krebs.retiolum: define type of hosts

1systems/tv/cd.nix

@@ -89,7 +89,6 @@ in
       imports = [ ../../3modules/krebs/retiolum.nix ];
       krebs.retiolum = {
         enable = true;
-        hosts = ../../Zhosts;
         connectTo = [
           "fastpoke"
           "pigstarter"

1systems/tv/mkdir.nix

@@ -32,7 +32,6 @@ with lib;
       imports = [ ../../3modules/krebs/retiolum.nix ];
       krebs.retiolum = {
         enable = true;
-        hosts = ../../Zhosts;
         connectTo = [
           "cd"
           "fastpoke"

1systems/tv/nomic.nix

@@ -40,7 +40,6 @@ with lib;
       imports = [ ../../3modules/krebs/retiolum.nix ];
       krebs.retiolum = {
         enable = true;
-        hosts = ../../Zhosts;
         connectTo = [
           "gum"
           "pigstarter"

1systems/tv/rmdir.nix

@@ -32,7 +32,6 @@ with lib;
       imports = [ ../../3modules/krebs/retiolum.nix ];
       krebs.retiolum = {
         enable = true;
-        hosts = ../../Zhosts;
         connectTo = [
           "cd"
           "mkdir"

1systems/tv/wu.nix

@@ -148,7 +148,6 @@ in
       imports = [ ../../3modules/krebs/retiolum.nix ];
       krebs.retiolum = {
         enable = true;
-        hosts = ../../Zhosts;
         connectTo = [
           "gum"
           "pigstarter"

3modules/krebs/retiolum.nix

@@ -57,9 +57,9 @@ let
     };
 
     hosts = mkOption {
-      default = null;
+      type = with types; either package path;
+      default = ../../Zhosts;
       description = ''
-        Hosts package or path to use.
         If a path is given, then it will be used to generate an ad-hoc package.
       '';
     };
@@ -127,24 +127,20 @@ let
   };
 
   tinc = cfg.tincPackage;
-  hostsType = builtins.typeOf cfg.hosts;
-  hosts =
-    if hostsType == "package" then
-      # use package as is
-      cfg.hosts
-    else if hostsType == "path" then
-      # use path to generate a package
-      pkgs.stdenv.mkDerivation {
+
+  hosts = getAttr (typeOf cfg.hosts) {
+    package = cfg.hosts;
+    path = pkgs.stdenv.mkDerivation {
       name = "custom-retiolum-hosts";
       src = cfg.hosts;
       installPhase = ''
         mkdir $out
-          find . -name .git -prune -o -type f -print0 | xargs -0 cp --target-directory $out
+        find . -name .git -prune -o -type f -print0 \
+          | xargs -0 cp --target-directory $out
       '';
-      }
-    else
-      abort "The option `services.retiolum.hosts' must be set to a package or a path"
-    ;
+    };
+  };
+
   iproute = cfg.iproutePackage;
 
   retiolumExtraHosts = import (pkgs.runCommand "retiolum-etc-hosts"
@@ -222,5 +218,5 @@ let
 
     chmod +x $out/tinc-up
   '';
-in
-out
+
+in out