Re: [PATCH] gnu: emacs-pdf-tools: Add missing input.

[ludo@gnu.org (Ludovic Courtès)]

Alex Kost <alezost@gmail.com> skribis:

> The bottom line of the following text is the question: Is it possible to
> combine 2 (or more) build systems for building a package?

Sure!

> I did a little experiment: I thought maybe it could be possible just to
> pick some build phases from (guix build emacs-build-system), so I added
> this module to #:modules and #:imported-modules and added phases like
> this:
>
>   (modify-phases %standard-phases
>     ;; ...
>     (add-after 'build 'emacs-build
>       (@@ (guix build emacs-build-system) build))
>     (add-after 'install 'emacs-install
>       (@@ (guix build emacs-build-system) install)))
>
> The package was built successfully, but the result was not good, because
> both gnu-build-system and emacs-build-system import %standard-phases :-)

You mean “export”?

I think you can always add a renamer upon import, using something like:

  (package
    ;; …
    (arguments
     `(#:imported-modules ((guix build emacs-build-system)
                           ,%gnu-build-system-modules)
       #:modules (((guix build emacs-build-system) #:prefix emacs:)
                  ,%gnu-build-system-modules)

       #:phases (modify-phases %standard-phases   ;from gnu-build-system
                  (add-before 'build 'emacs-build
                     (assoc-ref emacs:%standard-phases 'build))
                  ;; …
                  ))))

Would it work for you?

> From 5692ba83371fea16a34ff20d1f5d743f05173348 Mon Sep 17 00:00:00 2001
> From: Alex Kost <alezost@gmail.com>
> Date: Fri, 11 Mar 2016 11:34:20 +0300
> Subject: [PATCH] gnu: emacs-pdf-tools: Add missing input.
>
> This is a followup to commit eccd0b57a1f05b3caca28604f4d2c06556e2fe05.
>
> * gnu/packages/emacs.scm (emacs-pdf-tools)[propagated-inputs]: Add
> 'let-alist'.
> [arguments]: Adjust 'install-lisp' phase to compile pdf-tools using
> let-alist library.

Otherwise the patch LGTM.

Ludo’.