The integrity function is not optional.

完整性功能不是可选功能。

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You can pass an optional data object and callback function if you need them.

如果需要的话，您还可以传递一个可选的数据对象和回调函数。

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An optional completion function is available to preemptively complete the task, even if all of the subtasks are not yet completed.

可以使用可选的完成功能提前完成任务，即使子任务还没有全部完成。

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Among the functions unique in the MINI segment are access to the GoogleTM local search and GoogleTM Send to Car services and reception of user-definable RSS news feeds, the content of which is displayed on the on-board monitor and can be read out using the optional voice output function.

ENGADGET: Mini Cooper Connected app adjusts music based on driving style, stops when airbags deploy