Trouble configuring guix

[Cássio Tavares]

Hello there!

Well, I need help...

## Context:

  * I have just a little familiarity with Guile Scheme, because I'm a
    LilyPond user;
  * I finally have a desktop that doesn't need non-libre drivers;
  * Although I'm not in the Tech world, I love GNU's (and the FSF's)
    philosophy;
  * I have been playing with Nix, but find it very cryptic -- not easy
    to understand at all.

  So, Guix seems to be the path I'm on now.

## Situation:

  I have several problems to fix, but the most important right now is
  to get my keyboard to work with sddm, and I need sddm for
  Wayland. So, without sddm, this works:

```
    ...

    (define %this-keyboard  (keyboard-layout "br" "abnt2"))

    ...

    (operating-system
      ...

      (keyboard-layout  %this-keyboard)

      ... )

```

  But `guix system reconfigure /etc/config.scm` fails when this is this:

```
    (use-modules
      (gnu)
      (gnu system nss)
      (gnu services networking)
      (gnu services sddm)
      (gnu services cups)
      (gnu services desktop)
      (gnu services ssh)
      (gnu services xorg))

    ...

    (define %this-keyboard (keyboard-layout  "br" "abnt2"))

    ...

    (operating-system
      ...

      (keyboard-layout  %this-keyboard)

      ...

      (services
        (append
          (list
            (service dhcp-client-service-type)
            (service ntp-service-type)
            (service gpm-service-type)
            (service cups-service-type)
            (service elogind-service-type)
            (service sddm-service-type
              (sddm-configuration
                (display-server "wayland")
                (numlock "on")
                (theme "guix-simplyblack-sddm-theme")
                (xorg-configuration
                  (keyboard-layout %this-keyboard)))))
          %base-services))

      ... )

```

  Then, when I try to run `guix system reconfigure /etc/config.scm`, I
  get this backtrace:

> root@udu ~#
  > Backtrace:
  >           19 (primitive-load "/root/.config/guix/current/bin/guix")
  > In guix/ui.scm:
  >    2229:7 18 (run-guix . _)
  >   2192:10 17 (run-guix-command _ . _)
  > In ice-9/boot-9.scm:
  >   1752:10 16 (with-exception-handler _ _ #:unwind? _ # _)
  > In guix/status.scm:
  >     829:3 15 (_)
  >     809:4 14 (call-with-status-report _ _)
  > In guix/scripts/system.scm:
  >    1256:4 13 (_)
  > In ice-9/boot-9.scm:
  >   1752:10 12 (with-exception-handler _ _ #:unwind? _ # _)
  > In guix/store.scm:
  >    658:37 11 (thunk)
  >    1320:8 10 (call-with-build-handler #<procedure 7faf357d0060 at g…> …)
  >   2129:25  9 (run-with-store #<store-connection 256.99 7faf38008190> …)
  > In guix/scripts/system.scm:
  >     827:2  8 (_ _)
  >     703:8  7 (_ #<store-connection 256.99 7faf38008190>)
  > In gnu/system.scm:
  >   1227:19  6 (operating-system-derivation _)
  >    748:11  5 (operating-system-services #<<operating-system> kernel:…>)
  >    782:20  4 (services _)
  > In /etc/config.scm:
  >    185:14  3 (services #<<operating-system> kernel: #<package linux-…>)
  >    185:14  2 (services #<<keyboard-layout> name: "br" variant: "abnt…>)
  > In ice-9/boot-9.scm:
  >   1685:16  1 (raise-exception _ #:continuable? _)
  >   1685:16  0 (raise-exception _ #:continuable? _)
  >
  > ice-9/boot-9.scm:1685:16: In procedure raise-exception:
  > Wrong type to apply: #<<keyboard-layout> name: "br" variant:
"abnt2" model: #f options: ()>

## Conclusion:

  Two things tell me that the problem is really in the keyboard
  configuration within the configuration of the sddm service:

  * When I remove the `xorg-configuration` from the `sddm-configuration`,
    the reconfiguration returns no error, and the sddm service works
    normally.
  * And in this setup, the keyboard works on the console, just not on the
    desktop environment.

Best regards,
And thank you.

Cassio