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# environment(_:stateDidChangeFromOldState:)

Called when there has been a change in the environment.

```
optional func environment(_ environment: LAEnvironment, stateDidChangeFromOldState oldState: LAEnvironment.State)
```

## Parameters

`oldState`

The old environment state (before update)

## Discussion\discussion Invoked on a queue private to LocalAuthentication framework. At the moment of invocation of this method,
@c LAEnvironment.state already contains the new updated state.

---

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