Real-life: distinctUntilKeyChanged() route id

Route params arrive as objects. Let through only changes to the id field.

1. Solve the task in the editor — no long theory.
2. Run the check and compare your output with the expected result.
3. Stuck? Open the solution and carry the approach into your own code.

const { from, distinctUntilKeyChanged, map } = Rx;

const params = [{ id: 1 }, { id: 1 }, { id: 2 }, { id: 1 }];

const result$ = from(params).pipe(
  distinctUntilKeyChanged('id'),
  map(param => param.id)
);

result$.subscribe(value => console.log(value));