net.sf.saxon.expr
Class EagerLetExpression
java.lang.Object
net.sf.saxon.expr.Expression
net.sf.saxon.expr.Assignation
net.sf.saxon.expr.LetExpression
net.sf.saxon.expr.EagerLetExpression
- All Implemented Interfaces:
- Serializable, SourceLocator, LocationProvider, SaxonLocator, Binding, TailCallReturner, InstructionInfo, Locator
public class EagerLetExpression
- extends LetExpression
An EagerLetExpression is the same as a LetExpression except that the variable is evaluated using
eager evaluation rather than lazy evaluation. This is used when performing diagnostic tracing.
- See Also:
- Serialized Form
Fields inherited from class net.sf.saxon.expr.Expression |
EFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, EVENT_FEED_METHOD, ITEM_FEED_METHOD, ITERATE_METHOD, locationId, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, PROCESS_METHOD, PUSH_SELECTION, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, WATCH_METHOD |
Methods inherited from class net.sf.saxon.expr.LetExpression |
checkPermittedContents, computeCardinality, computeSpecialProperties, copy, effectiveBooleanValue, eval, evaluateItem, evaluatePendingUpdates, explain, getEvaluationMode, getExpressionName, getIntegerBounds, getItemType, implementsStaticTypeCheck, isVacuousExpression, iterate, iterateEvents, markTailFunctionCalls, process, processLeavingTail, promote, setEvaluationMode, setRefCount, staticTypeCheck, toString, typeCheck |
Methods inherited from class net.sf.saxon.expr.Assignation |
addReference, addToPathMap, checkForUpdatingSubexpressions, evaluateVariable, extendBindingList, getAction, getIntegerBoundsForVariable, getLocalSlotNumber, getNominalReferenceCount, getObjectName, getRequiredSlots, getRequiredType, getSequence, getVariableName, getVariableQName, hasVariableBinding, isAssignable, isGlobal, isIndexedVariable, isUpdatingExpression, iterateSubExpressions, promoteWhereClause, refineTypeInformation, replaceSubExpression, replaceVariable, setAction, setIndexedVariable, setRequiredType, setSequence, setSlotNumber, setVariableQName, simplify, suppressValidation |
Methods inherited from class net.sf.saxon.expr.Expression |
adoptChildExpression, computeDependencies, computeStaticProperties, doPromotion, dynamicError, evaluateAsString, explain, getCardinality, getColumnNumber, getColumnNumber, getConstructType, getContainer, getDependencies, getEvaluationMethod, getExecutable, getHostLanguage, getImplementationMethod, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, getSystemId, hasLoopingSubexpression, isSubtreeExpression, iterateSameFocusSubExpressions, resetLocalStaticProperties, setContainer, setEvaluationMethod, setFiltered, setFlattened, setLocationId, typeError |
EagerLetExpression
public EagerLetExpression()
optimize
public Expression optimize(ExpressionVisitor visitor,
ExpressionVisitor.ContextItemType contextItemType)
throws XPathException
- Description copied from class:
LetExpression
- Perform optimisation of an expression and its subexpressions.
This method is called after all references to functions and variables have been resolved
to the declaration of the function or variable, and after all type checking has been done.
- Overrides:
optimize
in class LetExpression
- Parameters:
visitor
- an expression visitorcontextItemType
- the static type of "." at the point where this expression is invoked.
The parameter is set to null if it is known statically that the context item will be undefined.
If the type of the context item is not known statically, the argument is set to
Type.ITEM_TYPE
- Returns:
- the original expression, rewritten if appropriate to optimize execution
- Throws:
XPathException
- if an error is discovered during this phase
(typically a type error)
Copyright (c) 2004-2011 Saxonica Limited. All rights reserved.