From 608982d8f27a0f74d73e70cdfcf04841a72cb212 Mon Sep 17 00:00:00 2001
From: Zynh Ludwig <zynh0722@gmail.com>
Date: Fri, 28 Jun 2024 07:48:26 -0700
Subject: [PATCH] more rework

---
 flake.nix       | 49 ++++++++++++++++++++++++++++++-------------------
 lib/default.nix | 16 ++++++++++++++++
 2 files changed, 46 insertions(+), 19 deletions(-)
 create mode 100644 lib/default.nix

diff --git a/flake.nix b/flake.nix
index c4231b6..514aa48 100644
--- a/flake.nix
+++ b/flake.nix
@@ -17,29 +17,40 @@
     };
   };
 
-  outputs = { self, nixpkgs, ... }@inputs:
+  outputs =
+    { self, nixpkgs, ... }@inputs:
     {
       nixosConfigurations =
         let
+          lib = import ./lib { inherit (nixpkgs) lib; };
+
           cleanHostname = config: builtins.removeAttrs config [ "hostname" ];
-          toNixosConfigPart = config: { name = config.hostname; value = nixpkgs.lib.nixosSystem (cleanHostname config); };
+          toPartialNixosConfigSet = config: { name = config.hostname; value = nixpkgs.lib.nixosSystem (cleanHostname config); };
+          toNixosSystemConfig = { hostname, system }: {
+            inherit system hostname;
+            specialArgs = { inherit inputs; };
+            modules = [
+              ./hosts/${hostname}/hardware-configuration.nix
+              ./hosts/${hostname}/configuration.nix
+              inputs.home-manager.nixosModules.default
+            ];
+          };
+          compileSystems = systems: lib.right builtins.listToAttrs (map toPartialNixosConfigSet) (map toNixosSystemConfig) systems;
         in
-        builtins.listToAttrs
-          (map toNixosConfigPart
-            (map
-              ({ hostname, system }: {
-                inherit system hostname;
-                specialArgs = { inherit inputs; };
-                modules = [
-                  ./hosts/${hostname}/hardware-configuration.nix
-                  ./hosts/${hostname}/configuration.nix
-                  inputs.home-manager.nixosModules.default
-                ];
-              })
-              [
-                { hostname = "snowhawk"; system = "x86_64-linux"; }
-                { hostname = "sprite"; system = "aarch64-linux"; }
-                { hostname = "nixos"; system = "x86_64-linux"; }
-              ]));
+        compileSystems
+          [
+            {
+              hostname = "snowhawk";
+              system = "x86_64-linux";
+            }
+            {
+              hostname = "sprite";
+              system = "aarch64-linux";
+            }
+            {
+              hostname = "nixos";
+              system = "x86_64-linux";
+            }
+          ];
     };
 }
diff --git a/lib/default.nix b/lib/default.nix
new file mode 100644
index 0000000..ae27ddc
--- /dev/null
+++ b/lib/default.nix
@@ -0,0 +1,16 @@
+{ lib, ... }:
+with lib;
+rec {
+  # Ternary operator
+  # Exaample:
+  # tern false 1 2 => 2
+  # tern true 1 2 => 1
+  tern = pred: x: y: if pred then x else y;
+
+  # Right-associate and chain following single-operand functions
+  # Example:
+  # right f g h 1 => f(g(h(1)))
+  right = f: g: tern (isFunction g)
+    (right (x: f (g (x))))
+    (f (g));
+}