01/02: self: Shrink the module search path of the 'guix' command.

[Ludovic Courtès]

civodul pushed a commit to branch master
in repository guix.

commit f2d0a2cf5c905abf816bef5d69364d28af5144ed
Author: Ludovic Courtès <address@hidden>
Date:   Mon Aug 27 22:17:12 2018 +0200

    self: Shrink the module search path of the 'guix' command.
    
    Previously we'd have lots of useless entries on the search paths, such
    as libtasn1, libidn2, zlib, gmp, etc. because they are propagated by
    gnutls.
    
    * guix/self.scm (guix-command)[source-directories, object-directories]:
    New variables.  Use them in the body of "guix-command".  Filter their
    items with 'file-exists?'.
---
 guix/self.scm | 24 ++++++++++++++----------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/guix/self.scm b/guix/self.scm
index 5ad644b..90649db 100644
--- a/guix/self.scm
+++ b/guix/self.scm
@@ -367,22 +367,26 @@ DOMAIN, a gettext domain."
                        guile (guile-version (effective-version)))
   "Return the 'guix' command such that it adds MODULES and DEPENDENCIES in its
 load path."
+  (define source-directories
+    (map (lambda (package)
+           (file-append package "/share/guile/site/"
+                        guile-version))
+         dependencies))
+
+  (define object-directories
+    (map (lambda (package)
+           (file-append package "/lib/guile/"
+                        guile-version "/site-ccache"))
+         dependencies))
+
   (program-file "guix-command"
                 #~(begin
                     (set! %load-path
-                      (append '#$(map (lambda (package)
-                                        (file-append package
-                                                     "/share/guile/site/"
-                                                     guile-version))
-                                      dependencies)
+                      (append (filter file-exists? '#$source-directories)
                               %load-path))
 
                     (set! %load-compiled-path
-                      (append '#$(map (lambda (package)
-                                        (file-append package "/lib/guile/"
-                                                     guile-version
-                                                     "/site-ccache"))
-                                      dependencies)
+                      (append (filter file-exists? '#$object-directories)
                               %load-compiled-path))
 
                     (set! %load-path (cons #$modules %load-path))