diff --git a/examples/enum.js b/examples/enum.js
index d58da5d..2bb94bd 100644
--- a/examples/enum.js
+++ b/examples/enum.js
@@ -4,7 +4,7 @@ import { unit } from "../lib/primitives/unit.js";
 import { makeConstructors, makeMatchFn } from "../lib/structures/enum.js";
 import { enumType } from "../lib/structures/enum.types.js";
 import { newProduct } from "../lib/structures/product.js";
-import { lsType } from "../lib/structures/type_constructors.js";
+import { lsType } from "../lib/structures/type_constructors.types.js";
 import { prettyT } from "../lib/util/pretty.js";
 
 Error.stackTraceLimit = Infinity;
@@ -15,10 +15,10 @@ const variants = [
   newProduct("not_found")(_ => Unit),
 ];
 
-const compatibleNestedSumType = enumType(variants);
+const structuralType = enumType(variants);
 
 console.log("observe the type that was generated:");
-console.log(" ", prettyT(compatibleNestedSumType));
+console.log(" ", prettyT(structuralType));
 
 const [newPrice, newPrices, newNotFound] = makeConstructors(variants);
 
@@ -41,7 +41,7 @@ console.log(" ", myEnumToString(price));
 console.log(" ", myEnumToString(prices));
 console.log(" ", myEnumToString(notFound));
 
-const compareMyEnum = makeCompareFn(compatibleNestedSumType);
+const compareMyEnum = makeCompareFn(structuralType);
 
 console.log("observe the generated compare function in action:");
 console.log("  should be smaller ->", compareMyEnum(price)(prices));
diff --git a/lib/structures/enum.types.js b/lib/structures/enum.types.js
index bb17875..3c3fd6c 100644
--- a/lib/structures/enum.types.js
+++ b/lib/structures/enum.types.js
@@ -1,10 +1,10 @@
 import { makeCompareFn } from "../compare/dynamic.js";
 import { makeGeneric } from "../generics/generics.js";
 import { newDynamic } from "../primitives/dynamic.js";
-import { Bottom, Type } from "../primitives/primitive_types.js";
+import { Bottom } from "../primitives/primitive_types.js";
 import { makeConstructors, makeMatchFn } from "./enum.js";
 import { getRight } from "./product.js";
-import { fnType, sumType } from "./type_constructors.js";
+import { fnType, sumType } from "./type_constructors.types.js";
 
 // 'variants' is an array of (name: string, type: Type) pairs.
 // e.g., the list of variants:
@@ -77,4 +77,5 @@ export const makeModuleEnum = type => variants => {
     // compare-function:
     newDynamic(makeCompareFn(enumType(variants)))
   ];
+  return module;
 }
\ No newline at end of file