Returns a path expression that can be used to select the supplied node relative to the root of its containing document.
fn:path
( xs:string?
fn:path
( $arg
as node()?
xs:string?
The behavior of the function if the argument is omitted is exactly the same as if the
context item (.
) had been passed as the argument.
If $arg
is the empty sequence, the function returns the empty sequence.
If $arg
is a document node, the function returns the string
"/"
.
Otherwise, the function returns a string that consists of a sequence of steps, one
for each ancestor-or-self of $arg
other than the root node. This string is
prefixed by "Q{http://www.w3.org/2005/xpath-functions}root()"
if the root
node is not a document node. Each step consists of the character "/"
followed by a string whose form depends on the kind of node selected by that step, as
follows:
For an element node,
Q{uri}local[position]
,
where
uri
is the namespace URI of the node name or the
empty string if the node is in no namespace,
local
is
the local part of the node name, and
position
is an
integer representing the position of the selected node among its like-named
siblings.
For an attribute node:
if the node is in no namespace, @local
, where
local
is the local part of the node name
otherwise, @Q{uri}local
, where
uri
is the namespace URI of the node name,
and
local
is the local part of the node name
For a text node: text()[position]
where
position
is an integer representing the position
of the selected node among its text node siblings
For a comment node: comment()[position]
where
position
is an integer representing the position
of the selected node among its comment node siblings
For a processing-instruction node:
processing-instruction(local)[position]
where
local
is the name of the processing instruction
node and
position
is an integer representing the
position of the selected node among its like-named processing-instruction node
siblings
For a namespace node:
If the namespace node has a name:
namespace::prefix
, where
prefix
is the local part of the name of the
namespace node (which represents the namespace prefix).
If the namespace node has no name (that is, it represents the default
namespace):
namespace::*[Q{http://www.w3.org/2005/xpath-functions}local-name()=""]
let $e :=
The expression fn:path($e)
returns '/'
.
The expression fn:path($e/*:p)
returns '/Q{http://example.com/one}p[1]'
.
The expression fn:path($e/*:p/@xml:lang)
returns '/Q{http://example.com/one}p[1]/@Q{http://www.w3.org/XML/1998/namespace}lang'
.
The expression fn:path($e/*:p/@author)
returns '/Q{http://example.com/one}p[1]/@author'
.
The expression fn:path($e/*:p/*:br[2])
returns '/Q{http://example.com/one}p[1]/Q{http://example.com/one}br[2]'
.
The expression fn:path($e//text()[starts-with(normalize-space(),
'Tochter')])
returns '/Q{http://example.com/one}p[1]/text()[2]'
.
let $emp :=
The expression fn:path($emp)
returns 'Q{http://www.w3.org/2005/xpath-functions}root()'
.
The expression fn:path($emp/@xml:id)
returns 'Q{http://www.w3.org/2005/xpath-functions}root()/@Q{http://www.w3.org/XML/1998/namespace}id'
.
The expression fn:path($emp/empnr)
returns 'Q{http://www.w3.org/2005/xpath-functions}root()/Q{}empnr[1]'
.
The following errors may be raised when $arg
is omitted:
If the context item is absent, dynamic error
If the context item is not a node, type error .