- All Implemented Interfaces:
public class Assign extends Instruction implements BindingReferenceCompiled instruction deriving from saxon:assign element in stylesheet.
The saxon:assign element has mandatory attribute name and optional attribute expr. It also allows xsl:extension-element-prefixes etc.
All Methods Instance Methods Concrete Methods Modifier and Type Method Description
copy(RebindingMap rebindings)Copy an expression.
export(ExpressionPresenter out)Diagnostic print of expression structure.
fixup(Binding binding)Fix up this binding reference to a binding
getInstructionNameCode()Get the name of this instruction for diagnostic and tracing purposes
getIntrinsicDependencies()Determine the intrinsic dependencies of an expression, that is, those which are not derived from the dependencies of its subexpressions.
operands()Get the immediate sub-expressions of this expression, with information about the relationship of each expression to its parent expression.
processLeavingTail(Outputter output, XPathContext context)ProcessLeavingTail: called to do the real work of this instruction.
setStaticType(SequenceType type, GroundedValue constantValue, int properties)Fix up the static type of this variable reference; optionally, supply a constant value for the variable.
typeCheck(ExpressionVisitor visitor, ContextItemStaticInfo contextInfo)Perform type checking of an expression and its subexpressions.
Methods inherited from class net.sf.saxon.expr.instruct.Instruction
alwaysCreatesNewNodes, assembleParams, assembleTunnelParams, computeCardinality, computeSpecialProperties, dynamicError, evaluateAsString, evaluateItem, getExpressionName, getImplementationMethod, getItemType, getNetCost, getSourceLocator, isInstruction, isXSLT, iterate, mayCreateNewNodes, process, someOperandCreatesNewNodes
Methods inherited from class net.sf.saxon.expr.Expression
addToPathMap, adoptChildExpression, allowExtractingCommonSubexpressions, checkedOperands, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeHashCode, computeStaticProperties, dynamicError, effectiveBooleanValue, equals, evaluatePendingUpdates, explain, getCardinality, getConfiguration, getCost, getDependencies, getEvaluationMethod, getExtraProperty, getIntegerBounds, getInterpretedExpression, getLocalRetainedStaticContext, getLocation, getObjectName, getPackageData, getParentExpression, getProperties, getProperty, getRetainedStaticContext, getScopingExpression, getSlotsUsed, getSpecialProperties, getStaticBaseURI, getStaticBaseURIString, getStaticType, getStaticUType, getStreamerName, getTracingTag, hasCompatibleStaticContext, hashCode, hasSpecialProperty, hasVariableBinding, identityHashCode, implementsStaticTypeCheck, isCallOn, isEqual, isIdentical, isLiftable, isMultiThreaded, isStaticPropertiesKnown, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, markTailFunctionCalls, operandList, operandSparseList, optimize, optimizeChildren, prepareForStreaming, resetLocalStaticProperties, restoreParentPointers, setEvaluationMethod, setExtraProperty, setFiltered, setFlattened, setLocation, setParentExpression, setRetainedStaticContext, setRetainedStaticContextLocally, setRetainedStaticContextThoroughly, setStaticProperty, simplify, simplifyChildren, staticTypeCheck, suppressValidation, toPattern, toShortString, toString, typeCheckChildren, typeError, unordered, verifyParentPointers
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
public Assign(Expression select)
public void setStaticType(SequenceType type, GroundedValue constantValue, int properties)Description copied from interface:
BindingReferenceFix up the static type of this variable reference; optionally, supply a constant value for the variable. Also supplies other static properties of the expression to which the variable is bound, for example whether it is an ordered node-set.
- Specified by:
type- The static type of the variable reference, typically either the declared type of the variable, or the static type of the expression to which the variable is bound
constantValue- if non-null, indicates that the value of the variable is known at compile time, and supplies the value
properties- static properties of the expression to which the variable is bound
public void setSelectExpr(Expression select)
public Expression getSelectExpr()
public java.lang.Iterable<Operand> operands()Get the immediate sub-expressions of this expression, with information about the relationship of each expression to its parent expression. Default implementation works off the results of iterateSubExpressions()
If the expression is a Callable, then it is required that the order of the operands returned by this function is the same as the order of arguments supplied to the corresponding call() method.
public void fixup(Binding binding)Description copied from interface:
BindingReferenceFix up this binding reference to a binding
public Expression typeCheck(ExpressionVisitor visitor, ContextItemStaticInfo contextInfo) throws XPathExceptionPerform type checking of an expression and its subexpressions. This is the second phase of static optimization.
This checks statically that the operands of the expression have the correct type; if necessary it generates code to do run-time type checking or type conversion. A static type error is reported only if execution cannot possibly succeed, that is, if a run-time type error is inevitable. The call may return a modified form of the expression.
This method is called after all references to functions and variables have been resolved to the declaration of the function or variable. However, the types of such functions and variables may not be accurately known if they have not been explicitly declared.
visitor- an expression visitor
contextInfo- Information available statically about the context item: whether it is (possibly) absent; its static type; its streaming posture.
- the original expression, rewritten to perform necessary run-time type checks, and to perform other type-related optimizations
XPathException- if an error is discovered during this phase (typically a type error)
public int getIntrinsicDependencies()Determine the intrinsic dependencies of an expression, that is, those which are not derived from the dependencies of its subexpressions. For example, position() has an intrinsic dependency on the context position, while (position()+1) does not. The default implementation of the method returns 0, indicating "no dependencies".
public Expression copy(RebindingMap rebindings)Copy an expression. This makes a deep copy.
public int getInstructionNameCode()Get the name of this instruction for diagnostic and tracing purposes
public TailCall processLeavingTail(Outputter output, XPathContext context) throws XPathExceptionDescription copied from class:
InstructionProcessLeavingTail: called to do the real work of this instruction. This method must be implemented in each subclass. The results of the instruction are written to the current Receiver, which can be obtained via the Controller.
- Specified by:
- Specified by:
output- the destination for the result
context- The dynamic context of the transformation, giving access to the current node, the current variables, etc.
- null if the instruction has completed execution; or a TailCall indicating a function call or template call that is delegated to the caller, to be made after the stack has been unwound so as to save stack space.
XPathException- if a dynamic error occurs during the evaluation of the instruction
public void export(ExpressionPresenter out) throws XPathExceptionDiagnostic print of expression structure. The abstract expression tree is written to the supplied output destination.