Musics,

musics--- via Bug reports for GNU Guix 写道：
> I changed the config.scm file, after running "sudo guix system 
> reconfigure /etc/config.scm" it displayed:
> /etc/config.scm:31:6: error: network-manager-type: unbound 
> variable
> hint: Did you forget a ʻuse-modules' form?

You need to import the module that provides 
‘network-manager-type’.  Sometimes Guix suggests the module name 
in the hint, but not here.

You can find out the file name with ‘guix system search 
network-manager’ (eventually you'll ‘just know’, or grep the 
source ;-)

If the file name is gnu/services/networking.scm, the Guile module 
name is (gnu services networking).  This is a rule.

If you're using regular Guile use-modules syntax:

  (use-modules ...
               (gnu services networking)
               ...)

Or the Guix-specific use-service-modules syntax:

  (use-service-modules ...
                       networking
                       ...)

The latter is less verbose over time but both do the exact same 
thing.

Kind regards,

T G-R