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JavaScript
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Fundamentals · easy
18. Optional chaining
Read deep fields safely.
Write `tokenName(tx)` returning `tx.token.name` or `"unknown"` when missing, using `?.`.
Required in your answer:
?.
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Runs in a sandboxed worker
function tokenName(tx) { // TODO }
Output appears here.
← 17. Truthiness & defaults
19. Sorting →