Re: ASCII and Unicode [was Re: Managing Google Groups headaches]

References	(3 earlier) <roy-9C2ADB.19585404122013@news.panix.com> <51007240-6bc9-4f0b-9937-4883bcc0ceb6@googlegroups.com> <roy-1384C7.02363006122013@news.panix.com> <ae4b6a4d-fbd4-4d10-a860-9589e6045d16@googlegroups.com> <52a21ec1$0$30003$c3e8da3$5496439d@news.astraweb.com>
Date	2013-12-07 10:42 +1100
Subject	Re: ASCII and Unicode [was Re: Managing Google Groups headaches]
From	Chris Angelico <rosuav@gmail.com>
Newsgroups	comp.lang.python
Message-ID	<mailman.3673.1386373692.18130.python-list@python.org> (permalink)

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On Sat, Dec 7, 2013 at 6:00 AM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
>     - character 33 was permitted to be either the exclamation
>       mark ! or the logical OR symbol |
>
>     - consequently character 124 (vertical bar) was always
>       displayed as a broken bar ¦, which explains why even today
>       many keyboards show it that way
>
>     - character 35 was permitted to be either the number sign # or
>       the pound sign £
>
>     - character 94 could be either a caret ^ or a logical NOT ¬

Yeah, good fun stuff. I first met several of these ambiguities in the
OS/2 REXX documentation, which detailed the language's operators by
specifying their byte values as well as their characters - for
instance, this quote from the docs (yeah, I still have it all here):

"""
Note:   Depending upon your Personal System keyboard and the code page
you are using, you may not have the solid vertical bar to select. For
this reason, REXX also recognizes the use of the split vertical bar as
a logical OR symbol. Some keyboards may have both characters. If so,
they are not interchangeable; only the character that is equal to the
ASCII value of 124 works as the logical OR. This type of mismatch can
also cause the character on your screen to be different from the
character on your keyboard.
"""
(The front material on the docs says "(C) Copyright IBM Corp. 1987,
1994. All Rights Reserved.")

It says "ASCII value" where on this list we would be more likely to
call it "byte value", and I'd prefer to say "represented by" rather
than "equal to", but nonetheless, this is still clearly distinguishing
characters and bytes. The language spec is on characters, but
ultimately the interpreter is going to be looking at bytes, so when
there's a problem, it's byte 124 that's the one defined as logical OR.
Oh, and note the copyright date. The byte/char distinction isn't new.

ChrisA

Thread

Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-11-28 05:52 -0800
  Re: Managing Google Groups headaches Chris Angelico <rosuav@gmail.com> - 2013-11-29 00:58 +1100
    Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-11-28 06:17 -0800
      Re: Managing Google Groups headaches Chris Angelico <rosuav@gmail.com> - 2013-11-29 01:25 +1100
        Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-11-28 07:04 -0800
          Re: Managing Google Groups headaches Chris Angelico <rosuav@gmail.com> - 2013-11-29 02:08 +1100
            Re: Managing Google Groups headaches Alister <alister.ware@ntlworld.com> - 2013-11-28 15:50 +0000
              Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-11-28 08:22 -0800
                Re: Managing Google Groups headaches Alister <alister.ware@ntlworld.com> - 2013-11-28 16:33 +0000
            Re: Managing Google Groups headaches Alister <alister.ware@ntlworld.com> - 2013-11-28 15:49 +0000
            Re: Managing Google Groups headaches Alister <alister.ware@ntlworld.com> - 2013-11-28 15:49 +0000
            Re: Managing Google Groups headaches Alister <alister.ware@ntlworld.com> - 2013-11-28 15:50 +0000
              Re: Managing Google Groups headaches Roy Smith <roy@panix.com> - 2013-11-28 11:43 -0500
                Re: Managing Google Groups headaches Chris Angelico <rosuav@gmail.com> - 2013-11-29 04:29 +1100
                Re: Managing Google Groups headaches Neil Cerutti <neilc@norwich.edu> - 2013-12-02 13:03 +0000
                Re: Managing Google Groups headaches Roy Smith <roy@panix.com> - 2013-12-02 08:29 -0500
                Re: Managing Google Groups headaches Neil Cerutti <neilc@norwich.edu> - 2013-12-02 14:04 +0000
                Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-12-02 09:11 -0800
                Re: Managing Google Groups headaches Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-12-02 17:48 +0000
                Re: Managing Google Groups headaches Chris Angelico <rosuav@gmail.com> - 2013-12-03 04:54 +1100
                Re: Managing Google Groups headaches Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-12-02 18:07 +0000
                Re: Managing Google Groups headaches Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-12-02 19:56 -0500
                Re: Managing Google Groups headaches Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-12-02 19:54 -0500
                Re: [OT] Managing Google Groups headaches Michael Torrie <torriem@gmail.com> - 2013-12-02 18:17 -0700
                Re: [OT] Managing Google Groups headaches Roy Smith <roy@panix.com> - 2013-12-02 20:43 -0500
                Re: [OT] Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-12-02 18:27 -0800
                Re: [OT] Managing Google Groups headaches Michael Torrie <torriem@gmail.com> - 2013-12-02 20:09 -0700
                Re: [OT] Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-12-02 19:26 -0800
                Re: [OT] Managing Google Groups headaches Grant Edwards <invalid@invalid.invalid> - 2013-12-03 04:27 +0000
                Re: [OT] Managing Google Groups headaches Chris Angelico <rosuav@gmail.com> - 2013-12-03 18:01 +1100
                Re: [OT] Managing Google Groups headaches alex23 <wuwei23@gmail.com> - 2013-12-03 16:30 +1000
                Re: [OT] Managing Google Groups headaches Steven D'Aprano <steve@pearwood.info> - 2013-12-03 07:13 +0000
                Re: [OT] Managing Google Groups headaches alex23 <wuwei23@gmail.com> - 2013-12-04 10:23 +1000
                Re: [OT] Managing Google Groups headaches Neil Cerutti <neilc@norwich.edu> - 2013-12-04 14:34 +0000
                Re: [OT] Managing Google Groups headaches Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-12-04 15:21 +0000
                Re: [OT] Managing Google Groups headaches Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-12-03 12:09 +0000
          Re: Managing Google Groups headaches Michael Torrie <torriem@gmail.com> - 2013-11-28 08:40 -0700
          Re: Managing Google Groups headaches Travis Griggs <travisgriggs@gmail.com> - 2013-11-28 08:23 -0800
          Re: Managing Google Groups headaches Ned Batchelder <ned@nedbatchelder.com> - 2013-11-28 12:23 -0500
          Re: Managing Google Groups headaches Michael Torrie <torriem@gmail.com> - 2013-11-28 11:29 -0700
            Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-11-28 10:37 -0800
              Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-11-28 11:00 -0800
                Re: Managing Google Groups headaches Michael Torrie <torriem@gmail.com> - 2013-11-28 12:55 -0700
              Re: Managing Google Groups headaches Walter Hurry <walterhurry@lavabit.com> - 2013-11-28 19:40 +0000
              Re: Managing Google Groups headaches Michael Torrie <torriem@gmail.com> - 2013-11-28 11:50 -0700
                Re: Managing Google Groups headaches Arif Khokar <akhokar1234@wvu.edu> - 2013-11-28 19:46 -0500
                Re: Managing Google Groups headaches Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-11-29 14:41 +0000
                Re: Managing Google Groups headaches Grant Edwards <invalid@invalid.invalid> - 2013-11-29 16:17 +0000
                Re: Managing Google Groups headaches Cameron Simpson <cs@zip.com.au> - 2013-12-04 11:38 +1100
                Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-12-03 17:39 -0800
                Re: Managing Google Groups headaches Chris Angelico <rosuav@gmail.com> - 2013-12-04 13:03 +1100
                Re: Managing Google Groups headaches Cameron Simpson <cs@zip.com.au> - 2013-12-05 09:47 +1100
                Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-12-05 23:42 -0800
              Re: Managing Google Groups headaches Walter Hurry <walterhurry@lavabit.com> - 2013-11-28 20:39 +0000
          Re: Managing Google Groups headaches Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-11-28 16:41 -0500
            Re: Managing Google Groups headaches pecore@pascolo.net - 2013-11-30 14:25 +0100
              Re: Managing Google Groups headaches Cameron Simpson <cs@zip.com.au> - 2013-12-04 11:40 +1100
                Re: Managing Google Groups headaches Grant Edwards <invalid@invalid.invalid> - 2013-12-04 15:50 +0000
                Re: Managing Google Groups headaches Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-12-04 16:07 +0000
                Re: Managing Google Groups headaches Ned Batchelder <ned@nedbatchelder.com> - 2013-12-04 11:21 -0500
                Re: Managing Google Groups headaches Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-12-04 16:33 +0000
          Re: Managing Google Groups headaches Zero Piraeus <z@etiol.net> - 2013-11-28 13:29 -0300
            Re: Managing Google Groups headaches Grant Edwards <invalid@invalid.invalid> - 2013-11-29 16:15 +0000
          Re: Managing Google Groups headaches Terry Reedy <tjreedy@udel.edu> - 2013-11-28 17:32 -0500
          Re: Managing Google Groups headaches Terry Reedy <tjreedy@udel.edu> - 2013-11-28 17:44 -0500
          Re: Managing Google Groups headaches Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-11-29 14:39 +0000
  Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-11-28 10:13 -0800
    Re: Managing Google Groups headaches Rich Kulawiec <rsk@gsp.org> - 2013-12-04 09:52 -0500
      Re: Managing Google Groups headaches Roy Smith <roy@panix.com> - 2013-12-04 19:58 -0500
        Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-12-05 23:13 -0800
          Re: Managing Google Groups headaches Roy Smith <roy@panix.com> - 2013-12-06 02:36 -0500
            Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-12-06 05:03 -0800
              Re: Managing Google Groups headaches Chris Angelico <rosuav@gmail.com> - 2013-12-07 00:19 +1100
                Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-12-06 05:32 -0800
                Re: Managing Google Groups headaches Chris Angelico <rosuav@gmail.com> - 2013-12-07 00:48 +1100
                Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-12-06 06:11 -0800
                Re: Managing Google Groups headaches Chris Angelico <rosuav@gmail.com> - 2013-12-07 01:51 +1100
              ASCII and Unicode [was Re: Managing Google Groups headaches] Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-12-06 19:00 +0000
                Re: ASCII and Unicode [was Re: Managing Google Groups headaches] Gene Heskett <gheskett@wdtv.com> - 2013-12-06 14:34 -0500
                Re: ASCII and Unicode [was Re: Managing Google Groups headaches] Roy Smith <roy@panix.com> - 2013-12-06 20:54 +0000
                Re: ASCII and Unicode [was Re: Managing Google Groups headaches] Chris Angelico <rosuav@gmail.com> - 2013-12-07 10:42 +1100
                Re: ASCII and Unicode [was Re: Managing Google Groups headaches] rusi <rustompmody@gmail.com> - 2013-12-06 18:33 -0800
                Re: ASCII and Unicode [was Re: Managing Google Groups headaches] Chris Angelico <rosuav@gmail.com> - 2013-12-07 13:41 +1100
                Re: ASCII and Unicode [was Re: Managing Google Groups headaches] rusi <rustompmody@gmail.com> - 2013-12-06 19:16 -0800
                Re: ASCII and Unicode [was Re: Managing Google Groups headaches] Chris Angelico <rosuav@gmail.com> - 2013-12-07 15:08 +1100
                Re: ASCII and Unicode [was Re: Managing Google Groups headaches] MRAB <python@mrabarnett.plus.com> - 2013-12-07 03:19 +0000
                Re: ASCII and Unicode giacomo boffi <pecore@pascolo.net> - 2013-12-07 17:05 +0100
                Re: ASCII and Unicode rusi <rustompmody@gmail.com> - 2013-12-08 08:41 -0800
                Re: ASCII and Unicode Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-12-08 17:22 +0000
                Re: ASCII and Unicode rusi <rustompmody@gmail.com> - 2013-12-08 09:39 -0800
                Re: ASCII and Unicode giacomo boffi <pecore@pascolo.net> - 2013-12-08 21:11 +0100
                Re: ASCII and Unicode rusi <rustompmody@gmail.com> - 2013-12-08 19:02 -0800
              Re: Managing Google Groups headaches Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2013-12-07 12:27 +1300
              Re: Managing Google Groups headaches Ned Batchelder <ned@nedbatchelder.com> - 2013-12-06 21:24 -0500
                Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-12-06 23:43 -0800
                Re: Managing Google Groups headaches wxjmfauth@gmail.com - 2013-12-07 02:16 -0800
                Re: Managing Google Groups headaches Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-12-07 11:25 +0000
                Re: Managing Google Groups headaches Chris Angelico <rosuav@gmail.com> - 2013-12-07 22:49 +1100
                Re: Managing Google Groups headaches Roy Smith <roy@panix.com> - 2013-12-07 11:08 -0500
                Re: Managing Google Groups headaches Rotwang <sg552@hotmail.co.uk> - 2013-12-07 16:15 +0000
                Re: Managing Google Groups headaches Tim Chase <python.list@tim.thechases.com> - 2013-12-07 10:19 -0600
                Re: Managing Google Groups headaches rusi <rustompmody@gmail.com> - 2013-12-07 08:27 -0800
                Re: Managing Google Groups headaches Ned Batchelder <ned@nedbatchelder.com> - 2013-12-07 12:04 -0500
          Re: Managing Google Groups headaches Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-12-07 03:07 +0000
            Re: Managing Google Groups headaches Roy Smith <roy@panix.com> - 2013-12-06 22:40 -0500
    Re: Managing Google Groups headaches Chris Angelico <rosuav@gmail.com> - 2013-12-05 02:46 +1100
    Re: Managing Google Groups headaches Travis Griggs <travisgriggs@gmail.com> - 2013-12-04 08:31 -0800

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