com.saxonica.extra
Class DynamicFunctionCall

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

All Implemented Interfaces:

Serializable, SourceLocator, EvaluableItem, SequenceIterable, InstructionInfoProvider

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.expr.Expression

EVALUATE_METHOD, ITERATE_METHOD, PROCESS_METHOD

Constructor Summary

DynamicFunctionCall()

Method Summary

SequenceIterator	iterate(XPathContext context) Return an Iterator to iterate over the values of a sequence.
Expression	preEvaluate(ExpressionVisitor visitor) Pre-evaluate a function at compile time.

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

addDocToPathMap, checkArguments, computeCardinality, computeSpecialProperties, copy, getDetails, getErrorCodeForTypeErrors, getItemType, makeSystemFunction, optimize, setDetails

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

addExternalFunctionCallToPathMap, equals, explain, getArguments, getDisplayName, getFunctionName, getNumberOfArguments, hashCode, iterateSubExpressions, promote, replaceSubExpression, setArguments, setFunctionName, simplify, toString, typeCheck

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

addToPathMap, adoptChildExpression, checkPermittedContents, computeDependencies, computeStaticProperties, display, doPromotion, effectiveBooleanValue, evaluateAsString, evaluateItem, explain, findParentOf, getCardinality, getColumnNumber, getContainer, getDependencies, getExecutable, getHostLanguage, getImplementationMethod, getInstructionInfo, getIntrinsicDependencies, getLineNumber, getLocationId, getLocationProvider, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, hasLoopingSubexpression, implementsStaticTypeCheck, iterateEvents, markTailFunctionCalls, process, setContainer, setFiltered, setFlattened, setLocationId, staticTypeCheck, suppressValidation

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

DynamicFunctionCall

public DynamicFunctionCall()

Method Detail

preEvaluate

public Expression preEvaluate(ExpressionVisitor visitor)
                       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

Parameters:

visitor - an expression visitor an expression visitor

Returns:

the result of the early evaluation, or the original expression, or potentially a simplified expression

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 SequenceIterable

Overrides:

iterate in class Expression

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