package.json

@@ -18,6 +18,16 @@
         "types": "./dist/lib.d.cts",
         "default": "./dist/lib.cjs"
       }
+    },
+    "./util": {
+      "import": {
+        "types": "./dist/util.d.mts",
+        "default": "./dist/util.mjs"
+      },
+      "require": {
+        "types": "./dist/util.d.cts",
+        "default": "./dist/util.cjs"
+      }
     }
   },
   "scripts": {

rollup.config.ts

@@ -5,30 +5,40 @@ import ts from "rollup-plugin-ts"
 import pkg from "./package.json" assert { type: "json" }
 
 
-export default defineConfig({
+export const createBundleConfig = (
-    input: "src/lib.ts",
+    input:  string,
+    name:   keyof typeof pkg.exports,
+) => (
+    defineConfig({
+        input,
 
-    output: [
+        output: [
-        {
+            {
-            file:    pkg.exports["."].import.default,
+                file:    pkg.exports[name].import.default,
-            format:  "esm",
+                format:  "esm",
-        },
+            },
+            {
+                file:    pkg.exports[name].require.default,
+                format:  "cjs",
+            },
+        ],
 
-        {
+        external: id => !/^[./]/.test(id),
-            file:    pkg.exports["."].require.default,
-            format:  "cjs",
-        },
-    ],
 
-    external: id => !/^[./]/.test(id),
+        plugins: [
+            nodeResolve(),
+            ts(),
 
-    plugins: [
+            cleanup({
-        nodeResolve(),
+                comments: "jsdoc",
-        ts(),
+                extensions: ["ts"],
+            }),
+        ],
+    })
+)
 
-        cleanup({
+
-            comments: "jsdoc",
+export default [
-            extensions: ["ts"],
+    createBundleConfig("src/lib.ts", "."),
-        }),
+    createBundleConfig("src/util/lib.ts", "./util"),
-    ],
+]
-})

src/lib.ts

@@ -1,5 +1,6 @@
 export {
     abstract, expression, trait,
+    type Implements,
     type Trait,
     type TraitExpression
 } from "."

src/util/lib.ts

@@ -0,0 +1,6 @@
+export {
+    Extend,
+    ExtendFn,
+    Extendable,
+    ExtendableFn
+} from "."