From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Alan Mackenzie Newsgroups: gmane.emacs.bugs Subject: bug#66750: Unhelpful text in C-h v for variables with a lambda form as value Date: Sat, 28 Oct 2023 18:59:14 +0000 Message-ID: References: <838r7md237.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="33113"; mail-complaints-to="usenet@ciao.gmane.io" Cc: acorallo@gnu.org, 66750@debbugs.gnu.org, monnier@iro.umontreal.ca, acm@muc.de, stefankangas@gmail.com To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Sat Oct 28 20:59:45 2023 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1qwoXA-0008S8-UT for geb-bug-gnu-emacs@m.gmane-mx.org; Sat, 28 Oct 2023 20:59:44 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qwoWy-0004Zq-OZ; Sat, 28 Oct 2023 14:59:32 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qwoWx-0004Zi-9W for bug-gnu-emacs@gnu.org; Sat, 28 Oct 2023 14:59:31 -0400 Original-Received: from debbugs.gnu.org ([2001:470:142:5::43]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1qwoWx-0004wL-1G for bug-gnu-emacs@gnu.org; Sat, 28 Oct 2023 14:59:31 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1qwoXS-0006AB-Qm for bug-gnu-emacs@gnu.org; Sat, 28 Oct 2023 15:00:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Alan Mackenzie Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sat, 28 Oct 2023 19:00:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 66750 X-GNU-PR-Package: emacs Original-Received: via spool by 66750-submit@debbugs.gnu.org id=B66750.169851959623654 (code B ref 66750); Sat, 28 Oct 2023 19:00:02 +0000 Original-Received: (at 66750) by debbugs.gnu.org; 28 Oct 2023 18:59:56 +0000 Original-Received: from localhost ([127.0.0.1]:39569 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1qwoXM-00069R-9J for submit@debbugs.gnu.org; Sat, 28 Oct 2023 14:59:56 -0400 Original-Received: from mail.muc.de ([193.149.48.3]:60225) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1qwoXJ-00069C-0z for 66750@debbugs.gnu.org; Sat, 28 Oct 2023 14:59:54 -0400 Original-Received: (qmail 48419 invoked by uid 3782); 28 Oct 2023 20:59:15 +0200 Original-Received: from acm.muc.de (p4fe15319.dip0.t-ipconnect.de [79.225.83.25]) (using STARTTLS) by colin.muc.de (tmda-ofmipd) with ESMTP; Sat, 28 Oct 2023 20:59:14 +0200 Original-Received: (qmail 20491 invoked by uid 1000); 28 Oct 2023 18:59:14 -0000 Content-Disposition: inline In-Reply-To: <838r7md237.fsf@gnu.org> X-Submission-Agent: TMDA/1.3.x (Ph3nix) X-Primary-Address: acm@muc.de X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list 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-mx.org@gnu.org Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.bugs:273465 Archived-At: Hello, Eli. On Sat, Oct 28, 2023 at 21:38:36 +0300, Eli Zaretskii wrote: > > Cc: 66750@debbugs.gnu.org, Andrea Corallo , > > Stefan Kangas , acm@muc.de > > Date: Sat, 28 Oct 2023 18:17:04 +0000 > > From: Alan Mackenzie > > > but that's 127kB, so ... could [you] briefly describe the overall design > > > (IOW, how it's seen by ELisp programmers, byte-compiler hackers, and > > > ELisp users)? > > Certainly. Each lambda expression has (usually) a defun within which it > > is defined. Sometimes it's in a defvar, or defcustom. That > > @dfn{defining symbol} is recorded in the lambda form in one of three > > ways: > > (i) For a cons form, it's (cadr form), a new field inserted between the > > symbol `lambda' and the argument list. > > (ii) For a byte-compiled form, it's (aref form 5), this new field going > > after the doc string and before any interactive form in the compiled > > form. > > (iii) For a native-compiled subr it's (subr-native-defining-symbol > > subr), a function defined in data.c. It accesses a new field in struct > > Lisp_Subr called defining_symbol. > > There are lots of detailed changes in eval.c and bytecomp.el (and > > friends). Also the macro `lambda' in subr.el has been amended to insert > > the current global defining-symbol if there isn't already a non-nil > > symbol in that position. cl-print-object/compiled-function has been > > amended to print the defining-symbol, and there is a new > > cl-print-object/subr which does the same. > > The intention is that compiled objects from earlier Emacsen can still be > > loaded and run by feature/named-lambdas, just without the defining > > symbols (which will appear to be nil). > > > Also, what other approaches have you considered/tried and what were the > > > problems you've encountered, if any? > > feature/named-lambdas was originally intended for use in backtraces. > > For the current bug, I've considered individually replacing each lambda > > with a named defun, so that C-h v will show that name rather than an > > unhelpful byte/native compiled anonymous function. That would be a lot > > of work - my scripting found 63 defcustoms set to lambdas, 29 uses in > > doc strings, and 215 suspicious occurrences with ordinary variables > > (quite a few of which will be harmless). Amending all these (I guess > > around 200 lambdas) would probably be too much work. > Thanks. However, now I'm confused: what exactly does this feature > give us, if it doesn't handle all the lambdas in the Emacs tree and > (AFAIU) will not affect lambdas in third-party packages? Which > lambdas will now have a defining symbol, and which will not? It will handle all the lambdas in the Emacs tree. Each of them will get a defining-symbol set. Also third-party packages with lambdas will also get defining-symbols, provided they are compiled with feature/named-lambdas. It's just that .elc's/.eln's built with, say, Emacs-29 will continue to be loadable and runnable, but obviously without the defining symbol facility for those lambdas. -- Alan Mackenzie (Nuremberg, Germany).