cosmic module

modules/validations.nix

@@ -0,0 +1,22 @@
+{ lib, config, ... }:
+{
+  # config.assertions = [
+  #   {
+  #     assertion =
+  #       lib.length (
+  #         lib.filter (x: x) [
+  #           config.my_modules.de_cosmic.enable
+  #           config.my_modules.de_gnome_xorg.enable
+  #           config.my_modules.de_gnome_wayland.enable
+  #         ]
+  #       ) <= 1;
+  #     message = ''
+  #       Configuration Error: Multiple desktop environments are enabled.
+  #       Please enable only one of the following:
+  #         - my_modules.de_cosmic.enable
+  #         - my_modules.de_gnome_xorg.enable
+  #         - my_modules.de_gnome_wayland.enable
+  #     '';
+  #   }
+  # ];
+}