net.sf.saxon.functions
Class TreatFn
java.lang.Object
net.sf.saxon.expr.ComputedExpression
net.sf.saxon.expr.FunctionCall
net.sf.saxon.functions.SystemFunction
net.sf.saxon.functions.TreatFn
- All Implemented Interfaces:
- Expression, Serializable
- public class TreatFn
- extends SystemFunction
This class supports the XPath 2.0 functions exactly-one(), one-or-more(), zero-or-one().
Because Saxon doesn't do strict static type checking, these are essentially identity
functions; the run-time type checking is done as part of the function call mechanism
- See Also:
- Serialized Form
Methods inherited from class net.sf.saxon.functions.SystemFunction |
addContextDocumentArgument, checkArguments, computeCardinality, display, getDetails, getItemType, getName, getRequiredType, main, makeSystemFunction, useContextItemAsDefault |
Methods inherited from class net.sf.saxon.expr.ComputedExpression |
computeDependencies, computeSpecialProperties, computeStaticProperties, dynamicError, effectiveBooleanValue, evaluateAsString, getCardinality, getDependencies, getIntrinsicDependencies, getLineNumber, getSpecialProperties, markTailFunctionCalls, setLineNumber, typeError |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
TreatFn
public TreatFn()
evaluateItem
public Item evaluateItem(XPathContext context)
throws XPathException
- Evaluate the function
- Specified by:
evaluateItem
in interface Expression
- Overrides:
evaluateItem
in class ComputedExpression
- Parameters:
context
- 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 SequenceIterator iterate(XPathContext context)
throws XPathException
- Iterate over the results of the function
- 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