From: ken <gebser@mousecar.com>
To: "Pascal J. Bourguignon" <pjb@informatimago.com>
Cc: help-gnu-emacs@gnu.org
Subject: Re: re-loading an elisp file
Date: Sat, 05 Mar 2011 11:46:09 -0500 [thread overview]
Message-ID: <4D7268D1.9000800@mousecar.com> (raw)
In-Reply-To: <87bp1ptwn6.fsf@kuiper.lan.informatimago.com>
On 03/05/2011 10:27 AM Pascal J. Bourguignon wrote:
> ken <gebser@mousecar.com> writes:
>
>> Is there a way, when reloading an elisp file, to have it examine (and
>> reload new) values of variables?
>
> There's a reason it's done: if you've painfully customized a module, you
> wouldn't want all your settings to be reset to default just because you
> reload its sources.
That's what I *am* doing-- *quite* and unnecessarily painfully
customizing a module-- and I *do* want variables to be re-initialized.
>
> So defvar is defined to set the value of the variable only if the
> variable is not already defined.
Then the name of the function should be called
"load-everything-except-variables". The "load" and
"eval-current-buffer" functions should do what their names say.
>
>
> In Common Lisp, there's also a defparameter macro that always sets the
> value of the variable. But of course, you wouldn't do that for
> customization variables, or for variables storing important state (eg. a
> database).
Are you saying I need to switch from elisp to common lisp or make a call
to common lisp just to change the value of a variable?
>
>
> So you may put:
>
> (defmacro defconstant (symbol initvalue &optional docstring)
> `(defconst ,symbol ,initvalue ,docstring))
>
> (defmacro defparameter (symbol &optional initvalue docstring)
> `(progn
> (defvar ,symbol nil ,docstring)
> (setq ,symbol ,initvalue)))
>
> in your ~/.emacs and use defparameter instead of defvar in some cases.
> But in general you don't want to.
So I need to put all this code in my ~/.emacs (and then of course
re-initialize ~/.emacs) whenever I need to re-initialize one variable?
But then wouldn't I need to take this code back out and re-initialize
~/.emacs again when I don't want to change the value of a variable?
I think it would be simpler and easier just to reboot all of emacs. But
quitting-and-restarting emacs seems like a radical procedure just to
re-initialize one variable.
>
>
> What you may do, is to provide a reset command to reinitialize the state
> of your module.
I was hoping I wouldn't have to write that code myself... I was
thinking that elisp should have a way to re-initialize a variable in a
module. That was really the point of my original post.
next prev parent reply other threads:[~2011-03-05 16:46 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <mailman.6.1299338195.13665.help-gnu-emacs@gnu.org>
2011-03-05 15:27 ` re-loading an elisp file Pascal J. Bourguignon
2011-03-05 16:46 ` ken [this message]
[not found] ` <mailman.18.1299343589.13665.help-gnu-emacs@gnu.org>
2011-03-05 17:41 ` Johan Bockgård
2011-03-05 23:09 ` ken
2011-03-05 22:17 ` Tim X
2011-03-05 23:21 ` PJ Weisberg
[not found] ` <mailman.3.1299367324.22865.help-gnu-emacs@gnu.org>
2011-03-06 0:05 ` Tim X
2011-03-06 5:32 ` rusi
2011-03-06 8:36 ` Le Wang
2011-03-08 1:18 ` Kevin Rodgers
[not found] ` <mailman.0.1299547100.4111.help-gnu-emacs@gnu.org>
2011-03-08 1:57 ` rusi
2011-03-08 2:01 ` rusi
2011-03-24 18:02 ` David Combs
2011-03-25 6:39 ` Tim X
2011-03-25 6:51 ` David Kastrup
2011-03-25 8:45 ` Jambunathan K
2011-03-25 22:23 ` Tim X
[not found] ` <mailman.2.1301064125.24725.help-gnu-emacs@gnu.org>
2011-03-25 23:01 ` Tim X
2011-03-26 4:25 ` Jambunathan K
[not found] ` <mailman.0.1301164236.2084.help-gnu-emacs@gnu.org>
2011-03-26 22:49 ` Tim X
2011-03-05 15:16 ken
2011-03-05 15:54 ` Drew Adams
2011-03-05 17:13 ` ken
2011-03-05 18:06 ` Drew Adams
2011-03-05 18:11 ` Drew Adams
2011-03-05 23:36 ` ken
2011-03-06 2:08 ` PJ Weisberg
[not found] ` <mailman.22.1299377327.22865.help-gnu-emacs@gnu.org>
2011-03-24 18:31 ` David Combs
2011-03-24 18:57 ` Drew Adams
[not found] ` <mailman.4.1299348453.24947.help-gnu-emacs@gnu.org>
2011-03-24 18:24 ` David Combs
2011-03-24 19:09 ` Drew Adams
[not found] ` <mailman.0.1299345251.24947.help-gnu-emacs@gnu.org>
2011-03-05 22:25 ` Tim X
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=4D7268D1.9000800@mousecar.com \
--to=gebser@mousecar.com \
--cc=help-gnu-emacs@gnu.org \
--cc=pjb@informatimago.com \
/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).