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# setCapacity(_:)

Grow or shrink the capacity of a unique array instance without discarding
its contents.

```
mutating func setCapacity(_ newCapacity: Int)
```

## Discussion

This operation replaces the array’s storage buffer with a newly allocated
buffer of the specified capacity, moving all existing elements
to its new storage. The old storage is then deallocated.

> Complexity: O(`count`)

---

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