---
title: CFArrayApplierFunction
framework: corefoundation
role: symbol
role_heading: Type Alias
path: corefoundation/cfarrayapplierfunction
---

# CFArrayApplierFunction

Prototype of a callback function that may be applied to every value in an array.

## Declaration

```swift
typealias CFArrayApplierFunction = (UnsafeRawPointer?, UnsafeMutableRawPointer?) -> Void
```

## Parameters

- `value`: The current value in an array.
- `context`: The program-defined context parameter given to the applier function.

## Discussion

Discussion This callback is passed to the CFArrayApplyFunction(_:_:_:_:) function, which iterates over the values in an array and applies the behavior defined in the applier function to each value in an array.

## See Also

### Callbacks

- [CFArrayCopyDescriptionCallBack](corefoundation/cfarraycopydescriptioncallback.md)
- [CFArrayEqualCallBack](corefoundation/cfarrayequalcallback.md)
- [CFArrayReleaseCallBack](corefoundation/cfarrayreleasecallback.md)
- [CFArrayRetainCallBack](corefoundation/cfarrayretaincallback.md)