(setq blink-matching-paren-dont-ignore-comments nil) ignored?

(setq blink-matching-paren-dont-ignore-comments nil) ignored?

[Andrew M. Scott]

I'm seeing blink-matches on parenthesese in comments with
(setq blink-matching-paren-dont-ignore-comments nil) [the default, BTW]
even though the docstring on blink-matching-paren-dont-ignore-comments 
says I shouldn't.

% emacs -q &

In the *scratch* buffer, type

(setq debug-on-error t) ; ((setq debug-on-error nil))

The parentheses will blink-match all the close-parens in the comment.

Just for completeness, comment-start's value is ";" in *scratch*.

Thanks,
Andy

In GNU Emacs 22.0.50.1 (x86_64-unknown-linux-gnu, X toolkit)
 of 2006-02-06 on chlr5836
X server distributor `The XFree86 Project, Inc', version 11.0.40201000
configured using `configure '--prefix=/stor/garray/linux_2.6.5_x86-64' '--x-includes=/usr/intel/pkgs/X11/R6.7.0-64/include' '--x-libraries=/usr/intel/pkgs/X11/R6.7.0-64/lib' 'CC=gcc' 'CFLAGS=-O2 -I/usr/intel/pkgs/X11/R6.7.0-64/include -L/usr/intel/pkgs/X11/R6.7.0-64/lib -I/usr/intel/pkgs/zlib/1.2.1-64/include -L/usr/intel/pkgs/zlib/1.2.1-64/lib  -I/usr/intel/pkgs/ncurses/5.4/include -L/usr/intel/pkgs/ncurses/5.4/lib -I/usr/intel/pkgs/libungif/4.1.3/include -L/usr/intel/pkgs/libungif/4.1.3/lib -I/usr/intel/pkgs/libpng/1.0.16rc1-64/include -L/usr/intel/pkgs/libpng/1.0.16rc1-64/lib -I/usr/intel/pkgs/jpeg/6b-64/include -L/usr/intel/pkgs/jpeg/6b-64/lib' 'LDFLAGS=-L/usr/intel/pkgs/X11/R6.7.0-64/lib -L/usr/intel/pkgs/zlib/1.2.1-64/lib -L/usr/intel/pkgs/ncurses/5.4/lib -L/usr/intel/pkgs/libungif/4.1.3/lib -L/usr/intel/pkgs/libpng/1.0.16rc1-64/lib -L/usr/intel/pkgs/jpeg/6b-64/lib -Wl,-rpath=/usr/
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 4/lib:/usr/intel/pkgs/libungif/4.1.3/lib:/usr/intel/pkgs/libpng/1.0.16rc1-64/lib:/usr/intel/pkgs/jpeg/6b-64/lib''

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: en_US.UTF-8
  locale-coding-system: utf-8
  default-enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  auto-compression-mode: t
  tool-bar-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
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  line-number-mode: t

Re: (setq blink-matching-paren-dont-ignore-comments nil) ignored?

[Richard M. Stallman]

    (setq debug-on-error t) ; ((setq debug-on-error nil))

    The parentheses will blink-match all the close-parens in the comment.

The effect of the feature is to ignore previous parens that are in
comments.

I will clarify the documentation.

Re: (setq blink-matching-paren-dont-ignore-comments nil) ignored?

[Andrew M. Scott]

    >>>>> "Richard" == Richard M Stallman <rms@gnu.org> writes:
    Richard>     (setq debug-on-error t) ; ((setq debug-on-error nil))
    Richard>     The parentheses will blink-match all the close-parens
    Richard>     in the comment.

    Richard> The effect of the feature is to ignore previous parens
    Richard> that are in comments.
    Richard> I will clarify the documentation.
          
Richard, 

Unfortunately, even after reading the updated docstring several times
and experimenting, I still can't visualize what
blink-matching-paren-dont-ignore-comments is supposed to do. I also
looked for an example in (Info-find-node "emacs" "Matching") but there
is no mention of this variable there, either.


M-x describe-variable blink-matching-paren-dont-ignore-comments:

blink-matching-paren-dont-ignore-comments is a variable defined in `simple.el'.
Its value is t

Documentation:
*nil means `blink-matching-paren' ignores comments.
More precisely, when looking for the matching parenthesis,
it skips the contents of comments that end before point.

Puzzled,
Andy Scott

Re: (setq blink-matching-paren-dont-ignore-comments nil) ignored?

[Mathias Dahl]

> Unfortunately, even after reading the updated docstring several times
> and experimenting
> ...
> Documentation:
> *nil means `blink-matching-paren' ignores comments.
> More precisely, when looking for the matching parenthesis,
> it skips the contents of comments that end before point.

The docstring gives the impression of handling the following case:

(

;;;;;;;; ( <=== This is skipped

)<-- Point

When point is at the position marked above, the correct paren will be
matched if the value of this variable is nil. Useful. However, when I
set it to `t' it still skips the one in the comment.

I tested in the *scratch* buffer.

Re: (setq blink-matching-paren-dont-ignore-comments nil) ignored?

[Richard M. Stallman]

    Unfortunately, even after reading the updated docstring several times
    and experimenting, I still can't visualize what
    blink-matching-paren-dont-ignore-comments is supposed to do.

I regret this, but I cannot see any way to make it any clearer.

Re: (setq blink-matching-paren-dont-ignore-comments nil) ignored?

[Richard M. Stallman]

    (

    ;;;;;;;; ( <=== This is skipped

    )<-- Point

    When point is at the position marked above, the correct paren will be
    matched if the value of this variable is nil. Useful. However, when I
    set it to `t' it still skips the one in the comment.

The blink-matching-paren feature shows you the matching open-paren
when you insert a close-paren.  So try this:

    (

    ;;;;;;;; ( <=== This is skipped

and insert a ).  You will see that this variable takes effect.

Re: (setq blink-matching-paren-dont-ignore-comments nil) ignored?

[Andrew M. Scott]

Richard,

    Richard>     (

    Richard>     ;;;;;;;; ( <=== This is skipped

    Richard> and insert a ). You will see that this variable takes
    Richard> effect.

1. Thanks to the examples provided by you & Mathias Dahl, I now
   understand the function of variable
   blink-matching-paren-dont-ignore-comments. Thank you both.

2. The current negative logic embodied in the variable name can be
   confusing, e.g.:

   (setq blink-matching-paren-dont-ignore-comments t)

   I think it would be clearer if positive logic were used, e.g.

   (setq blink-matching-paren-ignore-comments t)
   (setq blink-matching-paren-ignore-comments nil)

   with docstring:

   blink-matching-paren-ignore-comments is a variable defined in `simple.el'.
   Its value is t

   Documentation:
   *t means `blink-matching-paren' ignores comments.
   More precisely, when looking for the matching open parenthesis,
   skips the contents of comments that end before point.

3. I also recommend than an example similar to yours/Mathias's in this
   thread be added to the (Info-find-node "emacs" "Matching") section.

Thank you,
Andy Scott

Re: (setq blink-matching-paren-dont-ignore-comments nil) ignored?

[Richard M. Stallman]

    2. The current negative logic embodied in the variable name can be
       confusing, e.g.:

       (setq blink-matching-paren-dont-ignore-comments t)

       I think it would be clearer if positive logic were used, e.g.

       (setq blink-matching-paren-ignore-comments t)

I agree, but I am not sure it is worth changing this variable.  I
wonder if anyone really wants the other non-default behavior.

I don't think it is worth putting this var in the manual.