---
title: "transformingChanges(_:)"
framework: foundation
role: symbol
role_heading: Instance Method
path: "foundation/nsorderedcollectiondifference/transformingchanges(_:)"
---

# transformingChanges(_:)

Create a new ordered collection difference by mapping over this difference’s members, processing the change objects with the block provided.

## Declaration

```swift
func transformingChanges(_ block: (NSOrderedCollectionChange) -> NSOrderedCollectionChange) -> CollectionDifference<Any>
```

## Parameters

- `block`: A block receives an ordered collection change and returns an updated change.

## Return Value

Return Value A new ordered collection difference.