首先，dom树模型与XSLT处理器所需的XPath模型有本质上的差别，这种差异会增加将一个模型映射成其它模型所带来的运行时成本。

First, the DOM tree model differs subtly from the XPath model needed by an XSLT processor, and this difference imposes run-time costs in mapping one model to the other.

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首先，dom树模型与XSLT处理器所需的XPath模型有本质上的差别，这种差异会增加将一个模型映射成其它模型所带来的运行时成本。

First, the DOM tree model differs subtly from the XPath model needed by an XSLT processor, and this difference imposes run-time costs in mapping one model to the other.

youdao