Blog "about python 3"

[Ned Batchelder]

On 1/4/14 9:17 AM, Chris Angelico wrote:
> On Sun, Jan 5, 2014 at 12:55 AM, Roy Smith <roy at panix.com> wrote:
>> In article <mailman.4882.1388808283.18130.python-list at python.org>,
>>   Mark Lawrence <breamoreboy at yahoo.co.uk> wrote:
>>
>>> Surely everybody prefers fast but incorrect code in
>>> preference to something that is correct but slow?
>>
>> I realize I'm taking this statement out of context, but yes, sometimes
>> fast is more important than correct.  Sometimes the other way around.
>
> More usually, it's sometimes better to be really fast and mostly
> correct than really really slow and entirely correct. That's why we
> use IEEE floating point instead of Decimal most of the time. Though
> I'm glad that Python 3 now deems the default int type to be capable of
> representing arbitrary integers (instead of dropping out to a separate
> long type as Py2 did), I think it's possibly worth optimizing small
> integers to machine words - but mainly, the int type focuses on
> correctness above performance, because the cost is low compared to the
> benefit. With float, the cost of arbitrary precision is extremely
> high, and the benefit much lower.
>
> With Unicode, the cost of perfect support is normally seen to be a
> doubling of internal memory usage (UTF-16 vs UCS-4). Pike and Python
> decided that the cost could, instead, be a tiny measure of complexity
> and actually *less* memory usage (compared to UTF-16, when lots of
> identifiers are ASCII). It's a system that works only when strings are
> immutable, but works beautifully there. Fortunately Pike doesn't have
> any, and Python has only one, idiot like jmf who completely
> misunderstands what's going on and uses microbenchmarks to prove
> obscure points... and then uses nonsense to try to prove... uhh...
> actually I'm not even sure what, sometimes. I wouldn't dare try to
> read his posts except that my mind's already in a rather broken state,
> as a combination of programming and Alice in Wonderland.
>
> ChrisA
>

I really wish we could discuss these things without baiting trolls.

-- 
Ned Batchelder, http://nedbatchelder.com