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# needsValueError(_:)

Returns a `restartPerform` error with context to request a value from the user for this
parameter and re-perform the intent with the new value.

```
final func needsValueError(_ dialog: IntentDialog? = nil) -> AppIntentError
```

## Parameters

`dialog`

a custom dialog that may be used when prompting the user for the value

## Return Value

an error that should be thrown within the intent `perform()` method.

---

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