Code reviewHardcr-g185

Subject Memory leak listenersLevel Senior–Staff~24 minCommon in Networking & APIs interviewsIndustries Software development

Question

Review this React TypeScript hook.

What a strong answer looks like

Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix — specific and kind.

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Code to reviewtsx

1function useLiveFeed(url: string) {2  const [msgs, setMsgs] = useState<Msg[]>([]);3 4  useEffect(() => {5    const ws = new WebSocket(url);6    ws.onmessage = (e) => setMsgs((m) => [...m, JSON.parse(e.data)]);7    return () => ws.onmessage = null;8  }, [url]);9 10  return msgs;11}

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