Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.python > #41204

Re: String performance regression from python 3.2 to 3.3

Show key headers only | View raw

On Thu, Mar 14, 2013 at 11:52 AM, MRAB <python@mrabarnett.plus.com> wrote:
> On 13/03/2013 23:43, Chris Angelico wrote:
>>
>> On Thu, Mar 14, 2013 at 3:49 AM, rusi <rustompmody@gmail.com> wrote:
>>>
>>> On Mar 13, 3:59 pm, Chris Angelico <ros...@gmail.com> wrote:
>>>>
>>>> On Wed, Mar 13, 2013 at 9:11 PM, rusi <rustompm...@gmail.com> wrote:
>>>> > Uhhh..
>>>> > Making the subject line useful for all readers
>>>>
>>>> I should have read this one before replying in the other thread.
>>>>
>>>> jmf, I'd like to see evidence that there has been a performance
>>>> regression compared against a wide build of Python 3.2. You still have
>>>> never answered this fundamental, that the narrow builds of Python are
>>>> *BUGGY* in the same way that JavaScript/ECMAScript is. And believe you
>>>> me, the utterly unnecessary hassles I have had to deal with when
>>>> permitting user-provided .js code to script my engine have wasted
>>>> rather more dev hours than you would believe - there are rather a lot
>>>> of stupid edge cases to deal with.
>>>
>>>
>>> This assumes that there are only three choices:
>>> - narrow build that is buggy (surrogate pairs for astral characters)
>>> - wide build that is 4-fold space inefficient for wide variety of
>>> common (ASCII) use-cases
>>> - flexible string engine that chooses a small tradeoff of space
>>> efficiency over time efficiency.
>>>
>>> There is a fourth choice: narrow build that chooses to be partial over
>>> being buggy. ie when an astral character is encountered, an exception
>>> is thrown rather than trying to fudge it into a 16-bit
>>> representation.
>>
>>
>> As a simple factual matter, narrow builds of Python 3.2 don't do that.
>> So it doesn't factor into my original statement. But if you're talking
>> about a proposal for 3.4, then sure, that's a theoretical possibility.
>> It wouldn't be "buggy" in the sense of "string indexing/slicing
>> unexpectedly does the wrong thing", but it would still be incomplete
>> Unicode support, and I don't think people would appreciate it. Much
>> better to have graceful degradation: if there are non-BMP characters
>> in the string, then instead of throwing an exception, it just makes
>> the string wider.
>>
> [snip]
> Do you mean that instead of switching between 1/2/4 bytes per codepoint
> it would switch between 2/4 bytes per codepoint?

That's my point. We already have the better version. :)

ChrisA

Back to comp.lang.python | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

A reply for rusi (FSR) jmfauth <wxjmfauth@gmail.com> - 2013-03-13 02:36 -0700
  Re: A reply for rusi (FSR) rusi <rustompmody@gmail.com> - 2013-03-13 03:07 -0700
    String performance regression from python 3.2 to 3.3 rusi <rustompmody@gmail.com> - 2013-03-13 03:11 -0700
      Re: String performance regression from python 3.2 to 3.3 Chris Angelico <rosuav@gmail.com> - 2013-03-13 21:59 +1100
        Re: String performance regression from python 3.2 to 3.3 rusi <rustompmody@gmail.com> - 2013-03-13 09:49 -0700
          Re: String performance regression from python 3.2 to 3.3 Chris Angelico <rosuav@gmail.com> - 2013-03-14 10:43 +1100
          Re: String performance regression from python 3.2 to 3.3 MRAB <python@mrabarnett.plus.com> - 2013-03-14 00:52 +0000
          Re: String performance regression from python 3.2 to 3.3 Chris Angelico <rosuav@gmail.com> - 2013-03-14 11:55 +1100
          Re: String performance regression from python 3.2 to 3.3 MRAB <python@mrabarnett.plus.com> - 2013-03-14 02:01 +0000
            Re: String performance regression from python 3.2 to 3.3 Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-03-14 04:05 +0000
              Re: String performance regression from python 3.2 to 3.3 Chris Angelico <rosuav@gmail.com> - 2013-03-14 17:47 +1100
                Re: String performance regression from python 3.2 to 3.3 rusi <rustompmody@gmail.com> - 2013-03-14 03:48 -0700
                Re: String performance regression from python 3.2 to 3.3 Terry Reedy <tjreedy@udel.edu> - 2013-03-14 19:14 -0400
                Re: String performance regression from python 3.2 to 3.3 Terry Reedy <tjreedy@udel.edu> - 2013-03-14 20:48 -0400
                Re: String performance regression from python 3.2 to 3.3 rusi <rustompmody@gmail.com> - 2013-03-15 10:07 -0700
                RE: String performance regression from python 3.2 to 3.3 Andriy Kornatskyy <andriy.kornatskyy@live.com> - 2013-03-15 21:04 +0300
          Re: String performance regression from python 3.2 to 3.3 Terry Reedy <tjreedy@udel.edu> - 2013-03-13 22:35 -0400
          Re: String performance regression from python 3.2 to 3.3 Chris Angelico <rosuav@gmail.com> - 2013-03-14 17:21 +1100
        Re: String performance regression from python 3.2 to 3.3 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-03-13 18:42 +0100
          Re: String performance regression from python 3.2 to 3.3 Chris Angelico <rosuav@gmail.com> - 2013-03-14 11:19 +1100
            Re: String performance regression from python 3.2 to 3.3 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-03-16 03:44 +0100
              Re: String performance regression from python 3.2 to 3.3 Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-03-16 03:56 +0000
                Re: String performance regression from python 3.2 to 3.3 rusi <rustompmody@gmail.com> - 2013-03-15 21:26 -0700
                Re: String performance regression from python 3.2 to 3.3 Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-03-16 08:47 +0000
                Re: String performance regression from python 3.2 to 3.3 Neil Hodgson <nhodgson@iinet.net.au> - 2013-03-17 09:00 +1100
                Re: String performance regression from python 3.2 to 3.3 Roy Smith <roy@panix.com> - 2013-03-16 18:10 -0400
              Re: String performance regression from python 3.2 to 3.3 Chris Angelico <rosuav@gmail.com> - 2013-03-16 14:59 +1100
                Re: String performance regression from python 3.2 to 3.3 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-03-16 05:12 +0100
                Re: String performance regression from python 3.2 to 3.3 Chris Angelico <rosuav@gmail.com> - 2013-03-16 15:20 +1100
                Re: String performance regression from python 3.2 to 3.3 rusi <rustompmody@gmail.com> - 2013-03-15 22:21 -0700
              Re: String performance regression from python 3.2 to 3.3 Chris Angelico <rosuav@gmail.com> - 2013-03-16 15:09 +1100
                Re: String performance regression from python 3.2 to 3.3 rusi <rustompmody@gmail.com> - 2013-03-15 21:35 -0700
                Re: String performance regression from python 3.2 to 3.3 Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-03-16 04:56 +0000
                Re: String performance regression from python 3.2 to 3.3 Terry Reedy <tjreedy@udel.edu> - 2013-03-16 01:05 -0400
                Re: String performance regression from python 3.2 to 3.3 Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-03-16 05:38 +0000
                Re: String performance regression from python 3.2 to 3.3 Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-03-16 05:25 +0000
                Re: String performance regression from python 3.2 to 3.3 Roy Smith <roy@panix.com> - 2013-03-16 09:29 -0400
                Re: String performance regression from python 3.2 to 3.3 rusi <rustompmody@gmail.com> - 2013-03-16 09:39 -0700
                Re: String performance regression from python 3.2 to 3.3 Roy Smith <roy@panix.com> - 2013-03-16 14:00 -0400
                Re: String performance regression from python 3.2 to 3.3 jmfauth <wxjmfauth@gmail.com> - 2013-03-16 13:42 -0700
  Re: A reply for rusi (FSR) Chris Angelico <rosuav@gmail.com> - 2013-03-13 21:32 +1100

csiph-web