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# AUParameterRecordingObserver

A block called to record parameter changes as automation events.

```
typealias AUParameterRecordingObserver = (Int, UnsafePointer<AURecordedParameterEvent>) -> Void
```

## Discussion

The block takes the following parameters:

- numberEvents: The number of events being delivered.
- events: The events being delivered.

## See Also

[`-  tokenByAddingParameterRecordingObserver:`](/documentation/AudioToolbox/AUParameterNode/token(byAddingParameterRecordingObserver:))

Adds a recording observer for a single parameter or all parameters in a group.


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