import writers from stockholm 0bc2409

lib/default.nix

@@ -0,0 +1,24 @@
+let {
+  body = lib;
+
+  lib = nixpkgs.lib // builtins // (with lib; {
+    genAttrs' = names: f: listToAttrs (map f names);
+    getAttrs = names: set:
+      listToAttrs (map (name: nameValuePair name set.${name})
+                       (filter (flip hasAttr set) names));
+    toC = x: let
+      type = typeOf x;
+      reject = throw "cannot convert ${type}";
+    in {
+      list = "{ ${concatStringsSep ", " (map toC x)} }";
+      null = "NULL";
+      set = if isDerivation x then toJSON x else reject;
+      string = toJSON x; # close enough
+    }.${type} or reject;
+    test = re: x: isString x && testString re x;
+    testString = re: x: match re x != null;
+    types = nixpkgs.lib.types // import ./types.nix { lib = body; };
+  });
+
+  nixpkgs.lib = import <nixpkgs/lib>;
+}

lib/types.nix

@@ -0,0 +1,23 @@
+{ lib, ... }:
+with lib;
+rec {
+  # POSIX.1‐2013, 3.2 Absolute Pathname
+  absolute-pathname = mkOptionType {
+    name = "POSIX absolute pathname";
+    check = x: isString x && substring 0 1 x == "/" && pathname.check x;
+    merge = mergeOneOption;
+  };
+
+  file-mode = mkOptionType {
+    name = "file mode";
+    check = test "[0-7]{4}";
+    merge = mergeOneOption;
+  };
+
+  # POSIX.1‐2013, 3.278 Portable Filename Character Set
+  filename = mkOptionType {
+    name = "POSIX filename";
+    check = test "([0-9A-Za-z._])[0-9A-Za-z._-]*";
+    merge = mergeOneOption;
+  };
+}