From: Phil Sainty <psainty@orcon.net.nz>
To: Qiantan Hong <qthong@stanford.edu>
Cc: emacs-devel@gnu.org
Subject: Re: PACKAGE-FEATURES, and hot update of Emacs packages
Date: Sun, 28 Nov 2021 20:22:01 +1300 [thread overview]
Message-ID: <1b4dbbf030bcb92ea47c46efa4c246f3@webmail.orcon.net.nz> (raw)
In-Reply-To: <A775C648-D90E-4A19-837F-57B49079E5BE@stanford.edu>
On 2021-11-28 09:36, Qiantan Hong wrote:
> This require the user to reload the file.
Yes indeed. Or rather, it *supports* them reloading the file.
> Currently if the old package is not unloaded, the feature is still
> present and (require p) does nothing.
Certainly `require' won't do anything, but nothing prevents you from
using `load-library' for for the same list of libraries that you were
planning to unload.
You can't be certain that's going to be safe, though. Reloading a
library is expected to be safe when the code is unchanged, but there's
no requirement that I'm aware of to support loading new code over the
old code -- that will often be fine in practice, but there's loads of
scope for it not to be.
And as before, I don't think it's valid to unload things (even if you
could be confident that everything supported being unloaded) because
you destroy the configuration.
I can't think of a way to reliably do what you're suggesting in the
general case. Each approach will work in certain circumstances, but
I don't think any approach is *generally* reliable.
Libraries could probably declare themselves as supporting reloading
if the author believed that to be the case, and you could have an
automated reload sequence if everything claimed to support it.
-Phil
next prev parent reply other threads:[~2021-11-28 7:22 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-27 9:31 PACKAGE-FEATURES, and hot update of Emacs packages Qiantan Hong
2021-11-27 10:09 ` Eli Zaretskii
2021-11-27 10:18 ` Qiantan Hong
2021-11-27 10:20 ` Qiantan Hong
2021-11-27 12:16 ` Phil Sainty
2021-11-27 13:30 ` Phil Sainty
2021-11-27 20:36 ` Qiantan Hong
2021-11-28 7:22 ` Phil Sainty [this message]
2021-11-28 7:51 ` Qiantan Hong
2021-11-28 1:04 ` Tim Cross
2021-11-28 4:23 ` Phil Sainty
2021-11-28 5:12 ` Stefan Monnier
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=1b4dbbf030bcb92ea47c46efa4c246f3@webmail.orcon.net.nz \
--to=psainty@orcon.net.nz \
--cc=emacs-devel@gnu.org \
--cc=qthong@stanford.edu \
/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).