本文中的示例演示了如何使用XML变量进行声明、赋值和测试。

The examples in this article illustrated how to use an XML variable for declaring, assigning, and testing values.

youdao

let：使用let可以为变量赋值，但是(很快将看到)和其他flwor子句相比，let用的比较少。

Let: you assign values to variable with let, although (as you'll soon see) you won't use let as often as you use the other FLWOR clauses.

youdao

这让我们可以迅速获得信息，像在区域中为哪个变量赋值、引用了哪个变量以及该变量是否包含在某个跳转和返回的声明中。

This allows one to quickly get information such as which variables are assigned in a region, which are referenced, and if it contains any jump or return statements.

youdao

Did the same thing with c p 2, 2 2 0 Again, remind you, c p 2 is a different instance of this data type.

建立了一个x变量，我也把它赋值为，因此cp1内置有了x和y值,然后对cp2做同样的操作。

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