These transformations group a set of mappings based on a given XPath expression condition.

这些转换根据给定的 XPath 表达式条件对映射进行分组。

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Each link may be associated with a transition condition, which is a Boolean expression using values in the different containers of the process.

每个link可与一个转变条件相关联，这个条件是使用流程的不同容器中的值的布尔表达式。

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When the XPath expression is evaluated, the value of the condition will be determined based on the return value of the expression as shown in Table 5.

在计算XPath表达式时，条件的值将根据表达式的返回值确定，如表5所示。

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So we can now take this expression and rewrite it under the condition of du is equal to zero.

我们利用这个公式,并在du=0的条件下将它重写。

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