bug#4737: 23.1.50; C-j in *scratch* after a hash table constant errors with void-function

bug#4737: 23.1.50; C-j in *scratch* after a hash table constant errors with void-function

[Aidan Kehoe]

Hello!

Please write in English if possible, because the Emacs maintainers
usually do not have translators to read other languages for them.

Your bug report will be posted to the emacs-pretest-bug@gnu.org mailing list.

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug:

In *scratch*: 

(progn
  (setq print-length nil)
  (make-hash-table)) 
=> #s(hash-table size 65 test eql rehash-size 1.5 rehash-threshold 0.8 data ())

#s(hash-table size 65 test eql rehash-size 1.5 rehash-threshold 0.8 data
 ())
=> 
Debugger entered--Lisp error: (void-function hash-table)
  (hash-table size 65 test eql rehash-size 1.5 rehash-threshold 0.8 data nil)
  eval((hash-table size 65 test eql rehash-size 1.5 rehash-threshold 0.8 data nil))
  eval-last-sexp-1(t)
  eval-last-sexp(t)
  eval-print-last-sexp()
  call-interactively(eval-print-last-sexp nil nil)

However, this succeeds: 

(car (list
      #s(hash-table size 65 test eql rehash-size 1.5 rehash-threshold 0.8 data ())))
=> #s(hash-table size 65 test eql rehash-size 1.5 rehash-threshold 0.8 data ())

XEmacs handles the problem in #'forward-sexp, details here: 

http://hg.debian.org/hg/xemacs/xemacs/file/a27de91ae83c/lisp/lisp.el#l55

When I use the XEmacs version of #'forward-sexp, the problem goes away. 

Goodbye, 

Aidan

If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
If you would like to further debug the crash, please read the file
/Sources/emacs/nextstep/Emacs.app/Contents/Resources/etc/DEBUG for instructions.


In GNU Emacs 23.1.50.1 (i386-apple-darwin8.11.1, NS apple-appkit-824.48)
 of 2009-09-30 on bonbon
Windowing system distributor `Apple', version 10.3.824
configured using `configure  '--with-ns' '--enable-asserts' '--enable-maintainer-mode' '--enable-cocoa-experimental-ctrl-g' '--with-xpm' '--with-jpeg' '--with-tiff' '--with-png' 'LDFLAGS=-L/opt/local/lib -L/usr/X11R6/lib -L/usr/local/lib' 'CPPFLAGS=-I/opt/local/include -I/usr/X11R6/include -I/usr/local/include''

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

Major mode: Lisp Interaction

Minor modes in effect:
  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
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n 
C-n C-n C-n C-n C-n C-n C-n C-v C-v C-v C-v C-v C-v 
C-v C-v C-v C-v <escape> v C-v C-v C-v C-v C-v <prior> 
<next> <next> <prior> <prior> <prior> <prior> <prior> 
<prior> <prior> <prior> <prior> C-x b * s c <tab> <return> 
( k i l l e C-a C-k <f1> v p r i n t - l e <tab> n 
<tab> <return> C-x o C-n C-n C-n C-n C-n C-e C-b C-b 
C-b C-b <return> C-x o C-n C-x o C-e C-b C-b C-b <return> 
C-x o C-x b * s c <tab> C-g C-x o C-n C-n C-x o C-x 
b * s c <tab> <return> <escape> > <return> <return> 
( s e t q SPC e v a l - e x p r e s s i o n - p r i 
n t - l e n g t h SPC n i l ) C-j C-p C-p C-p C-p C-p 
C-p C-e C-j C-p C-d C-d ( l e n g t h SPC ' C-e ) C-j 
C-x o C-x o C-p C-p C-n C-n C-n C-p C-p C-p C-p C-k 
C-k C-k C-p C-e C-j C-p C-e C-j q <escape> x r e p 
o r t - e m a c s - b u g C-g C-p <return> <return> 
C-p ( c o n s SPC . C-a ( c a r SPC C-e C-n C-e <backspace> 
) <return> <tab> n i l ) ) C-j C-x o C-p C-p C-f C-f 
C-f C-f C-f C-f C-f C-f C-d C-n C-n C-j C-x o q <escape> 
x r e p o r t - e m a c s - b u g <return>

Recent messages:
Making completion list...
Type C-x 1 to delete the help window.
uncompressing simple.el.gz...done
Quit
Mark set
Entering debugger...
Back to top level.
Quit
Entering debugger...
Back to top level.

-- 
¿Dónde estará ahora mi sobrino Yoghurtu Nghe, que tuvo que huir
precipitadamente de la aldea por culpa de la escasez de rinocerontes?

bug#4737: 23.1.50; C-j in *scratch* after a hash table constant errors with void-function

[Chong Yidong]

> In *scratch*:
>
> (progn
>   (setq print-length nil)
>   (make-hash-table))
> => #s(hash-table size 65 test eql rehash-size 1.5 rehash-threshold 0.8 data ())
>
> #s(hash-table size 65 test eql rehash-size 1.5 rehash-threshold 0.8 data
>  ())
> =>
> Debugger entered--Lisp error: (void-function hash-table)
>   (hash-table size 65 test eql rehash-size 1.5 rehash-threshold 0.8 data nil)
>   eval((hash-table size 65 test eql rehash-size 1.5 rehash-threshold 0.8 data nil))
>   eval-last-sexp-1(t)
>   eval-last-sexp(t)
>   eval-print-last-sexp()
>   call-interactively(eval-print-last-sexp nil nil)

> However, this succeeds:

> (car (list
>       #s(hash-table size 65 test eql rehash-size 1.5 rehash-threshold 0.8 data ())))
> => #s(hash-table size 65 test eql rehash-size 1.5 rehash-threshold 0.8 data ())

> XEmacs handles the problem in #'forward-sexp

I think it's safer to handle it in preceding-sexp.  Could you test the
patch below?


*** emacs/lisp/emacs-lisp/lisp-mode.el.~1.247.~	2009-09-27 18:51:01.000000000 -0400
--- emacs/lisp/emacs-lisp/lisp-mode.el	2009-10-17 23:41:53.000000000 -0400
***************
*** 673,678 ****
--- 673,682 ----
  	  (when (eq (preceding-char) ??)
  	    (forward-char -1)))
  
+ 	;; Skip over hash table read syntax
+ 	(when (looking-back "#s")
+ 	  (forward-char -2))
+ 
  	;; Skip over `#N='s.
  	(when (eq (preceding-char) ?=)
  	  (let (labeled-p)

bug#4737: 23.1.50; C-j in *scratch* after a hash table constant errors with void-function

[Stefan Monnier]

> + 	;; Skip over hash table read syntax
> + 	(when (looking-back "#s")
> + 	  (forward-char -2))

Calling looking-back without a limit argument is asking for trouble (it
has complexity O(size of buffer) or worse).


        Stefan

bug#4737: 23.1.50; C-j in *scratch* after a hash table constant errors with void-function

[martin rudalics]

 > Calling looking-back without a limit argument is asking for trouble (it
 > has complexity O(size of buffer) or worse).

Then we should make the limit argument non-optional.

martin

bug#4737: 23.1.50; C-j in *scratch* after a hash table constant errors with void-function

[Stefan Monnier]

>> Calling looking-back without a limit argument is asking for trouble (it
>> has complexity O(size of buffer) or worse).

> Then we should make the limit argument non-optional.

Feel free to do that,


        Stefan


PS: Now that we can do it compatibly via set-advertised-calling-convention.