longlines-mode and comments

longlines-mode and comments

[David Reitter]

emacs-lisp-mode, or latex-mode (AUCTeX)

Turn on longlines-mode.

Paste a long line (paragraph in the long-lines sense) into the buffer,  
which should be wrapped correctly and displayed as a paragraph of text.

Select the entire paragraph and call `comment-region'.

Result: The comment mark (;; or % or whatever) is placed all over the  
lines, and only the first line has it in the right place, i.e. at the  
beginning.

(Also, when `longlines-wrap-follows-window-size' is turned on, then  
the line/paragraph is reformatted.)

The expected (correct) behavior would be to add the comment command at  
the beginning of the line in the file, i.e. at the beginning of the  
paragraph, that is, after each hard return.

Note that the other expected thing there is that the syntax  
highlighting (font-lock) works, i.e. that the whole comment is shown  
using the right face. This, IMHO, is a second bug.



In GNU Emacs 22.1.50.1 (i386-apple-darwin8.11.1, Carbon Version 1.6.0)
  of 2007-11-27 on plume.sr.unh.edu - Aquamacs Distribution 1.2
Windowing system distributor `Apple Inc.', version 10.5.1
configured using `configure  '--without-x' '--prefix=/usr/local''

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: nil
   locale-coding-system: iso-8859-1
   default-enable-multibyte-characters: t

Major mode: PDFLaTeX/F

Minor modes in effect:
   reftex-mode: t
   TeX-fold-mode: t
   outline-minor-mode: t
   TeX-PDF-mode: t
   smart-frame-positioning-mode: t
   aquamacs-styles-mode: t
   shell-dirtrack-mode: t
   recentf-mode: t
   encoded-kbd-mode: t
   osx-key-mode: t
   longlines-mode: t
   show-paren-mode: t
   delete-selection-mode: t
   pc-selection-mode: t
   cua-mode: t
   tooltip-mode: t
   mac-input-method-mode: t
   tool-bar-mode: 0
   mouse-wheel-mode: t
   use-hard-newlines: t
   menu-bar-mode: t
   file-name-shadow-mode: t
   global-font-lock-mode: t
   font-lock-mode: t
   blink-cursor-mode: t
   unify-8859-on-encoding-mode: t
   utf-translate-cjk-mode: t
   auto-compression-mode: t
   column-number-mode: t
   line-number-mode: t
   transient-mark-mode: t

Recent input:
<left> <left> <up> <right> <backspace> <up> <delete>
<backspace> SPC <down> <backspace> <delete> <down>
<right> <right> <right> <right> <right> <right> <right>
<right> <right> <right> <right> <right> <right> <right>
<right> <right> <right> <right> <right> <right> <right>
<right> <right> <right> <right> <right> <right> <right>
<right> <delete> <delete> <down> <left> <left> <left>
<left> <left> <left> <left> <left> <left> <left> <left>
<left> <left> <left> <left> <left> <left> <left> <left>
<left> <left> <left> <left> <left> <left> <left> <left>
<left> <left> <left> <left> <left> <left> <left> <left>
<backspace> <backspace> <backspace> SPC M-q <up> <up>
<up> <up> <right> <down> % SPC <down> <up> <left> <left>
<return> <down> <left> <return> <left> <left> <return>
<down> <backspace> SPC <down> <left> <left> <left>
<left> <right> % SPC <left> <left> <return> <down>
<down-mouse-1> <mouse-1> A-s <down-mouse-1> <mouse-1>
<delete> <delete> A-s <menu-bar> <buffer> "model-chapter.tex"
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1> <mouse-1>
<mouse-1> <mouse-1> <mouse-1> <mouse-1> <down-mouse-1>
<mouse-movement> <mouse-movement> <mouse-movement>
<mouse-movement> <drag-mouse-1> A-' A-z <delete> <delete>
<down-mouse-1> <mouse-1> <delete> <delete> <up> <right>
<down> A-s C-h k A-' <help-echo> <switch-frame> C-h
f c o m m e n t - r e g <tab> <return> <switch-frame>
<down-mouse-1> <mouse-movement> <mouse-movement> <mouse-movement>
<mouse-movement> <drag-mouse-1> <escape> x c o m m
<tab> e n t - r e g i o n <return> <help-echo> <S-down-mouse-1>
<S-mouse-1> A-c <menu-bar> <help-menu> <report-ema
cs-bug>

Recent messages:
Quit
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Wrote /Users/dr/PhD/thesis/introduction-chapter.tex [2 times]
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Re: longlines-mode and comments

[martin rudalics]

> emacs-lisp-mode, or latex-mode (AUCTeX)
> 
> Turn on longlines-mode.
> 
> Paste a long line (paragraph in the long-lines sense) into the buffer,  
> which should be wrapped correctly and displayed as a paragraph of text.
> 
> Select the entire paragraph and call `comment-region'.
> 
> Result: The comment mark (;; or % or whatever) is placed all over the  
> lines, and only the first line has it in the right place, i.e. at the  
> beginning.
> 
> (Also, when `longlines-wrap-follows-window-size' is turned on, then  the 
> line/paragraph is reformatted.)
> 
> The expected (correct) behavior would be to add the comment command at  
> the beginning of the line in the file, i.e. at the beginning of the  
> paragraph, that is, after each hard return.
> 
> Note that the other expected thing there is that the syntax  
> highlighting (font-lock) works, i.e. that the whole comment is shown  
> using the right face. This, IMHO, is a second bug.

It's hardly trivial.  Have a look at the thread starting with:

http://lists.gnu.org/archive/html/emacs-devel/2006-11/msg00634.html

Re: longlines-mode and comments

[David Reitter]

On 29 Nov 2007, at 10:34, martin rudalics wrote:

>> (Also, when `longlines-wrap-follows-window-size' is turned on,  
>> then  the line/paragraph is reformatted.)
>> The expected (correct) behavior would be to add the comment command  
>> at  the beginning of the line in the file, i.e. at the beginning of  
>> the  paragraph, that is, after each hard return.
>> Note that the other expected thing there is that the syntax   
>> highlighting (font-lock) works, i.e. that the whole comment is  
>> shown  using the right face. This, IMHO, is a second bug.
>
> It's hardly trivial.  Have a look at the thread starting with:
>
> http://lists.gnu.org/archive/html/emacs-devel/2006-11/msg00634.html

Sure, one can fix longlines to deal with further eventualities. But  
each of them is going to be a further hack, because code everywhere  
assumes that a line in the buffer is a line in the file, and  
everything else would be a lot more complicated.

Longlines mode has a number of shortcomings that can't be addressed  
within the current architecture: for instance it looks rather bad with  
variable-width fonts and with different font sizes in the buffer, for  
instance when editing long LaTeX documents using AUCTeX.

The alternative is display-time word wrap (DTWW), and Kim Storm has  
developed a patch that was supposed to be applied after the 22.1  
release:

http://www.mail-archive.com/emacs-pretest-bug@gnu.org/msg03729.html

There was a good discussion in 2005 with the same conclusion:

http://www.nabble.com/flyspell-+-longlines:-hang-wait-t448677.html

I wish this could be updated and applied. Every modern text editor has  
this. It is really needed when you want to write text and not code on  
non-TTY displays.

Re: longlines-mode and comments

[Richard Stallman]

    The alternative is display-time word wrap (DTWW), and Kim Storm has  
    developed a patch that was supposed to be applied after the 22.1  
    release:

    http://www.mail-archive.com/emacs-pretest-bug@gnu.org/msg03729.html

Would people please study that patch and report?

Re: longlines-mode and comments

[David Reitter]

I posted this a while ago:

>> emacs-lisp-mode, or latex-mode (AUCTeX)
>> Turn on longlines-mode.
>> Paste a long line (paragraph in the long-lines sense) into the  
>> buffer,  which should be wrapped correctly and displayed as a  
>> paragraph of text.
>> Select the entire paragraph and call `comment-region'.
>> Result: The comment mark (;; or % or whatever) is placed all over  
>> the  lines, and only the first line has it in the right place, i.e.  
>> at the  beginning.

would the following be solution?
It works for me.

*** newcomment.el	28 Nov 2007 12:14:50 +0000	1.101.2.2
--- newcomment.el	17 Dec 2007 18:22:18 +0000	
***************
*** 1035,1040 ****
--- 1035,1041 ----
     (comment-normalize-vars)
     (if (> beg end) (let (mid) (setq mid beg beg end end mid)))
     (save-excursion
+     (if longlines-mode (longlines-decode-region beg end))
       ;; FIXME: maybe we should call uncomment depending on ARG.
       (funcall comment-region-function beg end arg)))


What remains is:

>> (Also, when `longlines-wrap-follows-window-size' is turned on,  
>> then  the line/paragraph is reformatted.)
>> The expected (correct) behavior would be to add the comment command  
>> at  the beginning of the line in the file, i.e. at the beginning of  
>> the  paragraph, that is, after each hard return.
>> Note that the other expected thing there is that the syntax   
>> highlighting (font-lock) works, i.e. that the whole comment is  
>> shown  using the right face. This, IMHO, is a second bug.

It seems like `longlines-wrap-line' has a provision for the case, but  
it doesn't work (I don't understand that code). What does work is to  
not comment wrap lines at all until a better solution is found.


*** longlines.el	28 Nov 2007 12:14:50 +0000	1.33.2.5
--- longlines.el	17 Dec 2007 18:37:40 +0000	
***************
*** 257,267 ****
   If wrapping is performed, point remains on the line.  If the line  
does
   not need to be wrapped, move point to the next line and return t."
     (if (longlines-set-breakpoint)
!       (progn (insert-before-markers ?\n)
! 	     (backward-char 1)
!              (delete-char -1)
! 	     (forward-char 1)
!              nil)
       (if (longlines-merge-lines-p)
           (progn (end-of-line)
        ;; After certain commands (e.g. kill-line), there may be two
--- 259,273 ----
   If wrapping is performed, point remains on the line.  If the line  
does
   not need to be wrapped, move point to the next line and return t."
     (if (longlines-set-breakpoint)
!       (progn
! 	(unless (nth 4 (syntax-ppss (point)))
! 	  ;; We are not in a comment context.
! 	  (insert-before-markers ?\n)
! 	  (backward-char 1)
! 	  (delete-char -1)
! 	
! 	  (forward-char 1))
! 	nil)
       (if (longlines-merge-lines-p)
           (progn (end-of-line)
        ;; After certain commands (e.g. kill-line), there may be two

Re: longlines-mode and comments

[martin rudalics]

 > It seems like `longlines-wrap-line' has a provision for the case, but
 > it doesn't work (I don't understand that code). What does work is to
 > not comment wrap lines at all until a better solution is found.

For some reason my Emacs hangs with your patch.

 > !     (unless (nth 4 (syntax-ppss (point)))

I think this should be tested iff a comment syntax has been defined by
the current major mode.  Moreover, the line should be wrapped when the
actual comment is not terminated by a newline.