NixOS modules: Difference between revisions

← Older edit Newer edit →

VisualWikitext

@@ Line 174: / Line 174: @@
 Declarations specify a module's external interfaces.
-<syntaxhighlight lang=nix>
+<syntaxhighlight lang="nix">
-optionName = mkOption {
+options = {
-  # ...
+  optionName = mkOption {
+    # ...
+  };
 }
 </syntaxhighlight>
@@ Line 207: / Line 209: @@
 </dl>
+==== Examples ====
+[[File:NixOS Search - Options.png|alt=A search query `programs.bat.` on the official NixOS Search - Options.|thumb|268x268px|For more examples you can browse [https://github.com/NixOS/nixpkgs NixOS/nixpkgs]: Search a similar option on [https://search.nixos.org/options NixOS Search - Options] and click on the link beside "Declared in".]]
+Some useful option examples.<syntaxhighlight lang="nixos">
+{ lib, pkgs, ... }: {
+  options.examples = {
+    enable = lib.options.mkEnableOption "showcasing of options";
+    # type = lib.types.bool;
+    package = lib.options.mkPackageOption pkgs "bash" { };
+    # type = lib.types.package;
+    groceries = lib.options.mkOption {
+      type = lib.types.listOf lib.types.strMatching "^[a-z]*$";
+      default = [];
+      description = "Showcase `listOf` and `strMatching`".
+      example = [
+        "bananas"
+        "cherrys"
+        "Throws an error at evaluation beause of regex not matching."
+      ];
+    };
+    settings = lib.options.mkOption {
+      type = lib.types.json;
+      default = {};
+      description = ''
+        Showcase the possible option for settings of a configuration file.
+        Always document, where you can find possible options e.g.:
+          Refer <https://example.com/> for possible options.
+      '';
+      example = {
+        global = {
+          log_format = "-";
+          log_filter = "^$";
+        };
+      };
+    };
+    units = lib.options.mkOption {
+      type = lib.types.attrsOf (lib.types.submodule (
+        { name, ... }:
+        {
+          options = {
+            name = lib.options.mkOption {
+              type = lib.types.str;
+              default = name;
+              defaultText = "<name>";
+              description = "Name of the unit";
+            };
+            unit = lib.options.mkOption {
+              type = lib.types.str;
+              defaultText = ''
+                Default will be set in the `config` block
+                of the `submodule` (see down below)
+              '';
+              description = "A unit of measurement";
+            };
+          };
+          config = {
+            unit = lib.mkDefault "kg";
+          };
+        }
+      ));
+      default = {};
+      description = "Showcase the combination `attrsOf` and `submodule`";
+      example = {
+        "unit1" = { unit = "m" };
+        "unit2".unit = "cm";
+      };
+    };
+  };
+}
+</syntaxhighlight>
 == Rationale ==