ActionError封装了单个错误消息。

ActionError encapsulates an individual error message.

youdao

正如您所见，这些数据远比单个错误代码有用，并且所需的错误诊断工作也更加少。

As you can see, this data is far more useful than a single error code and less work to troubleshoot.

youdao

通过使用子外壳，可以对整个块（而不是单个命令）的标准和错误输出进行集体重定向。

Using the subshell, you can collectively redirect their standard and error output for the entire block instead of for each individual command.

youdao

It would definitely be wrong if we were doing this because little sanity check if you just got the single one it means what instead?

如果我们这样做就是错误的,一个小检查,如果你用单个“=“，是什么意思？

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