import { interval, throwError, of } from 'rxjs';
import { mergeMap, ignoreElements } from 'rxjs/operators';
const source = interval(100);
//ignore everything but error
const error = source.pipe(
return throwError(`ERROR AT ${val}`);
//output: "ERROR: ERROR AT 4"
const subscribe = error.subscribe(
val => console.log(`NEXT: ${val}`),
val => console.log(`ERROR: ${val}`),
() => console.log('SECOND COMPLETE!')