Editing XPointer (section)

== Positional element addressing ==
The <code>element()</code> scheme<ref name="xpointer-element-scheme">{{Cite web|url=https://www.w3.org/TR/xptr-element/|title=XPointer element() Scheme|publication-date=2003-03-23|access-date=2021-04-08|collaboration=W3C XML Linking Working Group|website=W3C|publisher=W3C|editor-first1=Paul|editor-last1=Grosso|editor-first2=Eve|editor-last2=Maler|editor-first3=Jonathan|editor-last3=Marsh|editor-first4=Norman|editor-last4=Walsh}}</ref> introduces positional addressing of child elements.  This is similar to a simple XPath address, but subsequent steps can only be numbers representing the position of a descendant relative to its branch on the tree.

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))