The async pipe in Angular

Angular interview exercise on RxJS interop, difficulty 1 of 3. Solve it in the editor beside a worked example; the tests run the moment you do.

ChatComponent has a `messages observable built from the `incoming` Subject with scan, accumulating every message into…" /> observable built from the `incoming` Subject with scan, accumulating every message into…" /> observable built from the `incoming` Subject with scan, accumulating every message into…" /> observable built from the `incoming` Subject with scan, accumulating every message into…" /> observable built from the `incoming` Subject with scan, accumulating every message into…" /> observable built from the `incoming` Subject with scan, accumulating every message into…" /> observable built from the `incoming` Subject with scan, accumulating every message into…" /> observable built from the `incoming` Subject with scan, accumulating every message into an array (starting from []). Render them as <li> with the async pipe, and the count in <p class="count"> as "N messages".

Each exercise pairs a worked example with a twin problem to solve in a real editor; the tests run the moment you do. Progress is saved in your browser, and in your account if you sign in.

More RxJS interop in Angular

• An observable as a signal
• Debounced search with switchMap
• Subscriptions that end with the component
• A store driven by a Subject

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