在执行表达式时，计算表达式并将结果赋值给模式。

When the expression is executed, the expression is evaluated, and the results assigned to the pattern.

youdao

这个函数类似于顶级XPath判断，它从XSLT接收当前节点，并执行表达式判断，如清单6所示。

This function, similar to the top-level XPath evaluation, passes in the current node from the XSLT and evaluates the expression against that, as in Listing 6.

youdao

VALUES…into语句允许执行SQL表达式，并将结果返回至变量。

The VALUES... into statement allows an SQL expression to be executed and to return the result into variables.

youdao

And so, in fact, if I wanted the other version of it, in fact, if I do this right, 23 it's going to give me 23 because it does the multiplication first, if I wanted the other version of it, Python I need to tell it that, by using, excuse me, parentheses.

因此，实际上，如果我想换种做法，实际上，如果我去执行这个表达式，返回值是3,因为乘法会被优先执行，如果我需要换种做法，我需要告诉，用括号来告诉它。

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