6.3.2 Ludovic Courtès’s explore.scm program

The explore.scm script can then be modified as follows to have it work as a Guix extension rather than a script.

(→ 9 min 13 s into Simon Tournier presentation)

• removing the shebang call to guile

  -#!/bin/sh
  -exec "${GUILE:-guile}" -e "(@ (explore) guix-explore)" -s "$0" "$@"
  -!#
  

• replacing the module declaration with appropriate path/name

  -(define-module (explore)
  +(define-module (guix extensions explore)
  

• adding the module guix scripts to the use-module list

  …
  

   #:use-module (guix ui)
  + #:use-module (guix scripts)
   #:use-module (guix store)
  

  …
  

• modifying the guix-explore definition

  -(define (guix-explore args)
  +(define-command (guix-explore . args)
  + (category extension)
  + (synopsis ``explore your service'')
  (define %user-module @dots{}
  

  …
  

Note on the path to the script: [It seems that] to be used as a guix extension, Guix requires a script to live under a “[/…]/guix/extensions[/…]/<module-name>.scm” tree structure with the corresponding module declaration (define-module (guix extensions […] <module-name>) ….

This will work :

$ pwd
~/tmp/10-years-of-guix/guix/extensions/test
$ head -1 hello.scm
(define-module (guix extensions test hello)

… while this won’t work :

$ pwd
~/tmp/10-years-of-guix/guix/test
$ head -1 hello.scm
(define-module (guix test hello)

… nor this :

$ pwd
~/tmp/10-years-of-guix/nono/
$ head -1 hello.scm
(define-module (nono hello)

lauching

Note: explore produces a visual and interactive representation of the services used in a OS declaration. The user has to provide a path to the OS configuration file to explore.

All set, explore can now be used as a Guix extension like so :

$ export GUIX_EXTENSIONS_PATH=/path/to/guix/extensions
$ guix explore -- /path/to/configure.scm