Set up template

1 files changed, 57 insertions, 0 deletions

diff --git a/utils/default.nix b/utils/default.nix
new file mode 100644
index 00000000..d00357af
--- /dev/null
+++ b/utils/default.nix
@@ -0,0 +1,57 @@
+{ lib }:
+rec {
+  inherit (builtins) readDir;
+  inherit (lib) filterAttrs hasSuffix removeSuffix mapAttrs' nameValuePair isFunction functionArgs setFunctionArgs id;
+  mapFilterAttrs = seive: f: attrs: filterAttrs seive (mapAttrs' f attrs);
+  recImport = { dir, _import ? name: _base: import "${toString dir}/${name}" }:
+    mapFilterAttrs
+      (_: v: v != null)
+      (n: v:
+        if n != "default.nix" && hasSuffix ".nix" n && v == "regular"
+        then
+          let name = removeSuffix ".nix" n; in nameValuePair (name) (_import n name)
+        else
+          if v == "directory"
+          then
+            nameValuePair n (_import n n)
+          else
+            nameValuePair ("") (null))
+      (readDir dir);
+
+  types.attrNameSet = attr:
+    let
+      elemType = lib.types.enum (builtins.attrNames attr);
+    in lib.types.mkOptionType rec {
+      name = "attrNameSet";
+      description = "set of names taken from an attribute set";
+      check = lib.isList;
+      emptyValue = { value = {}; };
+      getSubOptions = prefix: elemType.getSubOptions (prefix ++ ["*"]);
+      getSubModules = elemType.getSubModules;
+      substSubModules = m: lib.types.listOf (elemType.substSubModules m);
+      functor = (lib.types.defaultFunctor name) // { wrapped = elemType; };
+      merge = loc: defs: map (x: x.value) (lib.lists.filter (x: x ? value) (lib.lists.unique (lib.lists.concatLists (lib.lists.imap1 (n: def:
+        lib.lists.imap1 (m: def':
+          (lib.modules.mergeDefinitions
+            (loc ++ ["[definition ${toString n}-entry ${toString m}]"])
+            elemType
+            [{ inherit (def) file; value = def'; }]
+          ).optionalValue
+        ) def.value
+      ) defs))));
+    };
+
+  overrideModuleArgs =
+    let
+      overrideModuleArgs = module: appOverride: if isFunction module then overrideModuleArgs' module appOverride else module;
+      overrideModuleArgs' = module: appOverride: setFunctionArgs (inputs: overrideModuleArgs (module (appOverride inputs)) id) (functionArgs module);
+    in overrideModuleArgs;
+  
+  overrideModuleOutput =
+    let
+      overrideModuleOutput = module: appOverride: if isFunction module then overrideModuleOutput' module appOverride else appOverride module;
+      overrideModuleOutput' = module: appOverride: setFunctionArgs (inputs: overrideModuleOutput (module inputs) appOverride) (functionArgs module);
+    in overrideModuleOutput;
+
+  overrideModule = module: appInput: appOutput: overrideModuleOutput (overrideModuleArgs module appInput) appOutput;
+}