ui: Factorize `--version'.

* guix/ui.scm (show-version-and-exit): New procedure.
* guix-build.in (show-version): Remove.
  (%options)["version"]: Use `show-version-and-exit'.
* guix-download.in: Likewise.
* guix-package.in: Likewise.

1 files changed, 8 insertions, 0 deletions

diff --git a/guix/ui.scm b/guix/ui.scm
index cb78a21bd8..447c3a9a9f 100644
--- a/guix/ui.scm
+++ b/guix/ui.scm
@@ -19,12 +19,14 @@
 (define-module (guix ui)
   #:use-module (guix utils)
   #:use-module (guix store)
+  #:use-module (guix config)
   #:use-module (guix packages)
   #:use-module (srfi srfi-26)
   #:use-module (srfi srfi-34)
   #:export (_
             N_
             leave
+            show-version-and-exit
             call-with-error-handling
             with-error-handling))
 
@@ -46,6 +48,12 @@
     (format (current-error-port) fmt args ...)
     (exit 1)))
 
+(define* (show-version-and-exit #:optional (command (car (command-line))))
+  "Display version information for COMMAND and `(exit 0)'."
+  (simple-format #t "~a (~a) ~a~%"
+                 command %guix-package-name %guix-version)
+  (exit 0))
+
 (define (call-with-error-handling thunk)
   "Call THUNK within a user-friendly error handler."
   (guard (c ((package-input-error? c)