Coding style and Python versions (was Re: Another itertool function?)

[Alex Martelli]

Aahz wrote:

> In article <b8hc64$6n2$1 at slb9.atl.mindspring.net>,
> Andrew Dalke <adalke at mindspring.com> wrote:
>>
>>        i = i + 1
> 
> I'm a little curious why you didn't write this as
> 
>     i += 1
> 
> Any reason (i.e. still need to support 1.5.2) or just habit?  If the
> latter, why haven't you changed your habit?

There is no special reason to "change that habit", e.g. not performance:

[alex at lancelot src]$ python Lib/timeit.py 'i=0; i+=1'
1000000 loops, best of 3: 0.284 usec per loop
[alex at lancelot src]$ python Lib/timeit.py 'i=0; i=i+1'
1000000 loops, best of 3: 0.281 usec per loop
[alex at lancelot src]$ python Lib/timeit.py 'i=0; i=i+1'
1000000 loops, best of 3: 0.281 usec per loop
[alex at lancelot src]$ python Lib/timeit.py 'i=0; i=i+1'
1000000 loops, best of 3: 0.284 usec per loop
[alex at lancelot src]$ python Lib/timeit.py 'i=0; i+=1'
1000000 loops, best of 3: 0.282 usec per loop
[alex at lancelot src]$ python Lib/timeit.py 'i=0; i+=1'
1000000 loops, best of 3: 0.278 usec per loop

No statistically significant / measurable difference.  The tiny difference
in conciseness is hardly compelling one way or another, either.


Alex