Time: 0:00
Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).
This bug belongs to the type errors pattern
Totals that concatenate, sorts that put 10 before 9, comparisons that refuse to run.
What went wrong: typeof null is "object", so null goes into the object branch.
The fix: add if (value === null) return "null"; as the first line.
Remember: typeof cannot tell null from an object. Check === null first.
The pattern behind it: type errors.
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<iframe src="https://trybughunt.com/embed/edc35cf2-1107-497b-9ad6-c44048eb3990" title="Debugging challenge: Type checker says null is an object" width="100%" height="580" loading="lazy" style="border:1px solid #d4d4d8;border-radius:12px;max-width:760px"></iframe>
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