Template:Short description Template:Infobox technology standard
XPointer is a system for addressing components of XML-based Internet media. It is divided among four specifications: a "framework" that forms the basis for identifying XML fragments, a positional element addressing scheme, a scheme for namespaces, and a scheme for XPath-based addressing. XPointer Framework is a W3C recommendation since March 2003.<ref name="W3C-xptr-framework" /><ref name="timelinehistory">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
The XPointer language is designed to address structural aspects of XML, including text content and other information objects created as a result of parsing the document. Thus, it could be used to point to a section of a document highlighted by a user through a mouse drag action.
During development, and until 2016, XPointer was covered by a royalty-free technology patent held by Sun Microsystems.<ref name="patents">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
Positional element addressingEdit
The element() scheme<ref name="xpointer-element-scheme">{{#invoke:citation/CS1|citation
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For instance, given the following fragment:
<syntaxhighlight lang="xml"> <foobar id="foo">
<bar/> <baz> <bom a="1"/> </baz> <bom a="2"/>
</foobar> </syntaxhighlight>
results as the following examples:
xpointer(id("foo")) => foobar
xpointer(/foobar/1) => bar
xpointer(//bom) => bom (a=1), bom (a=2)
element(/1/2/1) => bom (a=1) (/1 descend into first element (foobar),
/2 descend into second child element (baz),
/1 select first child element (bom))