fix(factory): func without export

lib/factory.js

@@ -9,7 +9,7 @@
  * @param {new T } cls
  * @returns {T[] | []}
  */
-function factory(values, cls) {
+export function factory(values, cls) {
   if (values.length) {
     return values.map((val) => new cls(val));
   }