saxon:evaluate
Allows XPath expressions to be constructed and evaluated dynamically at run-time.
evaluate($xpath as xs:string, $param1 as item()*, $param2 as item()*, $param3 as item()*) ➔ item()*
Arguments | |||
| $xpath | xs:string | The XPath expression to be evaluated |
| $param1 | item()* | The value to be bound to $p1 |
| $param2 | item()* | The value to be bound to $p2 |
| $param3 | item()* | The value to be bound to $p3 ... |
Result | item()* | ||
Namespace
http://saxon.sf.net/
Notes on the Saxon implementation
Available since before Saxon 7.2. Note that an xsl:evaluate instruction with similar functionality is available as a standard feature in XSLT 3.0.
Details
The number of arguments is variable (1 or more).
The supplied string must contain an XPath expression. The result of the function is the result of evaluating the XPath expression. This is useful where an expression needs to be constructed at run-time or passed to the stylesheet as a parameter, for example where a sort key is determined dynamically.
The static context for the expression includes all the in-scope namespaces, types, and
functions from the calling stylesheet or query. It does not include any variables
from the calling environment. The base URI and default function namespace are inherited
from the calling environment. The default namespace for elements and types is taken from
the value of the xpath-default-namespace attribute in the stylesheet, if
present.
The expression may contain references to variables $p1, $p2,
etc., and the values of these variables may be supplied in the second, third, and
subsequent arguments to the saxon:evaluate() call.
The function saxon:evaluate(string) is shorthand for
saxon:eval(saxon:expression(string)). For the rules governing what may
and may not appear in the expression, see the details of
saxon:expression.
See also saxon:evaluate-node(), which is a similar function intended for
evaluating XPath expressions contained in a source document.