From: Alan Mackenzie <acm@muc.de>
To: Stefan Monnier <monnier@iro.umontreal.ca>
Cc: 59213@debbugs.gnu.org
Subject: bug#59213: Emacs 29: Edebug fails to instrument a parameter whose name begins with _
Date: Mon, 14 Nov 2022 10:28:29 +0000 [thread overview]
Message-ID: <Y3IYTSTtOBZSRZ3z@ACM> (raw)
In-Reply-To: <jwvfsemi499.fsf-monnier+emacs@gnu.org>
Hello, Stefan.
On Sun, Nov 13, 2022 at 22:53:12 -0500, Stefan Monnier wrote:
> > In Emacs 29 (not started with -Q, but...),
> > I instrumented for edebug a function which looked like:
> > (defun c-trim-found-types (beg end _old-len) ....)
> > , the compilation being with lexical-binding: t.
> > During the edebug session, I attempted
> > e _old-len RET.
> The behavior depends on where you are in the *Backtrace* buffer, because
> each line in the backtrace can be in a different lexical scope.
> So please clarify on which line you were when you did the above.
I wasn't in the backtrace. I was stepping through the code in edebug.
More precisely, with this defun:
(defun add (a b _c)
(+ a b))
, instrument it for edebug. Call M-: (add 1 2 6).
The source code with active edebug now looks like:
(defun add (a b _c)
=>(+ a b))
.. e a now returns 1. e b returns 2. e _c gives the error message:
Error: Symbol's value as variable is void: _c
.. I repeat, this is a bug. It should have returned 6.
> > Instead of giving me the value of _old-len (which was 3) it gave the
> > error message
> > Error: Symbol's value as variable is void: _old-len
> > .. This is a bug.
> Could be. Or could be that you were trying to use `_old-len` in
> a lexical context where there is no such variable.
_c is in the same lexical context as a and b, surely?
> > Just because a function doesn't use a particular argument (here
> I think the leading underscore is purely incidental and you'd get the
> same behavior with `beg` and `end`.
No, beg and end returned their values. I admit I'm speculating about the
leading underscore, but I still say there's a bug, somewhere here.
> Stefan
--
Alan Mackenzie (Nuremberg, Germany).
next prev parent reply other threads:[~2022-11-14 10:28 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-12 9:35 bug#59213: Emacs 29: Edebug fails to instrument a parameter whose name begins with _ Alan Mackenzie
2022-11-14 2:48 ` Michael Heerdegen
2022-11-14 3:53 ` Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors
2022-11-14 10:28 ` Alan Mackenzie [this message]
2022-11-14 12:50 ` Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors
2022-11-14 12:56 ` Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors
2023-02-10 18:51 ` Alan Mackenzie
2023-02-10 22:05 ` Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors
2023-02-11 7:26 ` Eli Zaretskii
2023-02-13 3:26 ` Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors
2023-02-13 12:54 ` Eli Zaretskii
2023-02-11 11:17 ` Alan Mackenzie
2023-02-14 21:47 ` Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors
2023-02-14 22:19 ` Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors
2023-02-18 18:08 ` Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors
2023-02-18 18:46 ` Alan Mackenzie
2023-02-20 22:21 ` Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors
2022-11-15 13:08 ` Eli Zaretskii
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=Y3IYTSTtOBZSRZ3z@ACM \
--to=acm@muc.de \
--cc=59213@debbugs.gnu.org \
--cc=monnier@iro.umontreal.ca \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this external index
https://git.savannah.gnu.org/cgit/emacs.git
https://git.savannah.gnu.org/cgit/emacs/org-mode.git
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.