Saxon.Api

 

 

Saxon.Api

Class XdmFunctionItem

Direct Known Subclasses
XdmArray, XdmMap
public class XdmFunctionItem
extends XdmItem

The class XdmFunctionItem represents an item in an XDM sequence that holds a function.

Note that there is no guarantee that every XdmValue comprising a single function item will be an instance of this class. To force this, use the Simplify property of the XdmValue.

There are two ways of creating an instance of this class: either evaluate an XPath or XQuery or XSLT expression that returns a function item, or use the method Processor.GetSystemFunction to obtain a built-in system function.

Arrays and Maps are functions, so the types XdmArray and XdmMap extend XdmFunctionItem.

Property Summary
 int Arity

The arity of the function, that is, the number of arguments it expects

 QName FunctionName

The name of the function, as a QName

 

Method Summary
 XdmValue Invoke (XdmValue[] arguments, Processor processor)

Invoke the function

 bool IsAtomic ()

Determine whether the item is an atomic value

 

Property Detail

Arity

public int Arity {get; }

The arity of the function, that is, the number of arguments it expects

Returns:

The number of arguments that the function takes

FunctionName

public QName FunctionName {get; }

The name of the function, as a QName

Returns:

The name of the function. The result will be null if the function is anonymous.

Method Detail

Invoke

public XdmValue Invoke(XdmValue[] arguments,
Processor processor)

Invoke the function

Parameters:

arguments - The arguments to the function
processor - The Saxon processor, used to provide context information

Returns:

The result of calling the function

IsAtomic

public override bool IsAtomic()

Determine whether the item is an atomic value

Returns:

false (a function item is not an atomic value)