[Numpy-discussion] Created NumPy 1.7.x branch

[Travis Oliphant]

On Jun 25, 2012, at 10:35 PM, David Cournapeau wrote:

> On Tue, Jun 26, 2012 at 4:10 AM, Ondřej Čertík <ondrej.certik at gmail.com> wrote:
> 
>> 
>> My understanding is that Travis is simply trying to stress "We have to
>> think about the implications of our changes on existing users." and
>> also that little changes (with the best intentions!) that however mean
>> either a breakage or confusion for users (due to historical reasons)
>> should be avoided if possible. And I very strongly feel the same way.
>> And I think that most people on this list do as well.
> 
> I think Travis is more concerned about API than ABI changes (in that
> example for 1.4, the ABI breakage was caused by a change that was
> pushed by Travis IIRC).

In the present climate, I'm going to have to provide additional context to a comment like this.  This is not an accurate enough characterization of events.   I was trying to get date-time changes in, for sure.   I generally like feature additions to NumPy.   (Robert Kern was also involved with that effort and it was funded by an active user of NumPy.    I was concerned that the changes would break the ABI.  In fact, I expected them to --- I was not against such changes, even though it was a change in previously discussed policy.  We just needed to advertise them widely.       Other voices, prevailed, however, and someone else believed the changes would not break ABI compatibility.   Unfortunately, I did not have much time to look into the matter as I was working full time on other things.    

If I had had my way we would have released NumPy 1.5 at the time and widely advertised the ABI breakage (and moved at the same time to a design that would have made it easier to upgrade without breaking the ABI).    I do not believe it would have been that big of a deal as long as we communicated correctly about the release.     I still don't think it's correct to be overly concerned about ABI breakage in a world where packages can just be re-compiled against the new version in a matter of minutes with one hand and with the other make changes to the code base that change existing code behavior.    I think the fact that the latter has occurred is evidence that we have to sacrifice one of them.   And ABI compatibility is the preferred one to sacrifice by a long stretch in my view. 

-Travis