Typescript: Unable to re-export a type with Webpack 4

I’m submitting a bug report Webpack Version: 4.4.1 Babel Core Version: 7.0.0-beta.44 Babel Loader Version: 8.0.0-beta.0 Please tell us about your environment:

I am using Bable beta with the typescript preset.

In one file, I define and export a type:

// a.ts
export type MyType = "a" | "b";

In another file, I re-export this type:

// b.ts
export { MyType } from "./a.ts";

Current behavior:

The export line is not present when a.ts is compiled using Babel. The re-export line in b.ts is compiled to:

export { MyType } from "./b";

Webpack fails with this error:

    ERROR in ./app/client/utils.ts
    79:0-51 "export 'myType' was not found in './a'
     @ ./b.ts

Expected/desired behavior:

It worked fine with Webpack 3, I am not sure why. babel should not output anything for the re-export but it does. I am not sure why Webpack 3 was not complaining about the issue, but now Webpack 4 does.

I am not sure if this should be filled in this repo, or with Webpack or Babel core. I can provide a repro if this is needed and the correct place for this issue.

[andy-ms]

You can still do are-export if it’s clear that you’re exporting a type:

import { T as a_T } from "./a";
export type T = a_T;

You can also do export * from "./a";.

[Akiyamka]

@niksumeiko, that cool, but not supported by babel-loader; export type { IGeocoder } from './types'; crush build with Unexpected token error