +0200

Guido van Rossum wrote:

> Both PyArgGetInt() & PyArgNoArgs() both have comments above them > stating they should not be used. There are no more occurances > of PyArgGetInt(). I'm working on reducing METHOLDARGS, down to 214. > > If you want I can remove them from Include/Python.h when done. Has the api documentation documented them as obsolete? If so, or if they were undocumented, yes, please remove them. If not, I'd see if there's a way to turn these into warnings for one release.

+1 on removing PyArg_GetInt() -1 on removing PyArg_NoArgs() ... this API is still in very active use in third party extensions.

> If so, should I write up anything in NEWS?

Yes, I think so. It's always good to announce explicitly when a previously deprecated item actually gets deleted, no matter how small.

I think we should come up with a better way to deprecate C level APIs. NEWS is not as effective as one might wish; any deprecation or removal of an API should also include upgrade information for the C extension writer so that upgrading their modules does not require diving into the new style C API code every time.

I'd suggest to have a PEP which documents all C API changes or deprecations together with a short decsription of how to update old code.

Another aspect which we ought to consider is that C extension writers may have a different view of when to leave backward compatibility path in favour of a new Python version. IMHO, there should always be a way to emulate old behaviour so that extensions can continue to support Python 1.5.2 if they need to.

-- Marc-Andre Lemburg CEO eGenix.com Software GmbH

Company & Consulting: http://www.egenix.com/ Python Software: http://www.egenix.com/files/python/