This step ensures that even an empty element (one with no existing text node) is updated.

这一步确保即使是空元素(即不具有现有文本节点的元素)，也进行更新。

youdao

If text is omitted and there is no existing text value to replace, the update command fails.

如果省略了text且不存在要替换的现有文本值，更新命令就会失败。

youdao

The question marks (?) in the expression are replaced with the existing text value of the target node.

表达式中的问号(？)将由目标节点的现有文本值替换。

youdao

Nina also includes a range of existing Nuance text-to-speech voices, and Nuance can develop a custom TTS voice for an optional development fee.

ENGADGET: Voice assistant 'Nina' lets any app obey commands, makes speech your password

The source code for the existing Silent Text version is here and the company tells me that the new Silent Text source code will be released sometime in March or April after confirming legal issues such as licenses for third-party libraries.

FORBES: Pressure Increases On Silent Circle To Release Application Source Code

Existing technology like text-to-speech, voice command, Bluetooth hands-free calling and traffic services also helps alleviate driver distraction to avoid potentially dangerous situations.

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