Use @types definitions in project .d.ts definition file

Question

I'm trying to write a .d.ts file for my project to define some global interfaces. However I have a problem using non-global library types inside that definition file. Especially RxJs which I'm trying to reference does not work for me.

The thing I thought would work the best was using a triple-slash reference tag to import the types for RxJs, however this didn't work.

/// <reference types="rxjs" />

interface IUserService {
    user$: rxjs.Observable<IUser>;
}

Answer 1

I found the solution to what I wanted to do:

import RxJs from 'rxjs';

declare global {

    interface IUserService {
        user$: RxJs.Observable<IUser>;
    }

}

Using declare global { } I was able to get back into the global namespace. Typescript is really lacking documentation on this useful directive which is only documented slightly at the end of this page: https://www.typescriptlang.org/docs/handbook/declaration-merging.html#global-augmentation.