From: Drew Adams <drew.adams@oracle.com>
To: Dmitry Gutov <dgutov@yandex.ru>, Paul Eggert <eggert@cs.ucla.edu>
Cc: "Michael Heerdegen" <michael_heerdegen@web.de>,
"Mattias Engdegård" <mattiase@acm.org>,
ke.vigouroux@laposte.net, 40671@debbugs.gnu.org,
"Richard Stallman" <rms@gnu.org>
Subject: bug#40671: [DOC] modify literal objects
Date: Thu, 30 Apr 2020 22:15:53 -0700 (PDT) [thread overview]
Message-ID: <47664b27-687f-4d23-bc55-9f3faa7965a9@default> (raw)
In-Reply-To: <6cbe3c10-6d81-f2be-30d7-17096b3f3517@yandex.ru>
> >> You're _not_ using the language that's used for Common Lisp.
> > In what sense does the language differ? Here's a quote from CLtL2
> (page 115):
> >
> > "it is an error to destructively modify any object that appears as a
> constant
> > in executable code, whether within a 'quote' special form or as
> > a self-evaluating form."
>
> As Drew pointed out (and if I understood this correctly), the above
> specification leads to implementations that do raise an error when
> someone tried to modify such a value.
That's my understanding. I believe that wasn't
the case for CLTL(1) - there was no such promise
or requirement. And I think it's also not the
case for Elisp. Like CLTL(1), we should just
warn users about the gotcha, since there's no
protection from it.
To be clear, I'm no expert on CLTL2. I used
CL for years before that. The gotcha bit me
once, having modified the result of a quoted
list - and then someone explained what was
happening.
It's too easy for a newbie to think only in
terms of textual source code being interpreted.
It's easy not to realize, as Michael said, that
there's the Lisp reader, the interpreter, and
the byte-compiler, and each might get a chance
to handle a quoted list. And just how they did
so was not specified.
Presumably, a conformant CL implementation now
protects you from this gotcha.
next prev parent reply other threads:[~2020-05-01 5:15 UTC|newest]
Thread overview: 170+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-16 19:28 bug#40671: [DOC] modify literal objects Kevin Vigouroux via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-04-17 16:09 ` Mattias Engdegård
2020-04-17 16:37 ` Mattias Engdegård
2020-04-17 17:27 ` Eli Zaretskii
2020-04-18 20:10 ` Paul Eggert
2020-04-18 21:54 ` Drew Adams
2020-04-19 2:39 ` Noam Postavsky
2020-04-19 20:39 ` Paul Eggert
2020-04-19 21:01 ` Drew Adams
2020-04-19 21:16 ` Paul Eggert
2020-04-19 22:24 ` Drew Adams
2020-04-19 22:51 ` Paul Eggert
2020-04-20 5:32 ` Drew Adams
2020-04-22 17:36 ` Paul Eggert
2020-05-01 3:03 ` Dmitry Gutov
2020-05-01 5:16 ` Drew Adams
2020-05-01 21:46 ` Paul Eggert
2020-05-01 23:37 ` Dmitry Gutov
2020-04-19 2:26 ` Richard Stallman
2020-04-19 13:56 ` Eli Zaretskii
2020-04-19 16:59 ` Mattias Engdegård
2020-04-19 19:21 ` Eli Zaretskii
2020-04-19 21:02 ` Paul Eggert
2020-04-19 21:11 ` Drew Adams
2020-04-19 21:57 ` Michael Heerdegen
2020-04-19 22:41 ` Paul Eggert
2020-04-19 23:45 ` Michael Heerdegen
2020-04-20 0:24 ` Paul Eggert
2020-04-20 0:53 ` Michael Heerdegen
2020-04-20 3:23 ` Paul Eggert
2020-04-20 3:36 ` Michael Heerdegen
2020-04-22 6:30 ` Paul Eggert
2020-04-20 5:54 ` Drew Adams
2020-04-22 17:21 ` Paul Eggert
2020-04-23 0:49 ` Michael Heerdegen
2020-04-24 2:36 ` Richard Stallman
2020-04-24 15:08 ` Drew Adams
2020-04-25 1:58 ` Paul Eggert
2020-04-24 16:39 ` Mattias Engdegård
2020-04-24 16:46 ` Dmitry Gutov
2020-04-25 2:21 ` Paul Eggert
2020-04-25 2:40 ` Dmitry Gutov
2020-04-25 3:20 ` Paul Eggert
2020-04-25 19:30 ` Dmitry Gutov
2020-04-26 3:49 ` Paul Eggert
2020-04-26 14:03 ` Dmitry Gutov
2020-04-26 14:19 ` Eli Zaretskii
2020-04-26 14:34 ` Dmitry Gutov
2020-04-26 15:46 ` Eli Zaretskii
2020-04-26 16:02 ` Dmitry Gutov
2020-04-26 16:58 ` Eli Zaretskii
2020-04-26 17:39 ` Dmitry Gutov
2020-04-26 18:14 ` Eli Zaretskii
2020-04-26 18:32 ` Dmitry Gutov
2020-04-26 18:41 ` Eli Zaretskii
2020-04-26 18:53 ` Dmitry Gutov
2020-04-26 18:57 ` Paul Eggert
2020-04-26 19:22 ` Philipp Stephani
2020-04-26 20:14 ` Paul Eggert
2020-04-26 21:23 ` Dmitry Gutov
2020-04-26 23:13 ` Paul Eggert
2020-04-27 0:53 ` Dmitry Gutov
2020-04-27 1:49 ` Paul Eggert
2020-04-28 3:05 ` Dmitry Gutov
2020-04-28 8:17 ` Paul Eggert
2020-04-28 13:54 ` Dmitry Gutov
2020-04-28 17:59 ` Paul Eggert
2020-04-28 18:46 ` Dmitry Gutov
2020-04-28 19:20 ` Paul Eggert
2020-04-28 19:33 ` Dmitry Gutov
2020-04-28 20:09 ` Paul Eggert
2020-04-28 21:10 ` Dmitry Gutov
2020-04-28 23:10 ` Paul Eggert
2020-04-28 23:36 ` Dmitry Gutov
2020-04-28 23:53 ` Paul Eggert
2020-04-28 23:57 ` Dmitry Gutov
2020-04-28 23:53 ` Dmitry Gutov
2020-04-29 0:04 ` Paul Eggert
2020-04-29 0:14 ` Dmitry Gutov
2020-04-29 0:55 ` Drew Adams
2020-04-29 1:03 ` Dmitry Gutov
2020-04-29 1:15 ` Drew Adams
2020-04-29 1:27 ` Michael Heerdegen
2020-04-29 1:38 ` Paul Eggert
2020-04-29 4:36 ` Drew Adams
2020-04-29 16:18 ` Paul Eggert
2020-05-01 2:47 ` Richard Stallman
2020-05-01 6:23 ` Eli Zaretskii
2020-05-01 3:13 ` Dmitry Gutov
2020-05-01 5:15 ` Drew Adams [this message]
2020-05-01 21:40 ` Paul Eggert
2020-05-01 22:05 ` Drew Adams
2020-05-01 22:28 ` Paul Eggert
2020-05-02 1:07 ` Dmitry Gutov
2020-05-02 6:28 ` Paul Eggert
2020-05-02 15:42 ` Dmitry Gutov
2020-05-02 19:35 ` Paul Eggert
2020-05-03 1:30 ` Dmitry Gutov
2020-05-03 7:40 ` Paul Eggert
2020-05-03 16:44 ` Dmitry Gutov
2020-05-03 20:48 ` Paul Eggert
2020-05-03 22:17 ` Dmitry Gutov
2020-05-03 22:18 ` Dmitry Gutov
2020-05-03 22:39 ` Paul Eggert
2020-05-03 22:53 ` Dmitry Gutov
2020-05-03 23:10 ` Paul Eggert
2020-05-04 10:16 ` Dmitry Gutov
2020-05-04 17:52 ` Paul Eggert
2020-05-05 1:39 ` Dmitry Gutov
2020-05-05 6:09 ` Paul Eggert
2020-05-05 12:38 ` Dmitry Gutov
2020-05-09 6:10 ` Paul Eggert
2020-05-10 3:13 ` Dmitry Gutov
2020-05-10 13:34 ` Dmitry Gutov
2020-05-10 17:29 ` Paul Eggert
2020-05-11 0:00 ` Michael Heerdegen
2020-05-11 0:26 ` Dmitry Gutov
2020-05-11 1:47 ` Drew Adams
2020-05-11 1:54 ` Dmitry Gutov
2020-05-11 2:33 ` Drew Adams
2020-05-11 2:56 ` Michael Heerdegen
2020-05-11 4:21 ` Drew Adams
2020-05-11 4:51 ` Michael Heerdegen
2020-05-11 6:28 ` Paul Eggert
2020-05-11 13:57 ` Noam Postavsky
2020-05-11 22:36 ` Michael Heerdegen
2020-05-11 22:30 ` Michael Heerdegen
2020-05-12 3:20 ` Richard Stallman
2020-05-12 4:24 ` Michael Heerdegen
2020-05-13 3:57 ` Richard Stallman
2020-05-13 5:05 ` Michael Heerdegen
2020-05-14 5:14 ` Richard Stallman
[not found] ` <05BEF593-F16A-4DEE-98BC-653221F1F9EE@acm.org>
2020-05-17 0:11 ` Paul Eggert
2020-05-17 9:43 ` Mattias Engdegård
2020-05-17 16:38 ` Paul Eggert
2020-05-11 1:53 ` Paul Eggert
2020-05-11 3:18 ` Michael Heerdegen
2020-05-11 0:44 ` Dmitry Gutov
2020-05-11 1:57 ` Paul Eggert
2020-05-12 1:59 ` Dmitry Gutov
2020-05-17 1:28 ` Paul Eggert
2020-05-17 5:02 ` Michael Heerdegen
2020-05-17 16:34 ` Paul Eggert
2020-05-17 12:39 ` Dmitry Gutov
2020-05-17 16:21 ` Paul Eggert
2020-05-05 17:40 ` Drew Adams
2020-05-05 18:49 ` Dmitry Gutov
2020-05-05 19:26 ` Drew Adams
2020-05-05 20:48 ` Kevin Vigouroux via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-05-09 5:57 ` Paul Eggert
2020-04-28 21:18 ` Dmitry Gutov
2020-04-28 17:25 ` Drew Adams
2020-04-28 17:47 ` Paul Eggert
2020-04-29 0:32 ` Michael Heerdegen
2020-04-29 1:40 ` Paul Eggert
2020-04-29 4:40 ` Michael Heerdegen
2020-04-29 8:01 ` Eli Zaretskii
2020-04-29 16:36 ` Paul Eggert
2020-04-24 17:18 ` Drew Adams
2020-04-25 3:38 ` Richard Stallman
2020-04-25 18:26 ` Paul Eggert
2020-04-25 2:22 ` Paul Eggert
2020-04-25 6:00 ` Andreas Schwab
2020-04-25 18:23 ` Paul Eggert
2020-04-28 23:52 ` Michael Heerdegen
2020-04-21 1:25 ` Michael Heerdegen
2020-04-21 2:20 ` Paul Eggert
2020-04-20 6:02 ` Drew Adams
2020-04-19 20:45 ` Paul Eggert
2020-04-20 14:10 ` 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=47664b27-687f-4d23-bc55-9f3faa7965a9@default \
--to=drew.adams@oracle.com \
--cc=40671@debbugs.gnu.org \
--cc=dgutov@yandex.ru \
--cc=eggert@cs.ucla.edu \
--cc=ke.vigouroux@laposte.net \
--cc=mattiase@acm.org \
--cc=michael_heerdegen@web.de \
--cc=rms@gnu.org \
/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.