lib.types.pkgs: init

A nominal type.

1 files changed, 8 insertions, 0 deletions

diff --git a/lib/types.nix b/lib/types.nix
index e0da18a2febb9..373d0ce7876f9 100644
--- a/lib/types.nix
+++ b/lib/types.nix
@@ -476,6 +476,14 @@ rec {
       check = x: isDerivation x && hasAttr "shellPath" x;
     };
 
+    pkgs = addCheck
+      (unique { message = "A Nixpkgs pkgs set can not be merged with another pkgs set."; } attrs // {
+        name = "pkgs";
+        descriptionClass = "noun";
+        description = "Nixpkgs package set";
+      })
+      (x: (x._type or null) == "pkgs");
+
     path = mkOptionType {
       name = "path";
       descriptionClass = "noun";