XPath expressions

XPath is embedded in XSLT 1.0 and in USoft Blend. It is a general expression language with node set expressions as its specialising characteristic. Node set expressions are evaluated relative to a location in an XML document being traversed. They allow you to point from that context to nodes in the XML document in a set-oriented fashion.

Type of XPath expression	Returns data type	Explanation	Examples
xpath-expression (for short: xpath)	Any	Any XPath expression. All the items in this table subset xpath-expression.
node set-expression	Node set	An XPath expression representing a node set.	node() pc:* /parent/child[1]
absolute-location-path	Node set	A node set expression that DOES start with the / character	/parent/child[1]
relative-location-path	Node set	A node set expression that does NOT start with the / character	node() pc:*
boolean	Boolean	A value expressing the concept of either "true" or "false".	$is-valid true()
string	String	A sequence of Unicode characters.	'ABC110' "My variable value"
number	Number	A floating-point number.	98 24.7
function-call	Any	A parenthesised expression that calls either a USoft Blend function or an XPath function.	dates:ShowInputFormats() concat('A', 'B')
variable-reference	Any	A placeholder representing a variable.	$myvar