Package net.sf.saxon.expr
Class Assignation
java.lang.Object
net.sf.saxon.expr.ComputedExpression
net.sf.saxon.expr.Assignation
- All Implemented Interfaces:
Serializable
,SourceLocator
,Binding
,Container
,Expression
,InstructionInfoProvider
- Direct Known Subclasses:
ForExpression
,LetExpression
,QuantifiedExpression
Assignation is an abstract superclass for the kinds of expression
that declare range variables: for, some, and every.
- See Also:
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Field Summary
FieldsModifier and TypeFieldDescriptionprotected Expression
protected RangeVariableDeclaration
protected int
protected Expression
protected int
protected String
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
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Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionevaluateVariable
(XPathContext context) Get the value of the range variableprotected Binding[]
extendBindingList
(Binding[] in) Extend an array of variable bindings to include the binding(s) defined in this expressionGet the action expressionint
If this is a local variable held on the local stack frame, return the corresponding slot number.int
Get the number of slots required.Get the "sequence" expression - the one to which the variable is boundGet the variable declarationint
getVariableName
(NamePool pool) Get the display name of the range variable, for diagnostics onlyint
final boolean
Test whether it is permitted to assign to the variable using the saxon:assign extension element.final boolean
isGlobal()
Indicate whether the binding is local or global.Get the immediate subexpressions of this expressionpromote
(PromotionOffer offer) Promote this expression if possibleprotected Expression
promoteWhereClause
(Binding positionBinding) Promote a WHERE clause whose condition doesn't depend on the variable being bound.boolean
replaceSubExpression
(Expression original, Expression replacement) Replace one subexpression by a replacement subexpressionvoid
setAction
(Expression action) Add the "return" or "satisfies" expression, and fix up all references to the range variable that occur within that expressionvoid
setSequence
(Expression sequence) Set the "sequence" expression - the one to which the variable is boundvoid
setSlotNumber
(int nr) Set the slot number for the range variablevoid
Set the reference to the variable declarationsimplify
(StaticContext env) Simplify the expressionvoid
suppressValidation
(int validationMode) Suppress validation on contained element constructors, on the grounds that the parent element is already performing validation.Methods inherited from class net.sf.saxon.expr.ComputedExpression
adoptChildExpression, checkPermittedContents, computeCardinality, computeDependencies, computeSpecialProperties, computeStaticProperties, doPromotion, dynamicError, effectiveBooleanValue, evaluateAsString, evaluateItem, getCardinality, getColumnNumber, getConstructType, getDependencies, getExecutable, getHostLanguage, getImplementationMethod, getInstructionInfo, getIntrinsicDependencies, getLineNumber, getLocationId, getLocationProvider, getParentExpression, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, hasBadParentPointer, iterate, markTailFunctionCalls, process, resetStaticProperties, setLocationId, setParentExpression, setParentExpression, typeError
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Methods inherited from interface net.sf.saxon.expr.Expression
display, getItemType, optimize, typeCheck
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Field Details
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slotNumber
protected int slotNumber -
sequence
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action
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variableName
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nameCode
protected int nameCode -
declaration
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Constructor Details
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Assignation
public Assignation()
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Method Details
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setVariableDeclaration
Set the reference to the variable declaration -
getVariableDeclaration
Get the variable declaration -
setAction
Add the "return" or "satisfies" expression, and fix up all references to the range variable that occur within that expression- Parameters:
action
- the expression that occurs after the "return" keyword of a "for" expression, the "satisfies" keyword of "some/every", or the ":=" operator of a "let" expression.This method must be called after calling setVariableDeclaration()
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isGlobal
public final boolean isGlobal()Indicate whether the binding is local or global. A global binding is one that has a fixed value for the life of a query or transformation; any other binding is local. -
isAssignable
public final boolean isAssignable()Test whether it is permitted to assign to the variable using the saxon:assign extension element. This will only be for an XSLT global variable where the extra attribute saxon:assignable="yes" is present.- Specified by:
isAssignable
in interfaceBinding
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getLocalSlotNumber
public int getLocalSlotNumber()If this is a local variable held on the local stack frame, return the corresponding slot number. In other cases, return -1.- Specified by:
getLocalSlotNumber
in interfaceBinding
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getAction
Get the action expression -
setSequence
Set the "sequence" expression - the one to which the variable is bound -
getSequence
Get the "sequence" expression - the one to which the variable is bound -
setSlotNumber
public void setSlotNumber(int nr) Set the slot number for the range variable -
getRequiredSlots
public int getRequiredSlots()Get the number of slots required. Normally 1, except for a FOR expression with an AT clause, where it is 2. -
simplify
Simplify the expression- Specified by:
simplify
in interfaceExpression
- Overrides:
simplify
in classComputedExpression
- Parameters:
env
- the static context- Returns:
- the simplified expression
- Throws:
XPathException
- if an error is discovered during expression rewriting
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promote
Promote this expression if possible- Specified by:
promote
in interfaceExpression
- Overrides:
promote
in classComputedExpression
- Parameters:
offer
- details of the offer, for example the offer to move expressions that don't depend on the context to an outer level in the containing expression- Returns:
- if the offer is not accepted, return this expression unchanged. Otherwise return the result of rewriting the expression to promote this subexpression
- Throws:
XPathException
- if any error is detected
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suppressValidation
public void suppressValidation(int validationMode) Suppress validation on contained element constructors, on the grounds that the parent element is already performing validation. The default implementation does nothing.- Overrides:
suppressValidation
in classComputedExpression
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extendBindingList
Extend an array of variable bindings to include the binding(s) defined in this expression -
promoteWhereClause
Promote a WHERE clause whose condition doesn't depend on the variable being bound. This rewrites an expression of the formlet $i := SEQ return if (C) then R else ()
to the form:
if (C) then (let $i := SEQ return R) else ()
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iterateSubExpressions
Get the immediate subexpressions of this expression- Specified by:
iterateSubExpressions
in interfaceExpression
- Overrides:
iterateSubExpressions
in classComputedExpression
- Returns:
- an iterator containing the sub-expressions of this expression
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replaceSubExpression
Replace one subexpression by a replacement subexpression- Specified by:
replaceSubExpression
in interfaceContainer
- Overrides:
replaceSubExpression
in classComputedExpression
- Parameters:
original
- the original subexpressionreplacement
- the replacement subexpression- Returns:
- true if the original subexpression is found
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getVariableNameCode
public int getVariableNameCode() -
getVariableFingerprint
public int getVariableFingerprint() -
getVariableName
Get the display name of the range variable, for diagnostics only -
evaluateVariable
Get the value of the range variable- Specified by:
evaluateVariable
in interfaceBinding
- Throws:
XPathException
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