From: Jean Louis <bugs@gnu.support>
To: Help GNU Emacs <help-gnu-emacs@gnu.org>
Subject: Is it possible to save undo state in file and reload again?
Date: Fri, 06 Jan 2023 18:24:41 +0300 [thread overview]
Message-ID: <0357584ce5b79f1e9f0c303f22901b06.support1@rcdrun.com> (raw)
There must exist some "undo" state in Emacs for {C-x u} to work,
right?
Is it maybe the contents of variable `pending-undo-list'?
I have tried saving it this way:
(defun data-to-file (data file)
"PRIN1 Emacs Lisp DATA to FILE"
(string-to-file-force (prin1-to-string data) file))
(defun data-from-file (file)
"Reads and returns Emacs Lisp data from FILE"
(condition-case nil
(car (read-from-string
(file-to-string file)))
(error nil)))
(data-to-file pending-undo-list "pul") ➜ "pul"
(file-to-string "pul") works and I can see what is inside.
But then my function `data-from-file' can't handle it:
(data-from-file "pul")
because I get this error
(read-from-string (file-to-string "pul"))
eval: Invalid read syntax: "#"
How can I save it in file and read from file with that read syntax
"#"? It should be somehow possible.
When editing database objects I would try to capture the undo state
and at any new editing to reload the undo state.
--
Jean
Take action in Free Software Foundation campaigns:
https://www.fsf.org/campaigns
In support of Richard M. Stallman
https://stallmansupport.org/
reply other threads:[~2023-01-06 15:24 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=0357584ce5b79f1e9f0c303f22901b06.support1@rcdrun.com \
--to=bugs@gnu.support \
--cc=help-gnu-emacs@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.
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).