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# removeAll(keepingCapacity:)

Removes all elements from the collection.

```
mutating func removeAll(keepingCapacity keepCapacity: Bool = false)
```

## Parameters

`keepCapacity`

Pass `true` to request that the collection
avoid releasing its storage. Retaining the collection’s storage can
be a useful optimization when you’re planning to grow the collection
again. The default value is `false`.

## Discussion

Calling this method may invalidate any existing indices for use with this
collection.

> Complexity: O(*n*), where *n* is the length of the collection.

---

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