title: Property does not exist on type 'never' in Ngrx effect
body: <p>I'm using Angular 8 and NGRX 8. I have an action:</p>
  
  <pre><code>export const loadEnvironment = createAction(
    LicencingActionTypes.LoadEnvironment,
    props&lt;{environment: Environment}&gt;()
  );
  </code></pre>
  
  <p>and corresponding effect:</p>
  
  <pre><code> loadEnvironment = createEffect(() =&gt; this.actions$.pipe(
      ofType(LicencingActionTypes.LoadEnvironment),
      exhaustMap((action) =&gt;
        this.authService.
        getToken(LicencingEffects.getAuthDetailsForEnvironment(action.environment))
          .pipe(
            switchMap((token) =&gt; [
              AuthActions.onLogin({token: token}),
              LicencingActions.onLoadEnvironment({environment: action.environment})
            ]),
            catchError(error =&gt; of(AuthActions.onLoginError({error: error})))
          )
      )
    ));
  </code></pre>
  
  <p>I've been reading the documentation on NGRX 8 (<a href="https://ngrx.io/guide/effects#incorporating-state" rel="nofollow noreferrer">https://ngrx.io/guide/effects#incorporating-state</a>).</p>
  
  <p>Their example shows that you can just use the action property without casting the type of the action:</p>
  
  <pre><code>...
  exhaustMap(action =&gt;
          this.authService.login(action.credentials)
  ...
  </code></pre>
  
  <p>Webpack won't compile, and I get the following error:</p>
  
  <pre><code>ERROR in src/app/licencing/effects/licencing.effects.ts(20,69): error TS2339: Property 'environment' does not exist on type 'never'.
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/LMrxS.png" rel="nofollow noreferrer">Screenshot of code with errors highlighted</a></p>
  
  <p>Where am I going wrong?</p>