From 6cd1059340758669a7d98c4611f5d418b51899f2 Mon Sep 17 00:00:00 2001 From: Ludovic Courtès Date: Tue, 17 Jan 2017 22:58:37 +0100 Subject: doc: Add '--manifest' example using 'specification->package+output'. * doc/guix.texi (Invoking guix package): Add --manifest example using 'specification->package+output'. --- doc/guix.texi | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/doc/guix.texi b/doc/guix.texi index bf9dbaa726..a212666af0 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -1685,6 +1685,20 @@ of packages: (list guile-2.0 "debug"))) @end example +@findex specification->package+output +In this example we have to know which modules define the @code{emacs} +and @code{guile-2.0} variables to provide the right +@code{use-package-modules} line, which can be cumbersome. We can +instead provide regular package specifications and let +@code{specification->package-output} look up the corresponding package +objects, like this: + +@example +(packages->manifest + (map (compose list specification->package+output) + '("emacs" "guile@@2.0" "guile@@2.0:debug"))) +@end example + @item --roll-back @cindex rolling back @cindex undoing transactions -- cgit v1.2.3