recursive types (and operations on them, like pretty-printing, comparison and unification) seem to be working.

big part of the code base still needs to be 'ported' to the updated type constructors.

versioning/value.js

@@ -1,11 +1,7 @@
+import { fnType } from "../structures/types.js";
 import { deepEqual } from "../util/util.js";
 import { inspect } from "node:util";
 
-// A Value is either:
-//   - a literal, without any dependencies.
-//   - read from a slot. the Value then has a read-dependency on that slot.
-//   - a transformation of another Value, by a function. the function is also a Value.
-
 // a -> Value<a>
 export const newLiteral = val => ({
   kind: "literal",
@@ -44,7 +40,7 @@ export const transform = input => fn => {
   }
 };
 
-// Value<a> -> Set<Slot<Any>>
+// Value<a> -> Set<Slot<Top>>
 export const getReadDependencies = value => {
   if (value.kind === "literal") {
     return new Set();