Why Python 4.0 won't be like Python 3.0

[Steven D'Aprano]

Grant Edwards wrote:

> On 2014-08-17, Mark Lawrence <breamoreboy at yahoo.co.uk> wrote:
>> A blog from Nick Coghlan
>> http://www.curiousefficiency.org/posts/2014/08/python-4000.html that
>> should help put a few minds to rest.
> 
> I agree with the comments that the appellation for "simply the next
> version after 3.9" should be 3.10 and not 4.0.  Everybody I know
> considers SW versions numbers to be dot-separated tuples, not
> floating point numbers.

I consider versions to be *strings*. They include non-numeric components
such as "a", "b", "rc", so they aren't numbers. They're certainly not
floating point numbers, since they have a variable number of decimal
points. Although there is at least one unofficial standard for interpreting
version numbers (semantic versioning), the most popular by far is "whatever
I mean by it today" and the only reasonable interpretation of an arbitrary
software package's version "number" is as free-form text.

Given two version numbers for the same arbitrary package, X and Y, just
about the only thing you can be sure of is that if X < Y, Y is *probably*
newer.

 
> To all of us out here in user-land a change in the first value in the
> version tuple means breakage and incompatibilities.

*All* of us?

So... you're not a user of the Linux kernel?

http://www.linuxplanet.com/news/goodbye-linux-2.6-hello-linux-3.0.html

Or Java 5, 6, 7, 8.

http://en.wikipedia.org/wiki/Java_version_history

Or Firefox.

https://support.mozilla.org/en-US/questions/956361

(I believe that Firefox is now up to version 31, with version 32 due at
3:00pm and 33 due at 5:30pm.)

And not a Mac user either, I imagine, since Mac OS introduces major backward
incompatible changes to point releases. Mac OS version X tends to prefer
version *names* rather than numbers:

http://en.wikipedia.org/wiki/History_of_OS_X

which Debian-based Linux distros also tend to follow.

Or for that matter, not a Python user either:

https://docs.python.org/dev/whatsnew/2.0.html

Version 4.0, when it comes out, will merely be a return to past practices in
Python-land, which are quite similar to practices in many major software
packages. Version 3.0 was the anomaly.



-- 
Steven