Modular, context-aware and aspect-oriented dendritic Nix configurations.
Discussions: https://oeiuwq.zulipchat.com/join/nqp26cd4kngon6mo3ncgnuap/
den.oeiuwq.com
configurations
den
dendritic
nix
aspect
oriented
feat: default.nix exposes clean den API without NixOS domain (#230)
Closes #224
authored by
GitHub
57aef304
dd995a7e
+1
-1
.github/workflows/test.yml
+1
-1
.github/workflows/test.yml
+10
-1
default.nix
+10
-1
default.nix
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-18
docs/src/content/docs/explanation/library-vs-framework.mdx
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-18
docs/src/content/docs/explanation/library-vs-framework.mdx
···
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## Den as a Library
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Den's core (`nix/lib.nix`) is domain-agnostic. It provides:
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| Function | Purpose |
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|---|---|
···
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## Using Den for Non-OS Domains
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Nothing about `den.lib` assumes NixOS, Darwin, or Home Manager. You can build
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context pipelines for any Nix module system:
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```nix
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-
{ my-aspects, den, ... }: {
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-
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# create a private isolated aspect namespace independent of den.aspects
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imports = [ (den.namespace "my-aspects" false) ];
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# Define aspects for a custom domain
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my-aspects = {
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web-server = den.lib.parametric {
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terranix.resource.aws_instance.web = { ami = "..."; };
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includes = [
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# configures using the terranix Nix class
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({ env, ... }: { terranix.resource.aws_instance.web.tags.Env = env; })
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];
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};
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};
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# Resolve for your custom class
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aspect = my-aspects.web-server { env = "production"; };
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module = aspect.resolve { class = "terranix"; };
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}
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```
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## Den as a Framework
···
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## Den as a Library
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Den's core (`/default.nix`) is domain-agnostic. It provides:
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| Function | Purpose |
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|---|---|
···
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## Using Den for Non-OS Domains
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<Aside title="Source" icon="github">
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[default.nix](https://github.com/vic/den/tree/main/default.nix) - [CI test: den-as-lib.nix](https://github.com/vic/den/tree/main/templates/ci/modules/features/den-as-lib.nix)
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</Aside>
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Nothing about `den.lib` assumes NixOS, Darwin, or Home Manager. You can build
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context pipelines for any Nix module system:
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```nix
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# see den-as-lib.nix CI test for working example
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# Define aspects for a custom domain
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den.aspects = {
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web-server = den.lib.parametric {
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terranix.resource.aws_instance.web = { ami = "..."; };
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includes = [
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# configures using the terranix Nix class
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({ env, ... }: { terranix.resource.aws_instance.web.tags.Env = env; })
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];
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};
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};
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# Resolve for your custom class
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aspect = den.aspects.web-server { env = "production"; };
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module = aspect.resolve { class = "terranix"; };
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```
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## Den as a Framework
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modules/aspects.nix
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modules/aspects.nix
···
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denfulType = lib.types.attrsOf aspectsType;
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in
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{
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config._module.args.den = config.den;
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options.den.aspects = lib.mkOption {
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description = "Den Aspects";
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default = { }; # generated from den.{hosts, homes, users}
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type = aspectsType;
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};
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options.den.ful = lib.mkOption {
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default = { }; # namespaces (local or merged from inputs)
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type = denfulType;
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modules/context/types.nix
nix/nixModule/ctx.nix
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-1
modules/context/types.nix
nix/nixModule/ctx.nix
+3
-6
modules/lib.nix
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-6
modules/lib.nix
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nix/default.nix
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nix/default.nix
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nix/lib.nix
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nix/lib.nix
···
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home-env = import ./home-env.nix { inherit lib den inputs; };
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nixModule = import ./nixModule {
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inherit
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lib
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inputs
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config
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den-lib
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;
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};
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den-lib = {
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inherit
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parametric
···
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ctxApply
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nh
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home-env
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nixModule
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;
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};
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in
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nix/nixModule/aspects.nix
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nix/nixModule/aspects.nix
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nix/nixModule/default.nix
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nix/nixModule/default.nix
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nix/nixModule/lib.nix
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nix/nixModule/lib.nix
+126
templates/ci/modules/features/den-as-lib.nix
+126
templates/ci/modules/features/den-as-lib.nix
···
···
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{
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inputs,
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lib,
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config,
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...
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}:
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let
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denPath = inputs.den.outPath;
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denModule = (import denPath).nixModule inputs;
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in
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{
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flake.tests.den-as-lib = {
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+
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test-expose-lib-functions =
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let
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den-lib = import denPath { inherit lib config inputs; };
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expr = den-lib.canTake.exactly { x = 1; } ({ x, y }: { });
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expected = false;
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in
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{
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inherit expr expected;
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};
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+
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test-module-usable-in-any-module-system =
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let
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ev = lib.evalModules { modules = [ denModule ]; };
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expr = ev.config.den ? lib.parametric;
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expected = true;
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in
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{
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inherit expr expected;
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};
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+
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test-module-has-empty-ctx =
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let
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ev = lib.evalModules { modules = [ denModule ]; };
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expr = lib.attrNames ev.config.den.ctx;
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expected = [ ];
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in
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{
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inherit expr expected;
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};
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+
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test-module-has-empty-aspects =
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let
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ev = lib.evalModules { modules = [ denModule ]; };
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expr = lib.attrNames ev.config.den.aspects;
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expected = [ ];
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in
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{
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inherit expr expected;
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};
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+
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test-module-has-no-nixos-domain =
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let
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names = [
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"hosts"
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"homes"
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"base"
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"default"
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];
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ev = lib.evalModules { modules = [ denModule ]; };
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expr = builtins.all (name: !ev.config.den ? ${name}) names;
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expected = true;
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in
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{
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inherit expr expected;
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};
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test-module-can-resolve-custom-domain =
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let
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ev = lib.evalModules {
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modules = [
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denModule
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module
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];
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};
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module =
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{ den, lib, ... }:
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{
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den.ctx.foo.provides.foo =
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{ name }:
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{
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my.names = [ "foo ${name}" ];
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};
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den.ctx.foo.into.bar = { name }: lib.singleton { shout = lib.toUpper name; };
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den.ctx.foo.provides.bar =
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{ shout }:
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{
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my.names = [ "foo shouted ${shout}" ];
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};
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den.ctx.bar.provides.bar =
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{ shout }:
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{
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my.names = [ "bar ${shout}" ];
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};
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den.aspects.foobar.includes = [
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(den.ctx.foo { name = "good"; })
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];
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};
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myMod = ev.config.den.aspects.foobar.resolve { class = "my"; };
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nameMod.options.names = lib.mkOption { type = lib.types.listOf lib.types.str; };
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ev2 = lib.evalModules {
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modules = [
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nameMod
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myMod
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];
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};
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expr = ev2.config.names;
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expected = [
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"foo shouted GOOD"
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"bar GOOD"
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"foo good"
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];
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in
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{
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inherit expr expected;
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};
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+
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};
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}