unofficial mirror of bug-gnu-emacs@gnu.org 
 help / color / mirror / code / Atom feed
From: "Mattias Engdegård" <mattiase@acm.org>
To: Stefan Kangas <stefan@marxist.se>
Cc: Michael Heerdegen <michael_heerdegen@web.de>,
	40972@debbugs.gnu.org, Shigeru Fukaya <shigeru.fukaya@gmail.com>
Subject: bug#40972: 27.0.91; assoc TESTFN's args reversed?
Date: Wed, 9 Sep 2020 16:46:43 +0200	[thread overview]
Message-ID: <25BD6B62-B196-44D5-8BB0-16F5A83D5922@acm.org> (raw)
In-Reply-To: <47D61E6B43780AC31D0B86@gmail.com>

> As Michael points out, the equality operation is symmetric and therefore by definition the order does not matter. We therefore cannot say if X=Y or Y=X is "more correct": they are equivalent.
> 
> In any case, I think it will cause more problems to switch the argument order at this point, since there might be code out there that relies on this (undocumented) behavior. So I'm closing this bug. 

It's quite possible that the current argument order was intended but never really documented. It's occasionally exploited (see image-converter--filter-formats). The asymmetry is stated more explicitly in the doc string and manual entry for assoc-default. Closing the bug is probably wisest.







  parent reply	other threads:[~2020-09-09 14:46 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-29 21:15 bug#40972: 27.0.91; assoc TESTFN's args reversed? Shigeru Fukaya
2020-04-29 23:30 ` Michael Heerdegen
2020-09-09 13:22   ` Stefan Kangas
2020-09-09 14:46 ` Mattias Engdegård [this message]
2020-09-09 15:18   ` Stefan Kangas
2020-09-09 15:51     ` Mattias Engdegård

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

  List information: https://www.gnu.org/software/emacs/

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=25BD6B62-B196-44D5-8BB0-16F5A83D5922@acm.org \
    --to=mattiase@acm.org \
    --cc=40972@debbugs.gnu.org \
    --cc=michael_heerdegen@web.de \
    --cc=shigeru.fukaya@gmail.com \
    --cc=stefan@marxist.se \
    /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 public inbox

	https://git.savannah.gnu.org/cgit/emacs.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).