Angular 5 ngrx Effect no exported member 'ofType'

Looking at @ngrx/effects API, there's no sign that this library has implemented a lettable version of ofType, so your second implementation won't work (at least not with ofType inside the pipe).

Your first implementation is just missing an import for mergeMap

import 'rxjs/add/observable/mergeMap';

and probably map and catch as well

import 'rxjs/add/observable/map';import 'rxjs/add/observable/catch';

If you want to use ofType with pipe, this will probably work

@Effect()getWifiData: Observable<Action> =   this.actions$.ofType(WifiTypes.getWifiNetworks)    .pipe(      mergeMap((action: GetWifiNetworks) =>      ...

since ofType() returns an Observable which has .pipe already added to it's prototype.

Footnote

After looking through the source code on github (as at 22 Jan 2018), I found an export for lettable ofType here platform/modules/effects/src/index.ts.

But upon installing with @ngrx/effects@latest (which gives me ver 4.1.1) I can't see this export reference under the installed node_modules folder.

In my component, I can't use import { ofType } from '@ngrx/effects'; either.

It looks like the docs are reflecting a nightly release.

https://github.com/ngrx/platform/issues/727

Nightly release is available here: https://github.com/ngrx/effects-builds