com.saxonica.extra
Class DynamicFunctionCall

java.lang.Object
  net.sf.saxon.expr.ComputedExpression
      net.sf.saxon.expr.FunctionCall
          net.sf.saxon.functions.SystemFunction
              com.saxonica.extra.DynamicFunctionCall

All Implemented Interfaces:

Container, Expression, InstructionInfoProvider, java.io.Serializable, javax.xml.transform.SourceLocator

public class DynamicFunctionCall

extends SystemFunction

This class implements the extension function saxon:call(), which calls a FirstClassFunction previously set up using saxon:function(). The first argument is the FirstClassFunction object, the remaining arguments are the parameters to be supplied in the call.

See Also:

Serialized Form

Field Summary

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

operation

Fields inherited from class net.sf.saxon.expr.FunctionCall

argument

Fields inherited from class net.sf.saxon.expr.ComputedExpression

locationId, staticProperties

Fields inherited from interface net.sf.saxon.expr.Expression

EVALUATE_METHOD, ITERATE_METHOD, PROCESS_METHOD

Constructor Summary

DynamicFunctionCall()

Method Summary

protected SequenceType	getRequiredType(int arg) Get the required type of the nth argument
SequenceIterator	iterate(XPathContext context) Return an Iterator to iterate over the values of a sequence.
Expression	preEvaluate(StaticContext env) Pre-evaluate a function at compile time.

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

addContextDocumentArgument, checkArguments, computeCardinality, computeSpecialProperties, display, getDetails, getErrorCodeForTypeErrors, getItemType, main, makeSystemFunction, setDetails, useContextItemAsDefault

Methods inherited from class net.sf.saxon.expr.FunctionCall

checkArgumentCount, getDisplayName, getFunctionNameCode, getNumberOfArguments, iterateSubExpressions, optimize, promote, setArguments, setFunctionNameCode, simplify, simplifyArguments, typeCheck

Methods inherited from class net.sf.saxon.expr.ComputedExpression

adoptChildExpression, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, dynamicError, dynamicError, effectiveBooleanValue, evaluateAsString, evaluateItem, getCardinality, getColumnNumber, getConstructType, getDependencies, getExecutable, getHostLanguage, getImplementationMethod, getInstructionInfo, getIntrinsicDependencies, getLineNumber, getLocationId, getLocationProvider, getParentExpression, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, hasBadParentPointer, markTailFunctionCalls, process, resetStaticProperties, setLocationId, setParentExpression, suppressValidation, typeError, typeError

Methods inherited from class java.lang.Object

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

Constructor Detail

DynamicFunctionCall

public DynamicFunctionCall()

Method Detail

preEvaluate

public Expression preEvaluate(StaticContext env)
                       throws XPathException

Pre-evaluate a function at compile time. Pre-evaluation of this function is not allowed because it requires access to the dynamic context

Overrides:

preEvaluate in class FunctionCall

Throws:

XPathException

iterate

public SequenceIterator iterate(XPathContext context)
                         throws XPathException

Return an Iterator to iterate over the values of a sequence. The value of every expression can be regarded as a sequence, so this method is supported for all expressions. This default implementation handles iteration for expressions that return singleton values: for non-singleton expressions, the subclass must provide its own implementation.

Specified by:

iterate in interface Expression

Overrides:

iterate in class ComputedExpression

Parameters:

context - supplies the context for evaluation

Returns:

a SequenceIterator that can be used to iterate over the result of the expression

Throws:

XPathException - if any dynamic error occurs evaluating the expression

getRequiredType

protected SequenceType getRequiredType(int arg)

Get the required type of the nth argument

Overrides:

getRequiredType in class SystemFunction