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# add(in:)

Adds the indexes in an index range to the receiver.

```
func add(in range: NSRange)
```

## Parameters

`range`

Index range to add. Must be in the range `0 .. NSNotFound - 1`.

## Discussion

This method raises an [`rangeException`](/documentation/Foundation/NSExceptionName/rangeException) when `range` would add an index that exceeds the maximum allowed value for unsigned integers.

---

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