Cannot export self module as default

[Fenzland]

TypeScript Version: 3.8.3

Search Terms:
module import export circular

Background
I use to write module like this:

// module.js
export { foo, bar, baz, };
export * as default from './module.js'; // path of current file itself.

Then we can import the module with both to ways:

import { foo, } from './module.js';
import Module from './module.js';

Module.foo === foo; // true

That's work fine with JavaScript but not TypeScript.

Code

// module.ts
export * as default './module.ts';

Expected behavior: works like JavaScript.

Actual behavior:

error TS1359: Identifier expected. 'default' is a reserved word that cannot be used here.
export * as default from './module.ts';
            ~~~~~~~

So I modify my code to:

// module.ts
import * as Module './module.ts';
export default Module;

This works fine with JavaScript too, but not TypeScript again.

Expected behavior: works like JavaScript.

Actual behavior:

error TS2303: Circular definition of import alias 'Module'.
import * as Module from './test.ts';
       ~~~~~~~~~~~

I modify my code again to:

// module.ts
import * as Module './module.ts';
export default (Module);

It finally works, both JavaScript and TypeScript.

[rbuckton]

This was fixed by #39803 and shipped in TS 4.1.