GNU bug report logs - #77612
[PATCH] (eieio-backward-compatibility): Change default to new `warn` value

Previous Next

To reply to this bug, email your comments to 77612 AT debbugs.gnu.org.

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

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

From: Stefan Monnier <monnier <at> iro.umontreal.ca>
To: bug-gnu-emacs <at> gnu.org
Subject: [PATCH] (eieio-backward-compatibility): Change default to new `warn`
 value
Date: Mon, 07 Apr 2025 13:29:35 -0400

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

Tags: patch

See commit message below.  I also encourage everyone to set
`eieio-backward-compatibility` to nil in their `.emacs`.


        Stefan

 In GNU Emacs 31.0.50 (build 2, i686-pc-linux-gnu, GTK+ Version 3.24.48,
 cairo version 1.18.2) of 2025-03-15 built on alfajor
Repository revision: 4a378e3b325ff3cb84307a2ff4d05ab9ffe24905
Repository branch: work
Windowing system distributor 'The X.Org Foundation', version 11.0.12101015
System Description: Debian GNU/Linux trixie/sid

Configured using:
 'configure -C --enable-checking --enable-check-lisp-object-type --with-modules --with-cairo --with-tiff=ifavailable
 'CFLAGS=-Wall -g3 -Og -Wno-pointer-sign'
 PKG_CONFIG_PATH=/home/monnier/lib/pkgconfig'

[0001-eieio-backward-compatibility-Change-default-to-new-w.patch (text/patch, attachment)]

Message #8 received at 77612 <at> debbugs.gnu.org (full text, mbox):

From: Stefan Monnier <monnier <at> iro.umontreal.ca>
To: 77612 <at> debbugs.gnu.org
Cc: "Eric M. Ludlam" <zappo <at> gnu.org>
Subject: Re: bug#77612: [PATCH] (eieio-backward-compatibility): Change
 default to new `warn` value
Date: Mon, 07 Apr 2025 18:36:19 -0400

> `eieio-backward-compatibility` controls compatibility with
> features declared obsolete since Emacs-25.  I'm not sure
> we're ready to remove support for those features (i.e. to set
> `eieio-backward-compatibility` to nil), so instead I suggest
> to make uses of those features emit warnings not only at
> compile-time but also at run-time.

I forgot to add the same treatment for the (ab)use of initargs as slot
names (also deprecated since Emacs-25), so I'd suggest adding the patch
below to the previous one.


        Stefan


diff --git a/lisp/emacs-lisp/eieio-core.el b/lisp/emacs-lisp/eieio-core.el
index 7d0fd643056..d608517e671 100644
--- a/lisp/emacs-lisp/eieio-core.el
+++ b/lisp/emacs-lisp/eieio-core.el
@@ -913,12 +913,15 @@
   (let* ((fsi (gethash slot (cl--class-index-table class))))
     (if (integerp fsi)
         fsi
+      (when eieio-backward-compatibility
       (let ((fn (eieio--initarg-to-attribute class slot)))
-	(if fn
+	  (when fn
+            (when (eq eieio-backward-compatibility 'warn)
+              (message "Accessing slot `%S' via obsolete initarg name `%S'"
+                       fn slot))
             ;; Accessing a slot via its :initarg is accepted by EIEIO
             ;; (but not CLOS) but is a bad idea (for one: it's slower).
-            (eieio--slot-name-index class fn)
-          nil)))))
+            (eieio--slot-name-index class fn)))))))
 
 (defun eieio--class-slot-name-index (class slot)
   "In CLASS find the index of the named SLOT.

Previous Next

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