Harden safe localStorage cache
Hard JavaScript arena: browser storage, JSON parsing, TTLs, and schema checks
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Missing prerequisites: javascript-easy-dom-storage
A dashboard caches preferences but must survive corrupted localStorage values. You are working inside a modern JavaScript application, and the arena only clears when the result is safe, deterministic, and explainable.
Learn to apply browser storage, JSON parsing, TTLs, and schema checks in a modern JavaScript application while explaining the invariant, safety constraints, and hidden edge cases.
- Demonstrates browser storage, JSON parsing, TTLs, and schema checks
- Handles the visible sample and hidden edge cases
- Keeps output deterministic and explainable
- Avoids unsafe dynamic execution
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