athemyst.nix

{ lib, config, ... }:

with lib;

let
  cfg = config.shabka.amethyst;

  keyboardShortcutOptions = {
    options = with types; {
      mod = mkOption {
        type = enum ["mod1" "mod2"];
      };
      key = mkOption {
        type = enum ["a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k" "l" "m" "n" "o" "p" "q" "r" "s" "t" "u" "v" "w" "x" "y" "z"];
      };
    };
  };

in {
  options.shabka.amethyst = {
    enable = mkEnableOption "Automatic tiling window manager for macOS à la xmonad";

    cycle-layout = {
      type = types.submodule keyboardShortcutOptions;
      default = {
        mod = "mod1";
        key = "space";
      };
    };
  };

  config = mkIf cfg.enable {
    home.file.".amethyst".text = builtins.toJSON (builtins.removeAttrs cfg ["enable" "_module"]);
  };
}

shell.sh-session

 λ nix repl
Welcome to Nix version 2.3.2. Type :? for help.

nix-repl> lib = (import <nixpkgs> {}).lib

nix-repl> config = lib.evalModules { modules = [ ./modules/home/software/amethyst.nix ]; }

nix-repl> config
warning: Nix search path entry '/nix/var/nix/profiles/per-user/root/channels' does not exist, ignoring
{ config = { ... }; options = { ... }; }

nix-repl> config.config
{ _module = { ... }; shabka = { ... }; }

nix-repl> config.config.shabka
{ amethyst = { ... }; }

nix-repl> config.config.shabka.amethyst
error: value is a string while a set was expected, at /nix/store/9cy9n30pzg98xv1k76dwgpfliknl4laq-szrnwkyylgsas8p82xysg0dqa4a22aka-nixpkgs-release-unstable-90441b4b47fc7280de6a5bd1a228017caaa0f97f/lib/modules.nix:262:25