TEMP: add Null type

nt/primitives/util/bootstrap.nix

@@ -5,6 +5,7 @@ let
     import ./util.nix input
     // import ./parse.nix input
     // import ./trapdoor.nix input
+    // import ./null.nix input
     // import ./wrap.nix input
     // import ./enforce.nix input
     // import ./sig.nix input

nt/primitives/util/default.nix

@@ -3,6 +3,7 @@ mix.newMixture inputs (mixture: {
   includes.public = [
     ./enforce.nix
     ./nt.nix
+    ./null.nix
     ./parse.nix
     ./sig.nix
     ./trapdoor.nix

nt/primitives/util/null.nix

@@ -0,0 +1,24 @@
+# XXX: TODO: replace Null with the naive Maybe type
+{this, ...}: let
+  inherit
+    (this)
+    ntTrapdoorKey
+    mkTrapdoorSet
+    ;
+in {
+  # NOTE: This is not good for writing type safe code
+  # NOTE: it is however efficient for bootstrapping the primitives
+  Null =
+    # WARNING: Null skips implementing a Type altogether
+    # WARNING: Null is an orphaned Type instance
+    mkTrapdoorSet ntTrapdoorKey {
+      default = {};
+      unlock = {
+        instance = true;
+        sig = "nt::Null";
+        derive = [];
+        ops = {};
+        req = {};
+      };
+    };
+}

nt/primitives/util/parse.nix

@@ -1,3 +1,4 @@
+# XXX: TODO: use the custom Null type instance instead of the Wrap type
 {this, ...}: let
   inherit
     (builtins)