01/02: news: Add entry for deep graph rewriting.

[guix-commits]

civodul pushed a commit to branch master
in repository guix.

commit db17af70f65359bb3eece101a889730d4f106171
Author: Ludovic Courtès <ludo@gnu.org>
AuthorDate: Sun Sep 27 23:10:47 2020 +0200

    news: Add entry for deep graph rewriting.
    
    * etc/news.scm: Add entry.
---
 etc/news.scm | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/etc/news.scm b/etc/news.scm
index 1ef238c..2377482 100644
--- a/etc/news.scm
+++ b/etc/news.scm
@@ -13,6 +13,30 @@
 (channel-news
  (version 0)
 
+ (entry (commit "8819551c8d2a12cd4e84e09b51e434d05a012c9d")
+        (title (en "Package transformations now apply to implicit inputs"))
+        (body
+         (en "Package transformation options such as @option{--with-branch},
+@option{--with-input}, and so on now apply to implicit inputs---previously
+only a package's explicit inputs would be affected.  This allows for things
+such as replacing the Python dependency of a package that uses
+@code{python-build-system}:
+
+@example
+guix install --with-input=python=python2 python-itsdangerous
+@end example
+
+Another example is grafting a different version of the GNU C
+Library (@code{glibc} is an implicit input of almost all the packages and is
+``deep down'' in the dependency graph):
+
+@example
+guix build --with-graft=glibc=glibc@@2.31 hello
+@end example
+
+Run @command{info \"(guix) Package Transformation Options\"} for more
+info.")))
+
  (entry (commit "a98712785e0b042a290420fd74e5a4a5da4fc68f")
         (title (en "New @command{guix git authenticate} command")
                (de "Neuer Befehl @command{guix git authenticate}")