function child(_sources: any, num: any) {
      const vdom$ = _sources.HTTP.select('cat').pipe(
        mergeAll(),
        map((res: any) => 'My name is ' + res.text)
      );

      const request$ =
        num === 1
          ? of({
              category: 'cat',
              url: uri + '/hello',
            })
          : never();

      return {
        HTTP: request$,
        DOM: vdom$,
      };
    }

 function main(_sources: {history: Observable<Location>}) {
   assert.strictEqual(typeof _sources.history.pipe, 'function');
   return {
     history: never() as Observable<string>,
   };
 }

 catchError(err => {
     console.log("Error generating new user token: ", err);
     return never();
 }),

 locationChanges(): Observable<Location> {
   return never();
 }

 switchMap(t => t == "" ? never() : timer(0, 3600000)),