JS Built-ins
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ArrayArray.prototype.withintermediate

Verify No Mutation

📖 Usage Example
const original = [1, 2, 3]
const updated = original.with(0, 99)
original  // → [1, 2, 3]  (unchanged)
updated   // → [99, 2, 3]

with() never mutates the source array — it always returns a new array with the change applied.

Array.prototype.with — Immutability

with() does not mutate the original array. It always returns a new array.

Implement withNoMutation that calls arr.with(0, 99) but returns the original arr. The original should be unchanged.

💡 Hints (2)
  • • `with()` is a non-mutating method — calling it does not change the original array.
  • • The return value of `arr.with(0, 99)` is a new array, not `arr`.