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# init(indexesIn:)

Initializes an allocated [`NSIndexSet`](/documentation/Foundation/NSIndexSet) object with an index range.

```
init(indexesIn range: NSRange)
```

## Parameters

`range`

An index range. Must be in the range `0 .. NSNotFound - 1`..

## Return Value

Initialized [`NSIndexSet`](/documentation/Foundation/NSIndexSet) object with `indexRange`.

## Discussion

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

The resulting index set has a [`firstIndex`](/documentation/Foundation/NSIndexSet/firstIndex) equal to the `location` of `indexRange`, and a [`count`](/documentation/Foundation/NSIndexSet/count) equal to the `length` of `indexRange`. Specifying a zero-length range results in an empty index set.

This method is a designated initializer for [`NSIndexSet`](/documentation/Foundation/NSIndexSet).

## See Also

[`+  indexSetWithIndexesInRange:`](/documentation/Foundation/NSIndexSet/indexSetWithIndexesInRange:)

Creates an index set with an index range.


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