Where is xpath "element()" documented?

Question

I just stumpled upon this xpath function(?) and I assume it is functioning like node(), etc. Hoever, I simply cannot seem to find any documentation.

Example

<xsl:apply-templates select="./element()"/>

Im using latest version of saxon processor.

Answer 1

As others have said, it is documented in the XPath specification. It was introduced in XPath 2.0. In an axis step, and in a pattern, it is (nearly always) equivalent to *, but it can also be used as an item type, for example

<xsl:if test="$param instance of element()">

<xsl:function name="f:parent" as="element()?">