我们希望在您开发自已的Web服务项目时为您提供一些有用信息。

We hope you find this useful as you develop your Web services projects.

youdao

在到目前为止的示例中，我们一直在使用没有包含一些有用信息的“ z sh % ”提示符。

In the examples so far, we have been using a prompt of "ZSH %", which is not terribly informative.

youdao

处于社交圈中的人们可能会参与一些有用信息的传播，比如哪些地方有吃的，或者好的投资选择等等。

People in the middle of a social network could be privy to useful gossip, such as the location of food or good investment choices.

youdao

But notice what this does. The first thing it does is, it says, let's check and make sure x is greater than or equal to 0. If it isn't, notice what's going to happen. None of that block is going to get executed, and it's going to come down here and print out a useful piece of information, which says, hey, you gave me a negative number. I don't know how to do this.

做的是和以前一样的事情,但是注释它做了什么，第一件做的事情就是,程序说，要去检查并且确信x是大于等于0的，如果不是的话，请注意会发生什么,下面的代码都不会被执行,程序会到这里来然后显示一些有用的信息,信息会说，嘿，你给了我一个负数,我不知道该怎么弄这个了。

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