Re: RE Module Performance

Newsgroups	comp.lang.python
Date	2013-07-30 07:01 -0700
References	(10 earlier) <mailman.5127.1374808181.3114.python-list@python.org> <8203e802-9dc5-44c5-9547-6e1947ee224b@googlegroups.com> <mailman.5160.1374890711.3114.python-list@python.org> <f4bb2528-930e-4c0a-820e-66f00ac2b5b6@googlegroups.com> <mailman.5188.1374983652.3114.python-list@python.org>
Message-ID	<43ce1b65-9d6d-47dd-b209-9a3bbafc0b8c@googlegroups.com> (permalink)
Subject	Re: RE Module Performance
From	wxjmfauth@gmail.com

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Le dimanche 28 juillet 2013 05:53:22 UTC+2, Ian a écrit :
> On Sat, Jul 27, 2013 at 12:21 PM,  <wxjmfauth@gmail.com> wrote:
> 
> > Back to utf. utfs are not only elements of a unique set of encoded
> 
> > code points. They have an interesting feature. Each "utf chunk"
> 
> > holds intrisically the character (in fact the code point) it is
> 
> > supposed to represent. In utf-32, the obvious case, it is just
> 
> > the code point. In utf-8, that's the first chunk which helps and
> 
> > utf-16 is a mixed case (utf-8 / utf-32). In other words, in an
> 
> > implementation using bytes, for any pointer position it is always
> 
> > possible to find the corresponding encoded code point and from this
> 
> > the corresponding character without any "programmed" information. See
> 
> > my editor example, how to find the char under the caret? In fact,
> 
> > a silly example, how can the caret can be positioned or moved, if
> 
> > the underlying corresponding encoded code point can not be
> 
> > dicerned!
> 
> 
> 
> Yes, given a pointer location into a utf-8 or utf-16 string, it is
> 
> easy to determine the identity of the code point at that location.
> 
> But this is not often a useful operation, save for resynchronization
> 
> in the case that the string data is corrupted.  The caret of an editor
> 
> does not conceptually correspond to a pointer location, but to a
> 
> character index.  Given a particular character index (e.g. 127504), an
> 
> editor must be able to determine the identity and/or the memory
> 
> location of the character at that index, and for UTF-8 and UTF-16
> 
> without an auxiliary data structure that is a O(n) operation.
> 
> 
------

Same conceptual mistake as Steven's example with its buffers,
the buffer does not know it holds characters.
This is not the point to discuss.

-----

I am pretty sure that once you have typed your 127504
ascii characters, you are very happy the buffer of your
editor does not waste time in reencoding the buffer as
soon as you enter an €, the 125505th char. Sorry, I wanted
to say z instead of euro, just to show that backspacing the
last char and reentering a new char implies twice a reencoding.

Somebody wrote "FSR" is just an optimization. Yes, but in case
of an editor à la FSR, this optimization take place everytime you
enter a char. Your poor editor, in fact the FSR, is finally
spending its time in optimizing and finally it optimizes nothing.
(It is even worse).

If you type correctly a z instead of an €, it is not necessary
to reencode the buffer. Problem, you do you know that you do
not have to reencode? simple just check it, and by just checking
it wastes time to test it you have to optimized or not and hurt
a little bit more what is supposed to be an optimization.

Do not confuse the process of optimisation and the result of
optimization (funny, it's like the utf's).

There is a trick to make the editor to know if it has
to be "optimized". Just put some flag somewhere. Then
you fall on the "Houston" syndrome. Houston, we got a
problem, our buffer consumes much more bytes than expected.

>>> sys.getsizeof('€')
40
>>> sys.getsizeof('a')
26

Now the good news. In an editor à la FSR, the
"composition" is not so important. You know,
"practicality beats purity". The hard job
is the text rendering engine and the handling
of the font (even in a raw unicode editor).
And as these tools are luckily not woking à la FSR
(probably because they understand the coding
of the characters), your editor is still working
not so badly.

jmf

Thread

RE Module Performance Devyn Collier Johnson <devyncjohnson@gmail.com> - 2013-07-11 19:44 -0400
  Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-12 02:23 -0700
    Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-12 19:27 +1000
    Re: RE Module Performance Joshua Landau <joshua@landau.ws> - 2013-07-12 10:39 +0100
    Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-12 19:40 +1000
    Re: RE Module Performance Devyn Collier Johnson <devyncjohnson@gmail.com> - 2013-07-12 06:45 -0400
    Re: RE Module Performance Joshua Landau <joshua@landau.ws> - 2013-07-12 16:59 +0100
    Re: RE Module Performance Peter Otten <__peter__@web.de> - 2013-07-12 18:15 +0200
    Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-13 02:21 +1000
    Re: RE Module Performance Devyn Collier Johnson <devyncjohnson@gmail.com> - 2013-07-12 13:58 -0400
      Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-13 05:37 +0000
        Re: RE Module Performance 88888 Dihedral <dihedral88888@gmail.com> - 2013-07-14 11:17 -0700
          Re: RE Module Performance Devyn Collier Johnson <devyncjohnson@gmail.com> - 2013-07-15 06:06 -0400
            Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-15 12:36 +0000
              Dihedral Devyn Collier Johnson <devyncjohnson@gmail.com> - 2013-07-15 08:52 -0400
              Re: Dihedral Joel Goldstick <joel.goldstick@gmail.com> - 2013-07-15 09:03 -0400
              Re: Dihedral Wayne Werner <wayne@waynewerner.com> - 2013-07-15 17:43 -0500
              Re: Dihedral Fábio Santos <fabiosantosart@gmail.com> - 2013-07-15 23:54 +0100
              Re: Dihedral Chris Angelico <rosuav@gmail.com> - 2013-07-16 08:59 +1000
              Re: Dihedral Tim Delaney <timothy.c.delaney@gmail.com> - 2013-07-16 16:06 +1000
              Re: Dihedral Stefan Behnel <stefan_ml@behnel.de> - 2013-07-24 20:08 +0200
              Re: Dihedral Chris Angelico <rosuav@gmail.com> - 2013-07-25 04:23 +1000
              Re: Dihedral Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-07-24 20:15 -0400
    Re: RE Module Performance Tim Delaney <timothy.c.delaney@gmail.com> - 2013-07-13 08:16 +1000
    Re: RE Module Performance Michael Torrie <torriem@gmail.com> - 2013-07-12 17:13 -0600
      Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-24 06:40 -0700
        Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-24 23:48 +1000
        Re: RE Module Performance David Hutto <dwightdhutto@gmail.com> - 2013-07-24 10:17 -0400
        Re: RE Module Performance David Hutto <dwightdhutto@gmail.com> - 2013-07-24 10:19 -0400
        Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-25 00:34 +1000
          Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-25 07:02 +0000
            Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-25 17:39 +1000
        Re: RE Module Performance Michael Torrie <torriem@gmail.com> - 2013-07-24 08:47 -0600
          Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-25 02:27 -0700
            Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-25 20:14 +1000
              Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-25 12:07 -0700
                Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-26 05:18 +1000
                RE: RE Module Performance "Prasad, Ramit" <ramit.prasad@jpmorgan.com> - 2013-07-25 19:30 +0000
                Re: RE Module Performance Michael Torrie <torriem@gmail.com> - 2013-07-25 21:06 -0600
        Re: RE Module Performance Michael Torrie <torriem@gmail.com> - 2013-07-24 09:00 -0600
          Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-25 05:56 +0000
        Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-25 00:56 +1000
        Re: RE Module Performance Terry Reedy <tjreedy@udel.edu> - 2013-07-24 13:52 -0400
        Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-25 04:15 +1000
          Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-25 07:15 +0000
            Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-25 17:58 +1000
              Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-25 09:22 +0000
                Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-25 20:07 +1000
        Re: RE Module Performance Terry Reedy <tjreedy@udel.edu> - 2013-07-24 18:09 -0400
        Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-25 08:19 +1000
        Re: RE Module Performance Michael Torrie <torriem@gmail.com> - 2013-07-24 16:59 -0600
        Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-25 09:24 +1000
        Re: RE Module Performance Serhiy Storchaka <storchaka@gmail.com> - 2013-07-25 08:49 +0300
        Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-25 15:58 +1000
        Re: RE Module Performance Jeremy Sanders <jeremy@jeremysanders.net> - 2013-07-25 14:36 +0100
          Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-25 15:26 +0000
            Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-26 01:36 +1000
              Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-25 17:18 +0000
                Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-26 03:27 +1000
                Re: RE Module Performance Ian Kelly <ian.g.kelly@gmail.com> - 2013-07-25 15:45 -0500
                Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-26 02:48 +0000
                Re: RE Module Performance Ian Kelly <ian.g.kelly@gmail.com> - 2013-07-25 21:20 -0600
                Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-26 06:36 -0700
                Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-26 08:46 -0700
                Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-27 06:28 +0000
                Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-27 03:37 +0000
                Re: RE Module Performance Ian Kelly <ian.g.kelly@gmail.com> - 2013-07-26 22:12 -0600
                Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-27 05:04 +0000
                Re: RE Module Performance Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-07-27 12:13 -0400
                Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-26 06:19 -0700
                Re: RE Module Performance Michael Torrie <torriem@gmail.com> - 2013-07-25 21:09 -0600
                Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-26 06:21 -0700
                Re: RE Module Performance Michael Torrie <torriem@gmail.com> - 2013-07-26 20:05 -0600
                Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-27 11:21 -0700
                Re: RE Module Performance Ian Kelly <ian.g.kelly@gmail.com> - 2013-07-27 21:53 -0600
                Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-28 11:13 -0700
                Re: RE Module Performance MRAB <python@mrabarnett.plus.com> - 2013-07-28 20:04 +0100
                Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-28 12:30 -0700
                Re: RE Module Performance Lele Gaifax <lele@metapensiero.it> - 2013-07-28 22:45 +0200
                Re: RE Module Performance Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-07-28 22:01 +0200
                Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-30 07:01 -0700
                Re: RE Module Performance Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-07-30 16:38 +0200
                Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-30 15:45 +0100
                Re: RE Module Performance MRAB <python@mrabarnett.plus.com> - 2013-07-30 17:13 +0100
                Re: RE Module Performance Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-07-30 18:39 +0200
                Re: RE Module Performance MRAB <python@mrabarnett.plus.com> - 2013-07-30 18:14 +0100
                Re: RE Module Performance Neil Hodgson <nhodgson@iinet.net.au> - 2013-07-31 13:09 +1000
                Re: RE Module Performance Tim Delaney <timothy.c.delaney@gmail.com> - 2013-07-31 03:27 +1000
                Re: RE Module Performance Joshua Landau <joshua@landau.ws> - 2013-07-30 18:40 +0100
                Re: RE Module Performance Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-07-30 20:19 +0200
                Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-30 12:09 -0700
                Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-30 21:04 +0100
                Re: RE Module Performance Michael Torrie <torriem@gmail.com> - 2013-07-30 21:54 -0600
                Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-31 05:45 +0000
                Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-31 08:17 +0100
                Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-31 13:15 -0700
                Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-31 21:41 +0100
                Re: RE Module Performance Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-07-31 10:11 +0200
                Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-31 01:32 -0700
                Re: RE Module Performance Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-07-31 10:59 +0200
                Re: RE Module Performance Michael Torrie <torriem@gmail.com> - 2013-07-31 08:44 -0600
                Re: RE Module Performance Terry Reedy <tjreedy@udel.edu> - 2013-07-30 17:05 -0400
                Re: RE Module Performance Michael Torrie <torriem@gmail.com> - 2013-07-30 21:30 -0600
                Re: RE Module Performance Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-07-31 09:23 +0200
                Re: RE Module Performance Michael Torrie <torriem@gmail.com> - 2013-07-31 08:27 -0600
                Re: RE Module Performance Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-07-28 10:45 +0200
                FSR and unicode compliance - was Re: RE Module Performance Michael Torrie <torriem@gmail.com> - 2013-07-28 09:52 -0600
                Re: FSR and unicode compliance - was Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-28 12:23 -0700
                Re: FSR and unicode compliance - was Re: RE Module Performance MRAB <python@mrabarnett.plus.com> - 2013-07-28 20:44 +0100
                Re: FSR and unicode compliance - was Re: RE Module Performance Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-07-28 21:55 +0200
                Re: FSR and unicode compliance - was Re: RE Module Performance Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-07-28 20:52 +0000
                Re: FSR and unicode compliance - was Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-29 04:43 -0700
                Re: FSR and unicode compliance - was Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-29 12:57 +0100
                Re: FSR and unicode compliance - was Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-29 05:56 -0700
                Re: FSR and unicode compliance - was Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-29 07:20 -0700
                Re: FSR and unicode compliance - was Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-29 15:49 +0100
                Re: FSR and unicode compliance - was Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-29 09:31 -0700
                Re: FSR and unicode compliance - was Re: RE Module Performance Heiko Wundram <modelnine@modelnine.org> - 2013-07-29 14:06 +0200
                Re: FSR and unicode compliance - was Re: RE Module Performance Devyn Collier Johnson <devyncjohnson@gmail.com> - 2013-07-29 08:43 -0400
                Re: FSR and unicode compliance - was Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-28 18:03 +0100
                Re: FSR and unicode compliance - was Re: RE Module Performance Terry Reedy <tjreedy@udel.edu> - 2013-07-28 13:36 -0400
                Re: FSR and unicode compliance - was Re: RE Module Performance wxjmfauth@gmail.com - 2013-07-29 06:36 -0700
                Re: FSR and unicode compliance - was Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-28 19:03 +0100
                Re: RE Module Performance Joshua Landau <joshua@landau.ws> - 2013-07-28 19:19 +0100
                Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-28 19:29 +0100
                Re: RE Module Performance Terry Reedy <tjreedy@udel.edu> - 2013-07-28 15:06 -0400
                Re: RE Module Performance Joshua Landau <joshua@landau.ws> - 2013-07-28 23:14 +0100
                Re: RE Module Performance Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-07-28 20:51 +0200
                Re: RE Module Performance Chris Angelico <rosuav@gmail.com> - 2013-07-29 00:07 +0100
                Re: RE Module Performance Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-07-26 22:38 +0200
        Re: RE Module Performance Devyn Collier Johnson <devyncjohnson@gmail.com> - 2013-07-25 09:44 -0400
        Re: RE Module Performance Ian Kelly <ian.g.kelly@gmail.com> - 2013-07-25 15:53 -0500
    Re: RE Module Performance MRAB <python@mrabarnett.plus.com> - 2013-07-13 00:16 +0100
    Re: RE Module Performance Tim Delaney <timothy.c.delaney@gmail.com> - 2013-07-14 05:34 +1000
    Re: RE Module Performance Devyn Collier Johnson <devyncjohnson@gmail.com> - 2013-07-16 06:30 -0400
      Re: RE Module Performance 88888 Dihedral <dihedral88888@gmail.com> - 2013-07-18 13:17 -0700

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