GNU bug report logs - #14332
24.3; Octave indentation bug

Previous Next

To add a comment to this bug, you must first unarchive it, by sending
a message to control AT debbugs.gnu.org, with unarchive 14332 in the body.
You can then email your comments to 14332 AT debbugs.gnu.org in the normal way.

Toggle the display of automated, internal messages from the tracker.

Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Leo Liu <sdl.web <at> gmail.com>
To: bug-gnu-emacs <at> gnu.org
Subject: 24.3; Octave indentation bug
Date: Thu, 02 May 2013 12:04:44 +0800

Indent the following lines in octave mode

if (true)
  a = (1 \(2-3));
else
  a = 0;
endif

gives me

if (true)
  a = (1 \(2-3));
                else
                  a = 0;
                endif


It seems treating \ as escape outside strings is incorrect. Is the
following fix is correct?


diff --git a/lisp/progmodes/octave.el b/lisp/progmodes/octave.el
index a58fdefb..1e2c2425 100644
--- a/lisp/progmodes/octave.el
+++ b/lisp/progmodes/octave.el
@@ -233,7 +233,7 @@ (defvar octave-mode-syntax-table
     (modify-syntax-entry ?& "."   table)
     (modify-syntax-entry ?| "."   table)
     (modify-syntax-entry ?! "."   table)
-    (modify-syntax-entry ?\\ "\\" table)
+    (modify-syntax-entry ?\\ "." table)
     (modify-syntax-entry ?\' "."  table)
     ;; Was "w" for abbrevs, but now that it's not necessary any more,
     (modify-syntax-entry ?\` "."  table)

Message #8 received at 14332 <at> debbugs.gnu.org (full text, mbox):

From: Stefan Monnier <monnier <at> iro.umontreal.ca>
To: Leo Liu <sdl.web <at> gmail.com>
Cc: 14332 <at> debbugs.gnu.org
Subject: Re: bug#14332: 24.3; Octave indentation bug
Date: Sun, 05 May 2013 01:29:45 -0400

> It seems treating \ as escape outside strings is incorrect. Is the
> following fix is correct?
[..]
> -    (modify-syntax-entry ?\\ "\\" table)
> +    (modify-syntax-entry ?\\ "." table)

Wouldn't that mess up the case of

  a = "hello\"there";

?

        Stefan

Message #11 received at 14332 <at> debbugs.gnu.org (full text, mbox):

From: Leo Liu <sdl.web <at> gmail.com>
To: Stefan Monnier <monnier <at> iro.umontreal.ca>
Cc: 14332 <at> debbugs.gnu.org
Subject: Re: bug#14332: 24.3; Octave indentation bug
Date: Sun, 05 May 2013 13:35:49 +0800

On 2013-05-05 13:29 +0800, Stefan Monnier wrote:
> Wouldn't that mess up the case of
>
>   a = "hello\"there";

Yes it does. How to fix this bug properly?

Leo

Message #14 received at 14332 <at> debbugs.gnu.org (full text, mbox):

From: Stefan Monnier <monnier <at> iro.umontreal.ca>
To: Leo Liu <sdl.web <at> gmail.com>
Cc: 14332 <at> debbugs.gnu.org
Subject: Re: bug#14332: 24.3; Octave indentation bug
Date: Sun, 05 May 2013 03:17:11 -0400

>> Wouldn't that mess up the case of
>> a = "hello\"there";
> Yes it does. How to fix this bug properly?

You'll probably need to add some syntax-propertize case.
What does "(1 \(2-3))" mean in Octave?  Where else can \ appear in
Octave code?


        Stefan

Message #17 received at 14332 <at> debbugs.gnu.org (full text, mbox):

From: Leo Liu <sdl.web <at> gmail.com>
To: Stefan Monnier <monnier <at> iro.umontreal.ca>
Cc: 14332 <at> debbugs.gnu.org
Subject: Re: bug#14332: 24.3; Octave indentation bug
Date: Sun, 05 May 2013 15:28:13 +0800

On 2013-05-05 15:17 +0800, Stefan Monnier wrote:
> You'll probably need to add some syntax-propertize case.
> What does "(1 \(2-3))" mean in Octave?  Where else can \ appear in
> Octave code?

A \ 1 ≡ inv(A) # one over matrix A, with some optimisation

if A is a scalar, A \ 1 = 1 / A.

so \ is an operator.

Leo

Message #20 received at 14332 <at> debbugs.gnu.org (full text, mbox):

From: Stefan Monnier <monnier <at> iro.umontreal.ca>
To: Leo Liu <sdl.web <at> gmail.com>
Cc: 14332 <at> debbugs.gnu.org
Subject: Re: bug#14332: 24.3; Octave indentation bug
Date: Sun, 05 May 2013 21:04:14 -0400

>> You'll probably need to add some syntax-propertize case.
>> What does "(1 \(2-3))" mean in Octave?  Where else can \ appear in
>> Octave code?

> A \ 1 ≡ inv(A) # one over matrix A, with some optimisation

> if A is a scalar, A \ 1 = 1 / A.

> so \ is an operator.

Then your best bet is probably to put in the mode's syntax-table the
syntax corresponding to the most common use of \ (either as an escape
char in strings or as an operator), and then use syntax-propertize to
put the other syntax on the other case (where you can check (nth
3 (syntax-ppss (math-beginning 0))) to see if you're within a string).


        Stefan

Message #23 received at 14332 <at> debbugs.gnu.org (full text, mbox):

From: Leo Liu <sdl.web <at> gmail.com>
To: Stefan Monnier <monnier <at> iro.umontreal.ca>
Cc: 14332 <at> debbugs.gnu.org
Subject: Re: bug#14332: 24.3; Octave indentation bug
Date: Mon, 06 May 2013 11:29:42 +0800

[Message part 1 (text/plain, inline)]

On 2013-05-06 09:04 +0800, Stefan Monnier wrote:
> Then your best bet is probably to put in the mode's syntax-table the
> syntax corresponding to the most common use of \ (either as an escape
> char in strings or as an operator), and then use syntax-propertize to
> put the other syntax on the other case (where you can check (nth
> 3 (syntax-ppss (math-beginning 0))) to see if you're within a string).

What I would like is to have \ mean "." unless it is in double-quoted
strings where it should be "\\". I have the following non-working patch.
Ideas?

diff --git a/lisp/progmodes/octave.el b/lisp/progmodes/octave.el
index 2e848600..d5a1af2b 100644
--- a/lisp/progmodes/octave.el
+++ b/lisp/progmodes/octave.el
@@ -137,6 +137,8 @@ (defun octave-syntax-propertize-function (start end)
   (goto-char start)
   (octave-syntax-propertize-sqs end)
   (funcall (syntax-propertize-rules
+            ("\\\\" (0 (when (eq (nth 3 (syntax-ppss (match-beginning 0))) ?\")
+                         "\\")))
             ;; Try to distinguish the string-quotes from the transpose-quotes.
             ("\\(?:^\\|[[({,; ]\\)\\('\\)"
              (1 (prog1 "\"'" (octave-syntax-propertize-sqs end)))))
@@ -242,7 +244,7 @@ (defvar octave-mode-syntax-table
     (modify-syntax-entry ?& "."   table)
     (modify-syntax-entry ?| "."   table)
     (modify-syntax-entry ?! "."   table)
-    (modify-syntax-entry ?\\ "\\" table)
+    (modify-syntax-entry ?\\ "."  table)
     (modify-syntax-entry ?\' "."  table)
     ;; Was "w" for abbrevs, but now that it's not necessary any more,
     (modify-syntax-entry ?\` "."  table)

[oct_ind.m (text/plain, attachment)]

Message #26 received at 14332 <at> debbugs.gnu.org (full text, mbox):

From: Leo Liu <sdl.web <at> gmail.com>
To: Stefan Monnier <monnier <at> iro.umontreal.ca>
Cc: 14332 <at> debbugs.gnu.org
Subject: Re: bug#14332: 24.3; Octave indentation bug
Date: Mon, 06 May 2013 16:26:13 +0800

On 2013-05-06 11:29 +0800, Leo Liu wrote:
> What I would like is to have \ mean "." unless it is in double-quoted
> strings where it should be "\\".

This patch seems working. This is the first time I am using the
syntax-table property. Stefan, do you see any problem with the patch?

diff --git a/lisp/progmodes/octave.el b/lisp/progmodes/octave.el
index 2e848600..66fda302 100644
--- a/lisp/progmodes/octave.el
+++ b/lisp/progmodes/octave.el
@@ -134,6 +134,12 @@ (defvar octave-font-lock-keywords
   "Additional Octave expressions to highlight.")
 
 (defun octave-syntax-propertize-function (start end)
+  (funcall (syntax-propertize-rules
+            ("\\\\" (0 (when (eq (nth 3 (save-excursion
+                                          (syntax-ppss (match-beginning 0))))
+                                 ?\")
+                         (string-to-syntax "\\")))))
+           start end)
   (goto-char start)
   (octave-syntax-propertize-sqs end)
   (funcall (syntax-propertize-rules
@@ -242,7 +248,7 @@ (defvar octave-mode-syntax-table
     (modify-syntax-entry ?& "."   table)
     (modify-syntax-entry ?| "."   table)
     (modify-syntax-entry ?! "."   table)
-    (modify-syntax-entry ?\\ "\\" table)
+    (modify-syntax-entry ?\\ "."  table)
     (modify-syntax-entry ?\' "."  table)
     ;; Was "w" for abbrevs, but now that it's not necessary any more,
     (modify-syntax-entry ?\` "."  table)

Message #29 received at 14332 <at> debbugs.gnu.org (full text, mbox):

From: Stefan Monnier <monnier <at> iro.umontreal.ca>
To: Leo Liu <sdl.web <at> gmail.com>
Cc: 14332 <at> debbugs.gnu.org
Subject: Re: bug#14332: 24.3; Octave indentation bug
Date: Mon, 06 May 2013 10:48:18 -0400

> +            ("\\\\" (0 (when (eq (nth 3 (save-excursion
> +                                          (syntax-ppss (match-beginning 0))))
> +                                 ?\")
> +                         (string-to-syntax "\\")))))

The rule looks OK, but why not put it inside the subsequent
`syntax-propertize-rules'?


        Stefan

Message #32 received at 14332 <at> debbugs.gnu.org (full text, mbox):

From: Leo Liu <sdl.web <at> gmail.com>
To: Stefan Monnier <monnier <at> iro.umontreal.ca>
Cc: 14332 <at> debbugs.gnu.org
Subject: Re: bug#14332: 24.3; Octave indentation bug
Date: Mon, 06 May 2013 23:57:20 +0800

On 2013-05-06 22:48 +0800, Stefan Monnier wrote:
> The rule looks OK, but why not put it inside the subsequent
> `syntax-propertize-rules'?

Wouldn't this (octave-syntax-propertize-sqs end) before the
syntax-propertize-rules form causes some \'s to be missed?

Leo

Message #35 received at 14332 <at> debbugs.gnu.org (full text, mbox):

From: Stefan Monnier <monnier <at> iro.umontreal.ca>
To: Leo Liu <sdl.web <at> gmail.com>
Cc: 14332 <at> debbugs.gnu.org
Subject: Re: bug#14332: 24.3; Octave indentation bug
Date: Mon, 06 May 2013 17:37:39 -0400

>> The rule looks OK, but why not put it inside the subsequent
>> `syntax-propertize-rules'?
> Wouldn't this (octave-syntax-propertize-sqs end) before the
> syntax-propertize-rules form causes some \'s to be missed?

No, octave-syntax-propertize-sqs just skips over the contents of
single-quoted strings and from what you say you only want to handle
backslash in double-quoted strings.


        Stefan

Message #40 received at 14332-done <at> debbugs.gnu.org (full text, mbox):

From: Leo Liu <sdl.web <at> gmail.com>
To: Stefan Monnier <monnier <at> iro.umontreal.ca>
Cc: 14332-done <at> debbugs.gnu.org
Subject: Re: bug#14332: 24.3; Octave indentation bug
Date: Tue, 07 May 2013 07:58:10 +0800

Fixed in trunk.

On 2013-05-07 05:37 +0800, Stefan Monnier wrote:
> No, octave-syntax-propertize-sqs just skips over the contents of
> single-quoted strings and from what you say you only want to handle
> backslash in double-quoted strings.

Thank you, Stefan, for the help. Much appreciated.

Leo

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.