// RxJS v6+
import { of } from 'rxjs';
import { distinct } from 'rxjs/operators';
​
of(1, 2, 3, 4, 5, 1, 2, 3, 4, 5)
  .pipe(distinct())
  // OUTPUT: 1,2,3,4,5
  .subscribe(console.log);

// RxJS v6+
import { from } from 'rxjs';
import { distinct } from 'rxjs/operators';
​
const obj1 = { id: 3, name: 'name 1' };
const obj2 = { id: 4, name: 'name 2' };
const obj3 = { id: 3, name: 'name 3' };
const vals = [obj1, obj2, obj3];
​
from(vals)
  .pipe(distinct(e => e.id))
  .subscribe(console.log);
​
/*
OUTPUT:
{id: 3, name: "name 1"}
{id: 4, name: "name 2"}
 */