u

Bar.js

+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
 var Bar = /** @class */ (function () {
     function Bar() {
         console.log('im bar');
     }
     return Bar;
 }());
-export default Bar;
+exports.default = Bar;

Foo.js

+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
 var Foo = /** @class */ (function () {
     function Foo() {
         console.log('im foo');
     }
     return Foo;
 }());
-export default Foo;
+exports.default = Foo;

index.js

-export default function (num) {
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+function default_1(num) {
     return Math.round(num);
 }
+exports.default = default_1;

tsconfig.json

 {
   "compilerOptions": {
     "target": "es5",                          /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017','ES2018' or 'ESNEXT'. */
-    "module": "es6"                     /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */
+    "module": "commonjs"                   /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */
     }
 }
\ No newline at end of file