[Python-Dev] PEP 407 / splitting the stdlib

[Antoine Pitrou]

On Thu, 19 Jan 2012 11:03:15 +1000
Nick Coghlan <ncoghlan at gmail.com> wrote:
> 
> 1. I believe the PEP currently proposes just taking the "no more than
> 9" limit off the minor version of the language. Feature releases would
> just come out every 6 months, with every 4th release flagged as a
> language release.

With the moratorium suggestion factored in, yes. The PEP insists on
support duration rather than the breadth of changes, though. I think
that's a more important piece of information for users.

(you don't care whether or not new language constructs were added, if
you were not planning to use them)

> I don't like this scheme because it tries to use one number (the minor
> version field) to cover two very different concepts (stdlib updates
> and language updates). While technically feasible, this is
> unnecessarily obscure and confusing for end users.

As an end user I wouldn't really care whether a release is "stdlib
changes only" or "language/builtins additions too" (especially in a
language like Python where the boundaries are somewhat blurry). I think
this distinction is useful mainly for experts and therefore not worth
complicating version numbering for.

> 2. Brett's alternative proposal is that we switch to using the major
> version for language releases and the minor version for stdlib
> releases. We would then release 3.3, 3.4, 3.5 and 3.6 at 6 month
> intervals, with 4.0 then being released in August 2014 as a new
> language version.

The main problem I see with this is that Python 3 was a big
disruptive event for the community, and calling a new version "Python
4" may make people anxious at the prospect of compatibility breakage.
Instead of spending some time advertising that "Python 4" is a safe
upgrade, perhaps we could simply call it "Python 3.X+1"?

(and, as you point out, keep "Python X+1" for when we want to change the
language in incompatible ways again)

> So in August this year, we would release 3.3+12.08, followed by
> 3.3+13.02, 3.3+13.08, 3.3+14.02 at 6 month intervals, and then the
> next language release as 3.4+14.08. If someone refers to just Python
> 3.3, then the "at least stdlib 12.08" is implied. If they refer to
> Python stdlib 12.08, 13.02, 13.08 or 14.02, then it is the dependency
> on "Python 3.3" that is implied.

If I were a casual user of a piece of software, I'd really find such a
numbering scheme complicated and intimidating. I don't think most users
want such a level of information.

Regards

Antoine.