content_copyopen_in_new
import { of } from 'rxjs';
import { mergeMap, groupBy, reduce } from 'rxjs/operators';
of(
{id: 1, name: 'JavaScript'},
{id: 2, name: 'Parcel'},
{id: 2, name: 'webpack'},
{id: 1, name: 'TypeScript'},
{id: 3, name: 'TSLint'}
).pipe(
groupBy(p => p.id),
mergeMap((group$) => group$.pipe(reduce((acc, cur) => [...acc, cur], [])))
)
.subscribe(p => console.log(p));
// displays:
// [ { id: 1, name: 'JavaScript'},
// { id: 1, name: 'TypeScript'} ]
//
// [ { id: 2, name: 'Parcel'},
// { id: 2, name: 'webpack'} ]
//
// [ { id: 3, name: 'TSLint'} ]