Cheat Sheet
| Question | Core Idea | Senior Signal |
|---|---|---|
| Q116 | Memory leaks | Garbage collection keeps reachable objects, so leaks are accidental retaining paths. |
| Q117 | Cancellation | Promises do not cancel work; AbortController provides a signal-based cancellation channel. |
| Q118 | Copying | Object spread is shallow, JSON copy is limited, and structuredClone is richer but not universal. |
| Q119-Q120 | Errors and functions | Classify errors for behavior and use functional patterns where they improve predictability. |