From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: peder@klingenberg.no (Peder O. Klingenberg) Newsgroups: gmane.emacs.bugs Subject: bug#24221: 25.1.50; binding anonymous functions to keys cause help buffer navigation errors Date: Sun, 28 Aug 2016 22:07:57 +0200 Message-ID: References: NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1472414959 2565 195.159.176.226 (28 Aug 2016 20:09:19 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sun, 28 Aug 2016 20:09:19 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.1.50 (darwin) Cc: 24221@debbugs.gnu.org To: Zachary Kanfer Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Sun Aug 28 22:09:15 2016 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1be6OJ-0000Hm-CT for geb-bug-gnu-emacs@m.gmane.org; Sun, 28 Aug 2016 22:09:15 +0200 Original-Received: from localhost ([::1]:40780 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1be6OG-0008AI-Ty for geb-bug-gnu-emacs@m.gmane.org; Sun, 28 Aug 2016 16:09:12 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:59129) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1be6OB-0008A2-5I for bug-gnu-emacs@gnu.org; Sun, 28 Aug 2016 16:09:08 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1be6O6-0001Sa-UF for bug-gnu-emacs@gnu.org; Sun, 28 Aug 2016 16:09:06 -0400 Original-Received: from debbugs.gnu.org ([208.118.235.43]:45374) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1be6O6-0001SW-QY for bug-gnu-emacs@gnu.org; Sun, 28 Aug 2016 16:09:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1be6O5-0004Vj-T4 for bug-gnu-emacs@gnu.org; Sun, 28 Aug 2016 16:09:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: peder@klingenberg.no (Peder O. Klingenberg) Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sun, 28 Aug 2016 20:09:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 24221 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 24221-submit@debbugs.gnu.org id=B24221.147241489717280 (code B ref 24221); Sun, 28 Aug 2016 20:09:01 +0000 Original-Received: (at 24221) by debbugs.gnu.org; 28 Aug 2016 20:08:17 +0000 Original-Received: from localhost ([127.0.0.1]:43081 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1be6NM-0004Ue-Ud for submit@debbugs.gnu.org; Sun, 28 Aug 2016 16:08:17 -0400 Original-Received: from tarrant.klingenberg.no ([80.91.231.253]:37689) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1be6NL-0004UV-AB for 24221@debbugs.gnu.org; Sun, 28 Aug 2016 16:08:15 -0400 Original-Received: from cm-84.211.197.29.getinternet.no ([84.211.197.29] helo=modesty.getinternet.no) by tarrant.klingenberg.no with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.80) (envelope-from ) id 1be6N9-0002AE-7y; Sun, 28 Aug 2016 22:08:09 +0200 Original-Received: by modesty.getinternet.no (Postfix, from userid 502) id C1A2514D24C2; Sun, 28 Aug 2016 22:07:57 +0200 (CEST) In-Reply-To: (Zachary Kanfer's message of "Sat, 13 Aug 2016 20:59:37 -0400") X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 208.118.235.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.org gmane.emacs.bugs:122750 Archived-At: Zachary Kanfer writes: > emacs -Q > > Evaluate this code: > > (global-set-key (kbd "C-c l") (lambda () (interactive) (insert "This > messes up the help buffer somehow."))) > > Then open up a help buffer for that function: > > C-h k C-c l > > And a help buffer for something else: > > C-h k a > > Then, in the help buffer, go to the bottom, and try to select the > "[back]" link. I get an error: "user-error: You didn=E2=80=99t specify a = function > symbol". If I try again, I get a different error: "apply: Symbol=E2=80=99s > function definition is void: nil". These errors happen whether I've > select the link with pressing Enter on the keyboard or by clicking the > mouse. I can confirm this. Here's what I think is happening: `describe-key' (C-h k) finds your lambda expression when it calls `key-binding'. It then pushes this lambda on the help-xref-stack as an argument to `describe-function'. But `describe-function' doesn't know what to do with a lamda expression, and gives you that "You didn't specify a function symbol" message when the xref stack is popped and `describe-function' is called. I don't know what the best fix would be - fix the xref setup in `describe-key' or teach `describe-function' to do something useful with a lambda expression.