bug#42384: octal escape sequences old fashioned

bug#42384: octal escape sequences old fashioned

[積丹尼 Dan Jacobson]

(info "(emacs) Text Display") says:

      The raw bytes with codes ‘U+0080’ (octal 200) through ‘U+009F’ (octal
   237) are displayed as “octal escape sequences”, with the ‘escape-glyph’
   face.  For instance, character code ‘U+0098’ (octal 230) is displayed as
   ‘\230’.  If you change the buffer-local variable ‘ctl-arrow’ to ‘nil’,
   the ASCII control characters are also displayed as octal escape
   sequences instead of caret escape sequences.

OK but octal is rather old fashioned so the user should be given the
choice of hex, etc.

emacs-version "26.3"

bug#42384: octal escape sequences old fashioned

[Robert Pluim]

>>>>> On Thu, 16 Jul 2020 08:50:28 +0800, 積丹尼 Dan Jacobson <jidanni@jidanni.org> said:

    積丹尼> (info "(emacs) Text Display") says:
    積丹尼>       The raw bytes with codes ‘U+0080’ (octal 200) through ‘U+009F’ (octal
    積丹尼>    237) are displayed as “octal escape sequences”, with the ‘escape-glyph’
    積丹尼>    face.  For instance, character code ‘U+0098’ (octal 230) is displayed as
    積丹尼>    ‘\230’.  If you change the buffer-local variable ‘ctl-arrow’ to ‘nil’,
    積丹尼>    the ASCII control characters are also displayed as octal escape
    積丹尼>    sequences instead of caret escape sequences.

    積丹尼> OK but octal is rather old fashioned so the user should be given the
    積丹尼> choice of hex, etc.

    display-raw-bytes-as-hex is a variable defined in `C source code'.
    Its value is t
    Original value was nil

      You can customize this variable.
      This variable was introduced, or its default value was changed, in
      version 26.1 of Emacs.
      Probably introduced at or before Emacs version 26.1.

    Documentation:
    Non-nil means display raw bytes in hexadecimal format.
    The default is to use octal format (200) whereas hexadecimal (x80)
    may be more familiar to users.

(the manual in emacs-27 mentions this)

Robert

bug#42384: octal escape sequences old fashioned

[Eli Zaretskii]

> From: 積丹尼 Dan Jacobson
>  <jidanni@jidanni.org>
> Date: Thu, 16 Jul 2020 08:50:28 +0800
> Cc: rms@gnu.org
> 
> (info "(emacs) Text Display") says:
> 
>       The raw bytes with codes ‘U+0080’ (octal 200) through ‘U+009F’ (octal
>    237) are displayed as “octal escape sequences”, with the ‘escape-glyph’
>    face.  For instance, character code ‘U+0098’ (octal 230) is displayed as
>    ‘\230’.  If you change the buffer-local variable ‘ctl-arrow’ to ‘nil’,
>    the ASCII control characters are also displayed as octal escape
>    sequences instead of caret escape sequences.
> 
> OK but octal is rather old fashioned so the user should be given the
> choice of hex, etc.

We have display-raw-bytes-as-hex for that very reason.

bug#42384: octal escape sequences old fashioned

[積丹尼 Dan Jacobson]

OK Good.
Please be sure display-raw-bytes-as-hex is also mentioned on
(info "(emacs) Text Display")
not only
(info "(emacs) Display Custom")
Thanks!
Maybe it is already in
http://git.savannah.gnu.org/cgit/emacs.git/log/doc/emacs/emacs.texi
but I'm not sure.

bug#42384: octal escape sequences old fashioned

[Eli Zaretskii]

> From: 積丹尼 Dan Jacobson <jidanni@jidanni.org>
> Cc: 42384@debbugs.gnu.org,  rms@gnu.org, rpluim@gmail.com
> Date: Fri, 17 Jul 2020 02:16:01 +0800
> 
> OK Good.
> Please be sure display-raw-bytes-as-hex is also mentioned on
> (info "(emacs) Text Display")

Done.