init(installedSource:target:)
Creates a translation session to translate between a given source and target language already installed on device.
Declaration
convenience init(installedSource source: Locale.Language, target: Locale.Language?)Discussion
If one or both of the languages aren’t installed on the device already, attempting to translate will throw errors. In order to get the person’s permission to download languages that aren’t already installed, translate using a TranslationSession provided by translationTask(_:action:) or translationTask(source:target:action:) .