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# replaceObject(at:with:)

Replaces the object at `index` with `anObject`.

```
func replaceObject(at index: Int, with anObject: Any)
```

## Parameters

`index`

The index of the object to be replaced. This value must not exceed the bounds of the array.
  
  > Important:
  > Raises an `NSRangeException` if `index` is beyond the end of the array.

`anObject`

The object with which to replace the object at index `index` in the array. This value must not be `nil`.
  
  > Important:
  > Raises an `NSInvalidArgumentException` if `anObject` is `nil`.

## See Also

[`-  removeObjectsAtIndexes:`](/documentation/Foundation/NSMutableArray/removeObjects(at:))

Removes the objects at the specified indexes from the array.

[`-  setObject:atIndexedSubscript:`](/documentation/Foundation/NSMutableArray/setObject:atIndexedSubscript:)

Replaces the object at the index with the new object, possibly adding the object.

[`-  removeObjectAtIndex:`](/documentation/Foundation/NSMutableArray/removeObject(at:))

Removes the object at `index` .

[`-  insertObject:atIndex:`](/documentation/Foundation/NSMutableArray/insert(_:at:)-5dbx5)

Inserts a given object into the array’s contents at a given index.


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