build-system: Factorize the list of modules imported on the build side.

* guix/build-system/gnu.scm (%default-modules): Rename to...
  (%gnu-build-system-modules): ... this.
  (%default-modules): New variable.
  (dist-package, gnu-build): Use %GNU-BUILD-SYSTEM-MODULES for
  #:imported-modules.
  (gnu-cross-build): Likewise, and use %DEFAULT-MODULES for #:modules.
* guix/build-system/cmake.scm (%cmake-build-system-modules): New
  variable.
  (cmake-build): Use it for #:imported-modules.
* guix/build-system/glib-or-gtk.scm (%default-imported-modules): Rename
  to...
  (%glib-or-gtk-build-system-modules): ... this.  Refer to
  %GNU-BUILD-SYSTEM-MODULES.  Adjust uses.
* guix/build-system/perl.scm (%perl-build-system-modules): New
  variable.
  (perl-build): Use it for #:imported-modules.
* guix/build-system/python.scm (%python-build-system-modules): New
  variable.
  (python-build): Use it for #:imported-modules.
* guix/build-system/ruby.scm (%ruby-build-system-modules): New variable.
  (ruby-build): Use it for #:imported-modules.
* guix/build-system/waf.scm (%waf-build-system-modules): New variable.
  (waf-build): Use it for #:imported-modules.

1 files changed, 9 insertions, 5 deletions

diff --git a/guix/build-system/perl.scm b/guix/build-system/perl.scm
index e0f86438a8..7833153676 100644
--- a/guix/build-system/perl.scm
+++ b/guix/build-system/perl.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2013, 2014 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2013, 2014, 2015 Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -24,7 +24,8 @@
   #:use-module (guix build-system gnu)
   #:use-module (guix packages)
   #:use-module (ice-9 match)
-  #:export (perl-build
+  #:export (%perl-build-system-modules
+            perl-build
             perl-build-system))
 
 ;; Commentary:
@@ -35,6 +36,11 @@
 ;;
 ;; Code:
 
+(define %perl-build-system-modules
+  ;; Build-side modules imported by default.
+  `((guix build perl-build-system)
+    ,@%gnu-build-system-modules))
+
 (define (default-perl)
   "Return the default Perl package."
 
@@ -83,9 +89,7 @@
                      (outputs '("out"))
                      (system (%current-system))
                      (guile #f)
-                     (imported-modules '((guix build perl-build-system)
-                                         (guix build gnu-build-system)
-                                         (guix build utils)))
+                     (imported-modules %perl-build-system-modules)
                      (modules '((guix build perl-build-system)
                                 (guix build utils))))
   "Build SOURCE using PERL, and with INPUTS.  This assumes that SOURCE