BUG: RxJs chaining operators

> Author: Thomas Laforge Let's dive inside the wonderful word of RxJs. This challenge is inspired by a real-life example. ### Presentation of the challenge #### User Story We need a button for each `Topic`. When we click on it, we delete all objects with this `Topic` in our database _(Fake DB in our case)_. Finally we display **All [topic] have been deleted** is everything was deleted successfully or **Error: deletion of some [topic] failed** if some deletions failed #### Constraints: We can only pass one object to our DB for deletion at the time. The DB will respond true if the data was successfully deleted and false otherwise. ### What you need to do The QA team reports a **bug**. The UI shows **All [topic] have been deleted** all the time, even if some deletions fail. 👉 Spot the bug and correct it. ### Submitting your work 1. Fork the project 2. clone it 3. npm install 4. `npx nx serve rxjs-pipe-bug` 5. _...work on it_ 6. Commit your work 7. Submit a PR with a title beginning with **Answer:11** that I will review and other dev can review. Rxjs pipe bug Rxjs pipe bug solution author _You can ask any question on_ twitter