Cheat Sheet
| Question | Core Idea | Senior Signal |
|---|---|---|
| Q126 | Coercion | Parse external data explicitly and treat valid falsy values carefully. |
| Q127-Q128 | Modern syntax | Destructuring and spread are shallow; optional chaining and nullish coalescing protect only nullish cases. |
| Q129 | Events | Subscriptions need clear payloads, timing, errors, and unsubscribe behavior. |
| Q130 | Streams | Async iterables deliver values over time; backpressure protects memory and responsiveness. |