import {catchError} from "rxjs/operators";
        import {_throw} from "rxjs/observable/throw";
        import {Observable} from "rxjs/Observable";
        import {of} from "rxjs/observable/of";

        const errorObservalbe: Observable<any> = _throw(new Error('some error message'));

        errorObservalbe.pipe(
            catchError((error: Error) => of(error.message))
        ).subscribe(
            (message: string) => {
                console.log(message);
            },
            () => console.log('error wont be called'),
            () => console.log('complete will be called')
        )