[Python-Dev] Optimization of the Year

[Raymond Hettinger]

[GvR]
> I disagree with making the hack of setting list->allocated = -1 an
> official part of the list object API.

Okay.


> Since you have ignored repeated requests for real-life examples of
> code that messes with ob_item outside the core, 

Haven't found any.  Initially, I thought there were because the guard
was getting tripped.  Now, it looks like Hye-Shik's NULL check is
sufficient.


> let's keep the
> 'allocated' field an internal detail of the list implementation.

Yes.


>  Then
> I can ignore the other posts about binary (in)compatibility too. :-)

Right.


[Armin]
> BUT there is something that the patch does wrong: it never reclaims
memory
> from the list, unlike the NRESIZE trick which used to realloc with a
> smaller
> size occasionally.

Yes.  I had already caught that and sent in a change to Hye-Shik to make
sure downward resizing can happen.  Also, I'll incorporate the minor
fixups you sent in.  Any further adventures should probably be done as a

separate patch (don't change too many things at once).



Raymond