FunctX XQuery Functions

FunctX XQuery Function Library > XML Nodes > Hierarchical Relationships >

fn:root

The root of the tree that contains the argument

Description

The fn:root function returns a document node if the $arg node is part of a document, but it may also return an element if the $arg node is not part of a document.

Calling the fn:root function is similar to starting a path with / or /. It is more flexible in that it can appear anywhere in a path or other expression. Also, unlike starting with a path with /, the fn:root function does not require the root to be a document node; it could be an element in the case of a document fragment.

This description is © Copyright 2007, O'Reilly Media. It is excerpted from the book XQuery by Priscilla Walmsley, O'Reilly, 2007. For a complete explanation of this function, please refer to Appendix A of the book.

Arguments and Return Type

Name	Type	Description
`$arg`	`node()?`	the node to find the root of
return value	`node()?`

Examples

`let $in-xml :=`	<a><x>123</x></a>
`return`

XQuery Example	Results
`root( doc('http://www.functx.com/input/order.xml') //item[1])`	The document node of order.xml
`root($in-xml/x)`	`<a> <x>123</x> </a>`

History

Published On	Last Updated	Contributor(s)
2006-06-27	2007-02-26	W3C, XQuery 1.0 and XPath 2.0 Functions and Operators, http://www.w3.org/TR/xpath-functions/

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