Dropping repeats in RxJS
RxJS interview exercise on Filtering, difficulty 1 of 3. Solve it in the editor beside a worked example, or cold in Interview mode with the example hidden; the tests run the moment you do.
Write dedupe(source$), dropping a value that equals the previous one, and dedupeById(source$), dropping an object whose `id` equals the previous object's id. Earlier values further back do not count as repeats.
Each exercise pairs a worked example with a twin problem to solve in a real editor; the tests run the moment you do. Interview mode hides the example: solve it from memory, without the hint or the solution, and it counts as solved cold. Progress is saved in your browser, and in your account if you sign in.