XSLT and XPath
For more details on this topic, see XPath.XSLT uses XPath to identify subsets of the source document tree and perform calculations. XPath also provides a range of functions, which XSLT itself further augments.
XSLT 1.0 uses XPath 1.0. XSLT 2.0 uses XPath 2.0. Both specifications were published on the same date.
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