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# observationInfo

Returns a pointer that identifies information about all of the observers that are registered with the observed object.

```
var observationInfo: UnsafeMutableRawPointer? { get set }
```

## Return Value

A pointer that identifies information about all of the observers that are registered with the observed object, the options that were used at registration-time, and so on.

## Discussion

The default implementation of this method retrieves the information from a global dictionary of observed objects keyed by memory addresses.

For improved performance, both this property and [`observationInfo`](/documentation/ObjectiveC/NSObject-swift.class/observationInfo) can be overridden to store the opaque data pointer in an instance variable. Overrides of this property must not attempt to send messages to the stored data.

---

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