[Python-Dev] #Python3 ! ? (was Python Library Support in 3.x)

[Terry Reedy]

On 6/20/2010 5:53 PM, Nick Coghlan wrote:
> On Mon, Jun 21, 2010 at 7:12 AM, Simon de Vlieger<simon at ikanobori.jp>  wrote:
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>> In reply to the recent post by Laurens and the vow I made to change the text
>> which is presented on the python-commandments domain I have asked Laurens to
>> write a new text on the subject.

> That's a fairly decent write-up in my opinion. As Laurens pointed, it
> trends towards the "use Python 3 if you can, Python 2 if you need to"
> point of view, which I personally think is the right spin to be
> putting on this issue, but obviously opinions will vary on that front.
>
> About the only specific wording tweak I would suggest is that "little
> regard for backwards compatibility" should be phrased as "less regard
> for backwards compatibility". There were still quite a few ideas we
> rejected as gratuitously incompatible, even for Py3k (the eventual
> decision to retain old-style string formatting comes to mind).

I have much the same opinion, and the ame suggestion, as Nick. People do 
not usually see the proposals that were rejected and the changes not 
made in 3.0. For those who *do* wish, there are about 25 items listed at

http://www.python.org/dev/peps/pep-3099/
Things that will Not Change in Python 3000

Nick listed one thing not on the list. Eliminating the duplicate method 
names in the unittest module is another. (In isolation, most everyone 
was in favor. Guido's reason for leaving the duplication: porting 2 to 3 
is much easier with a good (and stable) test suite. Therefore, cleaning 
up unittest and possibly breaking test suites, even with a 2to3 
conversion, would not be a good idea.)

Terry Jan Reedy