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# CGFunctionRetain

Increments the retain count of a function object.

```
extern CGFunctionRefCGFunctionRetain(CGFunctionRef function);
```

## Parameters

`function`

The function object to retain.

## Discussion

This function is equivalent to <doc://com.apple.documentation/documentation/CoreFoundation/CFRetain>, except that it does not cause an error if the `function` parameter is `nil`.

---

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