net.sf.saxon.functions

Class ElementAvailable

java.lang.Object

net.sf.saxon.om.AbstractItem

net.sf.saxon.functions.AbstractFunction

net.sf.saxon.functions.SystemFunction

net.sf.saxon.functions.ElementAvailable

All Implemented Interfaces:

Callable, Function, GroundedValue, Item, Sequence

public class ElementAvailable
extends SystemFunction

This class supports the XSLT element-available function. Note that when running in a 2.0 processor, it only looks for XSLT 2.0 instructions; but when running in a 3.0 processor, it recognizes all elements in the XSLT namespace whether or not they are classified as instructions.

Constructor Summary

Constructors

Constructor and Description
ElementAvailable()

Method Summary

Modifier and Type	Method and Description
BooleanValue	call(XPathContext context, Sequence[] arguments) Evaluate the expression
int	getSpecialProperties(Expression[] arguments) Special-case for element-available('xsl:evaluate') which may be dynamically-disabled, and the spec says that this should be assessed at run-time.
static boolean	isSaxonJSElement(int fp)
static boolean	isXslt20Instruction(int fp)
static boolean	isXslt30Element(int fp)

Methods inherited from class net.sf.saxon.functions.SystemFunction

dependsOnContextItem, dynamicCall, equals, export, exportAdditionalArguments, exportAttributes, fixArguments, getArity, getCardinality, getCompilerName, getContextNode, getDescription, getDetails, getErrorCodeForTypeErrors, getFunctionItemType, getFunctionName, getIntegerBounds, getNetCost, getOperandRoles, getRequiredType, getResultItemType, getResultItemType, getRetainedStaticContext, getStaticBaseUriString, getStreamerName, importAttributes, isTrustedResultType, makeCall, makeFunction, makeFunctionCall, makeOptimizedFunctionCall, resultIfEmpty, setArity, setDetails, setRetainedStaticContext, supplyTypeInformation, typeCheckCaller

Methods inherited from class net.sf.saxon.functions.AbstractFunction

atomize, deepEquals, effectiveBooleanValue, getAnnotations, getStringValue, getStringValueCS, isArray, isMap, makeNewContext, simplify, typeCheck

Methods inherited from class net.sf.saxon.om.AbstractItem

getLength, head, isStreamed, itemAt, iterate, reduce, subsequence

Methods inherited from class java.lang.Object

clone, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface net.sf.saxon.om.Function

iterate

Methods inherited from interface net.sf.saxon.om.Item

head

Methods inherited from interface net.sf.saxon.om.GroundedValue

getLength, head, itemAt, reduce, subsequence

Constructor Detail

ElementAvailable

public ElementAvailable()

Method Detail

isXslt20Instruction

public static boolean isXslt20Instruction(int fp)

isXslt30Element

public static boolean isXslt30Element(int fp)

isSaxonJSElement

public static boolean isSaxonJSElement(int fp)

getSpecialProperties

public int getSpecialProperties(Expression[] arguments)

Special-case for element-available('xsl:evaluate') which may be dynamically-disabled, and the spec says that this should be assessed at run-time. By indicating that the effect of the function depends on the run-time environment, early evaluation at compile time is suppressed.

Overrides:

getSpecialProperties in class SystemFunction

Parameters:

arguments - the actual arguments supplied in a call to the function

call

public BooleanValue call(XPathContext context,
                         Sequence[] arguments)
                  throws XPathException

Evaluate the expression

Parameters:

context - the dynamic evaluation context

arguments - the values of the arguments, supplied as SequenceIterators

Returns:

the result of the evaluation, in the form of a SequenceIterator

Throws:

XPathException - if a dynamic error occurs during the evaluation of the expression