bug#11263: 23.4; shell-script: << does not always mean here-document

bug#11263: 23.4; shell-script: << does not always mean here-document

[Vincent Lefevre]

When I type << in shell-script mode, Emacs thinks this begins a
here-document. This is not always the case, e.g. in the following
lines:

foo='bar<<'
echo "${foo%<<}"
echo $((1<<8))

And specifically for zsh:

echo $[1<<8]


In GNU Emacs 23.4.1 (x86_64-pc-linux-gnu, GTK+ Version 2.24.10)
 of 2012-04-07 on trouble, modified by Debian
Windowing system distributor `The X.Org Foundation', version 11.0.11104000
configured using `configure  '--build' 'x86_64-linux-gnu' '--build' 'x86_64-linux-gnu' '--prefix=/usr' '--sharedstatedir=/var/lib' '--libexecdir=/usr/lib' '--localstatedir=/var/lib' '--infodir=/usr/share/info' '--mandir=/usr/share/man' '--with-pop=yes' '--enable-locallisppath=/etc/emacs23:/etc/emacs:/usr/local/share/emacs/23.4/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/23.4/site-lisp:/usr/share/emacs/site-lisp' '--with-crt-dir=/usr/lib/x86_64-linux-gnu' '--with-x=yes' '--with-x-toolkit=gtk' '--with-toolkit-scroll-bars' 'build_alias=x86_64-linux-gnu' 'CFLAGS=-g -O2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Wformat-security -Werror=format-security -Wall -DDEBIAN -O2' 'CPPFLAGS=-D_FORTIFY_SOURCE=2''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: POSIX
  value of $LC_CTYPE: en_US.UTF-8
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: en_DK
  value of $LANG: POSIX
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  display-time-mode: t
  show-paren-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
<escape> x r e p o r t <tab> <return>

Recent messages:
Loading /etc/emacs/site-start.d/50latex-cjk-common.el (source)...done
Loading /etc/emacs/site-start.d/50latex-cjk-thai.el (source)...done
Loading /etc/emacs/site-start.d/50ledger.el (source)...done
Loading /etc/emacs/site-start.d/50psvn.el (source)...done
Loading /etc/emacs/site-start.d/50rnc-mode.el (source)...done
Loading /etc/emacs/site-start.d/50thailatex.el (source)...done
Loading /etc/emacs/site-start.d/50w3m-el.el (source)...done
Loading /home/vlefevre/share/emacs/site-lisp/mutteditor.el (source)...done
Loading time...done
For information about GNU Emacs and the GNU system, type C-h C-a.

Load-path shadows:
/usr/share/emacs23/site-lisp/css-mode/css-mode hides /usr/share/emacs/site-lisp/css-mode/css-mode
/usr/share/emacs23/site-lisp/html-helper-mode/tempo hides /usr/share/emacs/site-lisp/html-helper-mode/tempo
/usr/share/emacs23/site-lisp/html-helper-mode/visual-basic-mode hides /usr/share/emacs/site-lisp/html-helper-mode/visual-basic-mode
/usr/share/emacs23/site-lisp/html-helper-mode/hhm-config hides /usr/share/emacs/site-lisp/html-helper-mode/hhm-config
/usr/share/emacs23/site-lisp/html-helper-mode/html-helper-mode hides /usr/share/emacs/site-lisp/html-helper-mode/html-helper-mode
/usr/share/emacs/23.4/site-lisp/debian-startup hides /usr/share/emacs/site-lisp/debian-startup
/usr/share/emacs/23.4/site-lisp/cmake-data/cmake-mode hides /usr/share/emacs/site-lisp/cmake-mode
/usr/share/emacs23/site-lisp/flim/sha1 hides /usr/share/emacs/23.4/lisp/sha1
/usr/share/emacs23/site-lisp/flim/hex-util hides /usr/share/emacs/23.4/lisp/hex-util
/usr/share/emacs23/site-lisp/flim/md4 hides /usr/share/emacs/23.4/lisp/md4
/usr/share/emacs23/site-lisp/html-helper-mode/tempo hides /usr/share/emacs/23.4/lisp/tempo
/usr/share/emacs23/site-lisp/dictionaries-common/ispell hides /usr/share/emacs/23.4/lisp/textmodes/ispell
/usr/share/emacs23/site-lisp/dictionaries-common/flyspell hides /usr/share/emacs/23.4/lisp/textmodes/flyspell
/usr/share/emacs23/site-lisp/css-mode/css-mode hides /usr/share/emacs/23.4/lisp/textmodes/css-mode
/usr/share/emacs23/site-lisp/flim/hmac-md5 hides /usr/share/emacs/23.4/lisp/net/hmac-md5
/usr/share/emacs23/site-lisp/flim/sasl-ntlm hides /usr/share/emacs/23.4/lisp/net/sasl-ntlm
/usr/share/emacs23/site-lisp/flim/ntlm hides /usr/share/emacs/23.4/lisp/net/ntlm
/usr/share/emacs23/site-lisp/flim/sasl hides /usr/share/emacs/23.4/lisp/net/sasl
/usr/share/emacs23/site-lisp/flim/sasl-cram hides /usr/share/emacs/23.4/lisp/net/sasl-cram
/usr/share/emacs23/site-lisp/flim/sasl-digest hides /usr/share/emacs/23.4/lisp/net/sasl-digest
/usr/share/emacs23/site-lisp/flim/hmac-def hides /usr/share/emacs/23.4/lisp/net/hmac-def
/usr/share/emacs23/site-lisp/latex-cjk-thai/thai-word hides /usr/share/emacs/23.4/lisp/language/thai-word

Features:
(shadow sort mail-extr message sendmail ecomplete rfc822 mml easymenu
mml-sec password-cache mm-decode mm-bodies mm-encode mailcap mail-parse
rfc2231 rfc2047 rfc2045 qp ietf-drums mailabbrev nnheader gnus-util
netrc time-date mm-util mail-prsvr gmm-utils wid-edit mailheader canlock
sha1 sha1-el hex-util hashcash mail-utils warnings emacsbug time
cus-start cus-load paren cc-styles cc-align cc-engine cc-vars cc-defs
regexp-opt w3m-load tooltip ediff-hook vc-hooks lisp-float-type mwheel
x-win x-dnd font-setting tool-bar dnd fontset image fringe lisp-mode
register page menu-bar rfn-eshadow timer select scroll-bar mldrag mouse
jit-lock font-lock syntax facemenu font-core frame cham georgian
utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao korean
japanese hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese case-table epa-hook jka-cmpr-hook help simple abbrev
loaddefs button minibuffer faces cus-face files text-properties overlay
md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote make-network-process dbusbind
system-font-setting font-render-setting gtk x-toolkit x multi-tty emacs)

bug#11263: 23.4; shell-script: << does not always mean here-document

[Stefan Monnier]

> When I type << in shell-script mode, Emacs thinks this begins a
> here-document. This is not always the case, e.g. in the following
> lines:

> foo='bar<<'
> echo "${foo%<<}"

Emacs handles these correctly, AFAICT.

> echo $((1<<8))
> echo $[1<<8]

But these are confused for here-documents, indeed.


        Stefan

bug#11263: 23.4; shell-script: << does not always mean here-document

[Vincent Lefevre]

On 2012-04-17 14:40:45 -0400, Stefan Monnier wrote:
> > When I type << in shell-script mode, Emacs thinks this begins a
> > here-document. This is not always the case, e.g. in the following
> > lines:
> 
> > foo='bar<<'
> > echo "${foo%<<}"
> 
> Emacs handles these correctly, AFAICT.

No, unless there is something specific to Debian or this has been
fixed recently (Debian has GNU Emacs 23.4.1). To reproduce, type:
emacs -q foo.sh

Then in the Emacs window:

foo='bar<<

This produces:

foo='bar<<EOF

EOF

-- 
Vincent Lefèvre <vincent@vinc17.net> - Web: <http://www.vinc17.net/>
100% accessible validated (X)HTML - Blog: <http://www.vinc17.net/blog/>
Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)

bug#11263: 23.4; shell-script: << does not always mean here-document

[Glenn Morris]

Vincent Lefevre wrote:

> No, unless there is something specific to Debian or this has been
> fixed recently (Debian has GNU Emacs 23.4.1).

Last August:

http://debbugs.gnu.org/9333

bug#11263: 23.4; shell-script: << does not always mean here-document

[Glenn Morris]

Glenn Morris wrote:

> http://debbugs.gnu.org/9333

PS fix was not in 23.4; will be in 24.1.

bug#11263: 23.4; shell-script: << does not always mean here-document

[Vincent Lefevre]

On 2012-04-17 20:35:25 -0400, Glenn Morris wrote:
> Glenn Morris wrote:
> 
> > http://debbugs.gnu.org/9333
> 
> PS fix was not in 23.4; will be in 24.1.

OK. In the mean time, adding the (nth 8 (syntax-ppss)) line to
sh-script.el in Debian solves the problem with strings.

-- 
Vincent Lefèvre <vincent@vinc17.net> - Web: <http://www.vinc17.net/>
100% accessible validated (X)HTML - Blog: <http://www.vinc17.net/blog/>
Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)

bug#11263: 23.4; shell-script: << does not always mean here-document

[Glenn Morris]

Also, just in case it's not obvious, you can use C-q < to stop it being
expanded as a here-doc.

bug#8196:

[Andreas Röhler]

IMO it's an interesting proposal

What about binding that at `indent-tabs-mode'?
If the default just changes, bug-reports resp. feature requests may drop in from the other side than.

Andreas