[Python-Dev] PEP 3003 - Python Language Moratorium

[Terry Reedy]

Brett Cannon wrote:
> On Fri, Nov 6, 2009 at 08:02, Guido van Rossum <guido at python.org> wrote:
>> On Thu, Nov 5, 2009 at 9:55 PM, Brett Cannon <brett at python.org> wrote:
>>> The clarification I need is will this in any way influence when
>>> modules are removed. If they stay in for the life of a major version
>>> then I want it made clear that bug fixes for the code take lower
>>> priority over all other code in the standard library.
>> I think we should be as cautious as ever with removing modules. We've
>> had our chance for clean-up without abandon with Py3k; now we should
>> stick with our commitment to backwards compatibility. In fact, we
>> should probably be *more* conservative than we already were given that
>> the amount of code written in Python is always increasing and hence
>> the cumulative pain caused by incompatible changes will increase too.
>>
>> I'm fine with silent deprecations or requiring a flag to turn on
>> deprecation warnings (like Java does).
>>
> 
> We can discuss this on the stdlib-sig and come back with a proposal on
> how to update PEP 4 with an explicit policy on how to handle
> deprecations (either Nick's proposal or some flag, and then how long
> to let the deprecation last, i.e. three versions or the life of a
> major version of Python).

Complete removal of modules during the seems to have caused problems 
especially for people supporting a range of versions. On the other hand, 
you want to be able to replace and cease support of modules. So rather 
that complete removal, perhaps move them to a new package called, for 
instance, 'old'. And move their doc sections to a new chapter call 'Old 
Modules' which would begin with something like "The following modules 
have been replaced but are still present in the *old* package for back 
compatibility. They are no longer maintained and will possibly disappear 
in the future, such as if there is ever a Python4." This suggestion 
based on the "3. Non-essential Built-in Functions" of the 2.x doc, whose 
contents disappeared in 3.0 (even though that seems not to have been 
specified in the doc).

Terry Jan Reedy