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# init(capacity:)

Creates an empty data buffer of a specified size.

```
init(capacity: Int)
```

## Parameters

`capacity`

The size of the data.

## Discussion

This initializer doesn’t necessarily allocate the requested memory right away. `Data` allocates additional memory as needed, so `capacity` simply establishes the initial capacity. When it does allocate the initial memory, though, it allocates the specified amount.

This method sets the `count` of the data to 0.

If the capacity specified in `capacity` is greater than four memory pages in size, this may round the amount of requested memory up to the nearest full page.

---

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