GNU bug report logs - #57003
28.1.90; Can local variables be loaded before loading major mode?

Previous Next

Full log

View this message in rfc822 format

From: Ihor Radchenko <yantar92 <at> gmail.com>
To: Lars Ingebrigtsen <larsi <at> gnus.org>
Cc: 57003 <at> debbugs.gnu.org
Subject: bug#57003: 28.1.90; Can local variables be loaded before loading major mode?
Date: Sun, 07 Aug 2022 21:52:33 +0800

Lars Ingebrigtsen <larsi <at> gnus.org> writes:

> Ihor Radchenko <yantar92 <at> gmail.com> writes:
>
>> Agree. However, the file-local variables specifically are not equivalent
>> to the mode hooks. File/directory-local variables can be set on
>> per-file/per-project basis, which is much more convenient compared to
>> explicitly defining a global hook.
>
> I think you can say something like
>
> (eval . (org-startup-folded-mode))
>
> to your .dir-locals (etc) to achieve this.  (And then you have to add
> that to `safe-local-eval-forms' to avoid getting prompted, but Org could
> do that in general.  And, of course, add this functionality as a minor
> mode instead of just a variable.)

I do not think that it is a good idea.

1. Having a need to do the eval is not expected by users.
2. Allowing eval is not safe compared to setting variables. Your
   suggestion about `safe-local-eval-forms' will not work well because
   even in your example it is not just about running
   (org-startup-folded-mode); org-startup-folded has 7 allowed values -
   marking each (org-startup-folded-mode value) form as safe sounds
   awkward.
3. org-startup-folded is just an example. We have numerous variables
   like this. I can recall at least several dozens without looking into
   source code. Creating a minor mode for each and every single possible
   variable like this is not maintainable. We will certainly forget
   creating dedicated modes when adding similar variables in future.
4. We have a somewhat similar approach in org-link settings - each link
   type is activated by evaluating a sexp. The result is slow Org
   startup time.

   If we implement per-file settings like you suggested, each setting
   will require partial re-evaluation of (org-mode). 
   A handful of settings like you suggested will easily degrade Org
   startup time by an order of magnitude.

Best,
Ihor

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.