Re: [PATCH] emacs: devel: Highlight 'modify-phases' keywords.

[ludo@gnu.org (Ludovic Courtès)]

Alex Kost <alezost@gmail.com> skribis:

>> ;; For Guix g-expressions.
>> (font-lock-add-keywords 'scheme-mode
>> 			'(("#~" . font-lock-keyword-face)
>> 			  ("#\\$" . font-lock-keyword-face)
>> 			  ("#\\+" . font-lock-keyword-face)))
>
> Great, what about the attached patch for adding these ones?

Looks good.

>> Similarly .dir-locals.el has ‘modify-syntax-entry’ stuff for gexps that
>> could maybe go to guix-devel.el?
>
> Yes, they could.  So as you mention it, there is another thing I would
> like to add — complex indentation rules.  Specifically, inherited
> packages are automatically indented like this:
>
> (package (inherit foo)
>          (name "foo")
>          ...)
>
> or this:
>
> (package
>   (inherit foo)
>   (name "foo")
>   ...)
>
> while we want it to be:
>
> (package (inherit foo)
>   (name "foo")
>   ...)
>
> The following code may be used to handle this indentation:
>
> (defun guix-devel-package-indent (state indent-point normal-indent)
>   (let ((count (if (and (ignore-errors (down-list) t)
>                         (looking-at "inherit\\>"))
>                    1
>                  0)))
>     (lisp-indent-specform count state indent-point normal-indent)))
>
> (put 'package 'scheme-indent-function 'guix-devel-package-indent)

Nice!  I like it, I think it would be a nice addition.

At the same time I wonder if defining sophisticated indentation rules is
a good idea in general.  (Though this one was already defined anyway.)

> But it wouldn't work reliably because of ".dir-locals.el", as
> 'scheme-indent-function' property will be overridden every time a scheme
> file from git repo is visited.  So my proposition is: what about moving
> all indentation rules from ".dir-locals.el" to "emacs/guix-devel.el"?
> So 'guix-devel-mode' will be responsible for all indenting, highlighting
> and other guix-specific things.  WDYT?

Good question.  .dir-locals.el includes a bunch of internal rules that
do not make sense outside.

For those who do make sense outside, such as rules for ‘package’, I
think having them in .dir-locals.el has the advantage that Emacs users
cannot escape them inadvertently.  With guix-devel.el, there’s a greater
chance of people not loading it.

Unless .dir-locals.el has something like:

   (eval . (load "emacs/guix-devel.el")) ;…

?

Thoughts?

> From 13ebd00178d1f6139da4c1f76a2e358935ce16f0 Mon Sep 17 00:00:00 2001
> From: Alex Kost <alezost@gmail.com>
> Date: Sat, 26 Sep 2015 22:42:07 +0300
> Subject: [PATCH] emacs: devel: Highlight gexp symbols.
> MIME-Version: 1.0
> Content-Type: text/plain; charset=UTF-8
> Content-Transfer-Encoding: 8bit
>
> Suggested by Ludovic Courtès <ludo@gnu.org>.
>
> * emacs/guix-devel.el (guix-devel-gexp-symbol): New face.
>   (guix-devel-font-lock-keywords): Adjust to handle gexp symbols.

OK.

Thanks,
Ludo’.