Re: Using the Guile json module in a gexp

[ludo@gnu.org (Ludovic Courtès)]

Hello!

Christopher Baines <mail@cbaines.net> skribis:

> So I'm having some trouble using the Guile json module in a gexp.
> I've added (with-imported-modules '((json)) ...), and the
> module-import-compiled builder crashes.
>
> Backtrace:
>            4 (primitive-load "/gnu/store/35zv0m9wwd2nz3agyywv09d3k5v?")
> In srfi/srfi-1.scm:
>     640:9  3 (for-each #<procedure c10700 at ice-9/eval.scm:333:13 ?> ?)
> In ice-9/eval.scm:
>    245:16  2 (_ #(#(#<directory (guix build utils) 83f6e0> "/gn?") #))
> In ice-9/boot-9.scm:
>   1519:24  1 (_ "./json.scm")
> In unknown file:
>            0 (stat "./json.scm" #<undefined>)
>
> ERROR: In procedure stat:
> ERROR: In procedure stat: No such file or directory: "./json.scm"

This would have the effect of importing the (json) module of the host
environment into the build environment, which is not desirable for a
couple of reasons:

  1. It would require having Guile-JSON installed in the host
     environment, and the right version of it.

  2. It would hinder reproducibility since different users may have
     different Guile-JSON variants installed on the host side.

To overcome this, you have to do like (guix scripts package) does:

  #~(begin
      (add-to-load-path #$(file-append guile-json
                                       "/share/guile/site/"
                                       (effective-version)))
      …)

It would be nice to simplify this somehow, though.

HTH!

Ludo’.