Review Gap Fill

XSLT is a language for XML documents into various kinds of output: XML, XHTML, HTML and . XSLT itself is expressed in XML, which means that it can be just like any other XML file. XSLT itself is very simple (it has a very small set of tags), but its power and expressiveness derive from its use of , a sophisticated language which is used for the XML tree structure. XPath allows you to move from any node in the tree to any other node, along a series of (::, child::, ancestor::, descendant::, preceding::, following::, preceding-sibling:: and following-sibling::).

A basic XSLT stylesheet consists of a small number of core elements, including the root element (<>), <xsl:output>, and <xsl:template>. Most stylesheets include a long list of <> elements, each of which contains a collection of rules to handle a particular node or set of nodes in the tree. One element causes all the processing to start: </>.

Right now, there are three versions of XSLT. Version is widely supported by many processors, but it has serious limitations. Version is much more sophisticated, but so far there is only one good, free processor which supports it: . Version 3 is still in development, although Saxon 9 has some support for its new features.

One of the difficulties you will encounter when learning XSLT is that it's not enough just to learn the XPath and XSLT code; to make useful output, you also need to learn (to make the output document), (to style the output document), and possibly also (to make the document interactive).