CompileTimeFunction

java.lang.Object
- net.sf.saxon.expr.Expression
- - net.sf.saxon.expr.FunctionCall
  - - net.sf.saxon.functions.SystemFunction
    - - net.sf.saxon.functions.CompileTimeFunction

All Implemented Interfaces:

java.io.Serializable, javax.xml.transform.SourceLocator, LocationProvider, SaxonLocator, EvaluableItem, SequenceIterable, InstructionInfo, org.xml.sax.Locator

Direct Known Subclasses:

Data, DefaultCollation, StaticBaseURI, Unordered
```
public abstract class CompileTimeFunction
extends SystemFunction
```
Abtract class representing a function call that is always rewritten at compile-time: it can never be executed

See Also:

Serialized Form

Field Summary
- Fields inherited from class net.sf.saxon.expr.Expression
  EVALUATE_METHOD, ITERATE_METHOD, locationId, PROCESS_METHOD, staticProperties
- Fields inherited from class net.sf.saxon.expr.FunctionCall
  argument
- Fields inherited from class net.sf.saxon.functions.SystemFunction
  operation

Constructor Summary

Constructors
Constructor Description

CompileTimeFunction()

Constructors
Constructor	Description
`CompileTimeFunction()`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`Item`	`evaluateItem(XPathContext c)`	Evaluate as a single item
`SequenceIterator`	`iterate(XPathContext c)`	Iterate over the results of the function
`Expression`	`preEvaluate(ExpressionVisitor visitor)`	preEvaluate: this method suppresses compile-time evaluation by doing nothing.

Methods inherited from class net.sf.saxon.expr.Expression
addToPathMap, adoptChildExpression, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, display, doPromotion, dynamicError, effectiveBooleanValue, evaluateAsString, evaluatePendingUpdates, explain, findParentOf, getCardinality, getColumnNumber, getColumnNumber, getConstructType, getContainer, getDependencies, getExecutable, getHostLanguage, getImplementationMethod, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, getSystemId, hasLoopingSubexpression, implementsStaticTypeCheck, isUpdatingExpression, iterateEvents, markTailFunctionCalls, process, resetLocalStaticProperties, setContainer, setFiltered, setFlattened, setLocationId, staticTypeCheck, suppressValidation, typeError

Methods inherited from class net.sf.saxon.expr.FunctionCall
addExternalFunctionCallToPathMap, checkArgumentCount, equals, explain, getArguments, getDisplayName, getFunctionName, getNumberOfArguments, hashCode, iterateSubExpressions, promote, replaceSubExpression, setArguments, setFunctionName, simplify, simplifyArguments, toString, typeCheck

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from class net.sf.saxon.functions.SystemFunction
addContextDocumentArgument, addDocToPathMap, checkArguments, computeCardinality, computeSpecialProperties, copy, getDetails, getErrorCodeForTypeErrors, getItemType, getRequiredType, makeSystemFunction, optimize, setDetails, useContextItemAsDefault

- Constructor Detail
  - CompileTimeFunction
```
public CompileTimeFunction()
```
- Method Detail
  - preEvaluate
```
public Expression preEvaluate(ExpressionVisitor visitor)
                       throws XPathException
```
    preEvaluate: this method suppresses compile-time evaluation by doing nothing. (this is because the default implementation of preEvaluate() calls evaluate() which is not available for these functions)
    
    Overrides:
    
    preEvaluate in class FunctionCall
    
    Parameters:
    
    visitor - an expression visitor
    
    Returns:
    
    the result of the early evaluation, or the original expression, or potentially a simplified expression
    
    Throws:
    
    XPathException
  - evaluateItem
```
public final Item evaluateItem(XPathContext c)
                        throws XPathException
```
    Evaluate as a single item
    
    Specified by:
    
    evaluateItem in interface EvaluableItem
    
    Overrides:
    
    evaluateItem in class Expression
    
    Parameters:
    
    c - The context in which the expression is to be evaluated
    
    Returns:
    
    the node or atomic value that results from evaluating the expression; or null to indicate that the result is an empty sequence
    
    Throws:
    
    XPathException - if any dynamic error occurs evaluating the expression
  - iterate
```
public final SequenceIterator iterate(XPathContext c)
```
    Iterate over the results of the function
    
    Specified by:
    
    iterate in interface SequenceIterable
    
    Overrides:
    
    iterate in class Expression
    
    Parameters:
    
    c - supplies the context for evaluation
    
    Returns:
    
    a SequenceIterator that can be used to iterate over the result of the expression

Class CompileTimeFunction

Field Summary

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

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

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

Constructor Summary

Method Summary

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

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

Methods inherited from class java.lang.Object

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

Constructor Detail

CompileTimeFunction

Method Detail

preEvaluate

evaluateItem

iterate