## net.sf.saxon.style
Class StyleElement

    java.lang.Object
      net.sf.saxon.tree.linked.NodeImpl
          net.sf.saxon.tree.linked.ElementImpl
              net.sf.saxon.style.StyleElement

All Implemented Interfaces:
  Serializable, Source, SourceLocator, LocationProvider, SaxonLocator, PullEvent, Container, FingerprintedNode, Item, MutableNodeInfo, NamespaceResolver, NodeInfo, ValueRepresentation, InstructionInfo, SiblingCountingNode, Locator

Direct Known Subclasses:
  AbsentExtensionElement, ExtensionInstruction, LiteralResultElement, SaxonCollation, SaxonDoctype, SaxonEntityRef, SaxonImportQuery, SaxonWhile, SQLColumn, XSLAnalyzeString, XSLApplyImports, XSLApplyTemplates, XSLAttributeSet, XSLBreakOrContinue, XSLCallTemplate, XSLCatch, XSLCharacterMap, XSLChoose, XSLCopy, XSLCopyOf, XSLDecimalFormat, XSLDocument, XSLElement, XSLEvaluate, XSLFallback, XSLForEach, XSLForEachGroup, XSLFork, XSLFunction, XSLGeneralIncorporate, XSLGeneralVariable, XSLIf, XSLImportSchema, XSLIterate, XSLKey, XSLLeafNodeConstructor, XSLMatchingSubstring, XSLMessage, XSLMode, XSLNamespaceAlias, XSLNextMatch, XSLNumber, XSLOnCompletion, XSLOtherwise, XSLOutput, XSLOutputCharacter, XSLPerformSort, XSLPreserveSpace, XSLResultDocument, XSLSequence, XSLSort, XSLStylesheet, XSLTemplate, XSLTry, XSLWhen

    public abstract class StyleElement

extends ElementImpl
implements Locator, Container, InstructionInfo

Abstract superclass for all element nodes in the stylesheet.

Note: this class implements Locator. The element retains information about its own location in the stylesheet, which is useful when an XSLT static error is found.

See Also:
  Serialized Form

Field Summary
`static int` `ACTION_COMPILE`
`static int` `ACTION_FIXUP`
`static int` `ACTION_OPTIMIZE`
`static int` `ACTION_PROCESS_ATTRIBUTES`
`static int` `ACTION_TYPECHECK`
`static int` `ACTION_VALIDATE`
`protected int` `actionsCompleted`
`protected String` `defaultCollationName`
`protected String` `defaultXPathNamespace`
`protected short[]` `extensionNamespaces`
`static int` `REPORT_ALWAYS`
`static int` `REPORT_IF_INSTANTIATED`
`static int` `REPORT_UNLESS_FALLBACK_AVAILABLE`
`static int` `REPORT_UNLESS_FORWARDS_COMPATIBLE`
`protected int` `reportingCircumstances`
`protected StaticContext` `staticContext`
`protected XPathException` `validationError`
`protected DecimalValue` `version`

Fields inherited from class net.sf.saxon.tree.linked.NodeImpl
`NODE_LETTER`

Fields inherited from interface net.sf.saxon.om.NodeInfo
`ALL_NAMESPACES, EMPTY_NAMESPACE_LIST, IS_DTD_TYPE, IS_NILLED, LOCAL_NAMESPACES, NO_NAMESPACES`

Constructor Summary
`StyleElement()` Constructor

Method Summary
`protected void` `addChild(NodeImpl node, int index)` Add a child node to this node.
`protected int` `allocateLocationId(String systemId, int lineNumber)` Allocate a location identifier
`void` `allocatePatternSlots(int slots)` Allocate space for range variables within predicates in the match pattern.
`void` `allocateSlots(Expression exp)` Allocate slots in the local stack frame to range variables used in an XPath expression
`XSLVariableDeclaration` `bindVariable(StructuredQName qName)` Bind a variable used in this element to the compiled form of the XSLVariable element in which it is declared
`void` `checkEmpty()` Convenience method to check that the stylesheet element is empty
`protected void` `checkSortComesFirst(boolean sortRequired)` Check that among the children of this element, any xsl:sort elements precede any other elements
`void` `checkTopLevel(String errorCode)` Convenience method to check that the stylesheet element is at the top level
`protected void` `checkUnknownAttribute(int nc)` Check whether an unknown attribute is permitted.
`void` `compact(int size)` Compact the space used by this node
`abstract Expression` `compile(Executable exec, Declaration decl)` Compile the instruction on the stylesheet tree into an executable instruction for use at run-time.
`protected void` `compileError(String message)` Report a static error in the stylesheet
`protected void` `compileError(String message, String errorCode)` Compile time error, specifying an error code
`protected void` `compileError(String message, StructuredQName errorCode)` Compile time error, specifying an error code
`protected void` `compileError(XPathException error)` Report an error with diagnostic information
`Expression` `compileSequenceConstructor(Executable exec, Declaration decl, SequenceIterator iter, boolean includeParams)` Compile the children of this instruction on the stylesheet tree, adding the subordinate instructions to the parent instruction on the execution tree.
`protected void` `compileWarning(String message, String errorCode)`
`protected void` `compileWarning(String message, StructuredQName errorCode)`
`protected boolean` `definesExcludedNamespace(short uriCode)` Check whether this node excludes a particular namespace from the result.
`protected boolean` `definesExtensionElement(short uriCode)` Check whether a particular extension element namespace is defined on this node.
`protected AxisIterator` `enumerateChildren(NodeTest test)` Get an enumeration of the children of this node
`protected Expression` `fallbackProcessing(Executable exec, Declaration decl, StyleElement instruction)` Perform fallback processing.
`void` `fixupReferences()` Fix up references from XPath expressions.
`boolean` `forwardsCompatibleModeIsEnabled()` Determine whether forwards-compatible mode is enabled for this element
`protected AttributeSet[]` `getAttributeSets(String use, List<Declaration> list)` Get the list of attribute-sets associated with this element.
`String` `getAttributeValue(String clarkName)` Get an attribute value given the Clark name of the attribute (that is, the name in {uri}local format).
`int` `getColumnNumber(long locationId)` Get the column number within the document, entity, or module containing a particular location
`protected ItemType` `getCommonChildItemType()` Get the most general type of item returned by the children of this instruction
`int` `getConstructType()` Get the type of construct.
`int` `getContainerGranularity()` Get the granularity of the container.
`SlotManager` `getContainingSlotManager()` Get the SlotManager for the containing Procedure definition
`XSLStylesheet` `getContainingStylesheet()` Get the containing XSLStylesheet element
`protected String` `getDefaultCollationName()` Get the default collation for this stylesheet element.
`protected String` `getDefaultXPathNamespace()` Get the default XPath namespace for elements and types
`DecimalValue` `getEffectiveVersion()` Get the numeric value of the version number appearing as an attribute on this element, or inherited from its ancestors
`Executable` `getExecutable()` Get the Executable (representing a complete stylesheet or query) of which this Container forms part
`NodeInfo` `getFirstChild()` Get the first child node of the element
`int` `getHostLanguage()` Get the host language (XSLT, XQuery, XPath) used to implement the code in this container
`NodeInfo` `getLastChild()` Get the last child node of the element
`protected StyleElement` `getLastChildInstruction()` Find the last child instruction of this instruction.
`int` `getLineNumber(long locationId)` Get the line number within the document, entity or module containing a particular location
`LocationProvider` `getLocationProvider()` Get the LocationProvider allowing location identifiers to be resolved.
`NamespaceResolver` `getNamespaceResolver()` Get the namespace context of the instruction.
`protected NodeImpl` `getNthChild(int n)` Get the nth child node of the element (numbering from 0)
`int` `getNumberOfChildren()` Determine how many children the node has
`StructuredQName` `getObjectName()` Get a name identifying the object of the expression, for example a function name, template name, variable name, key name, element name, etc.
`PreparedStylesheet` `getPreparedStylesheet()` Get the PreparedStylesheet object.
`PrincipalStylesheetModule` `getPrincipalStylesheetModule()` Get the principal stylesheet module
`DecimalValue` `getProcessorVersion()` Determine what version of the XSLT the configured processor supports
`Iterator` `getProperties()` Get an iterator over all the properties available.
`Object` `getProperty(String name)` Get the value of a particular property of the instruction.
`protected int` `getRawSequenceNumber()`
`protected ItemType` `getReturnedItemType()` Determine the type of item returned by this instruction (only relevant if it is an instruction).
`SchemaType` `getSchemaType(String typeAtt)` Get the Schema type definition for a type named in the stylesheet (in a "type" attribute).
`protected long` `getSequenceNumber()` Get the node sequence number (in document order).
`StaticContext` `getStaticContext()` Get the static context for expressions on this element
`String` `getStringValue()` Return the string-value of the node, that is, the concatenation of the character content of all descendent elements and text nodes.
`CharSequence` `getStringValueCS()` Get the value of the item as a CharSequence.
`String` `getSystemId(long locationId)` Get the URI of the document, entity, or module containing a particular location
`int` `getTypeAnnotation(SchemaType schemaType)` Get the type annotation to use for a given schema type
`protected WithParam[]` `getWithParamInstructions(Executable exec, Declaration decl, boolean tunnel, Expression caller)` Get the list of xsl:with-param elements for a calling element (apply-templates, call-template, apply-imports, next-match).
`boolean` `hasChildNodes()` Determine if the node has any children.
`protected void` `index(Declaration decl, PrincipalStylesheetModule top)` Method supplied by declaration elements to add themselves to a stylesheet-level index
`void` `insertChildren(NodeInfo[] source, boolean atStart, boolean inherit)` Insert a sequence of nodes as children of this node.
`protected void` `insertChildrenAt(NodeInfo[] source, int index, boolean inherit)` Insert children before or after a given existing child
`boolean` `isActionCompleted(int action)` Ask if an action on this StyleElement has been completed
`boolean` `isDeclaration()` Ask whether this node is a declaration, that is, a permitted child of xsl:stylesheet (including xsl:include and xsl:import).
`boolean` `isExcludedNamespace(short uriCode)` Check whether a namespace uri defines an namespace excluded from the result.
`protected boolean` `isExplaining()` Determine whether saxon:explain has been set to "yes"
`boolean` `isExtensionNamespace(short uriCode)` Check whether a namespace uri defines an extension element.
`boolean` `isInstruction()` Ask whether this node is an instruction.
`protected boolean` `isPermittedChild(StyleElement child)` Check whether a given child is permitted for this element.
`protected void` `issueWarning(String message, SourceLocator locator)` Report a warning to the error listener
`protected void` `issueWarning(TransformerException error)` Report a warning to the error listener
`boolean` `isTopLevel()` Test whether this is a top-level element
`boolean` `isXslt30Processor()` Ask whether the configured XSLT processor supports XSLT 3.0
`protected Expression` `makeAttributeValueTemplate(String expression)` Make an attribute value template in the context of this stylesheet element
`Expression` `makeExpression(String expression)` Compile an XPath expression in the context of this stylesheet element
`ExpressionVisitor` `makeExpressionVisitor()` Make an expression visitor
`SavedNamespaceContext` `makeNamespaceContext()` Make a NamespaceContext object representing the list of in-scope namespaces.
`Pattern` `makePattern(String pattern)` Make a pattern in the context of this stylesheet element
`StructuredQName` `makeQName(String lexicalQName)` Make a structured QName, using this Element as the context for namespace resolution, and registering the code in the namepool.
`SequenceType` `makeSequenceType(String sequenceType)` Process an attribute whose value is a SequenceType
`protected SortKeyDefinition[]` `makeSortKeys(Declaration decl)` Construct sort keys for a SortedIterator
`protected static TraceWrapper` `makeTraceInstruction(StyleElement source, Expression child)` Create a trace instruction to wrap a real instruction
`protected boolean` `markTailCalls()` Mark tail-recursive calls on templates and functions.
`protected boolean` `mayContainFallback()` Determine whether this type of element is allowed to contain an xsl:fallback instruction.
`protected boolean` `mayContainParam(String attName)` Determine whether this type of element is allowed to contain an xsl:param element
`protected boolean` `mayContainSequenceConstructor()` Determine whether this type of element is allowed to contain a sequence constructor
`void` `postValidate()` Hook to allow additional validation of a parent element immediately after its children have been validated.
`protected abstract void` `prepareAttributes()` Set the attribute list for the element.
`protected void` `processAllAttributes()` Process the attributes of this element and all its children
`protected void` `processAttributes()` Process the attribute list for the element.
`protected void` `processDefaultCollationAttribute(String ns)` Process the [xsl:]default-xpath-namespace attribute if there is one
`protected void` `processDefaultXPathNamespaceAttribute(String ns)` Process the [xsl:]xpath-default-namespace attribute if there is one
`protected void` `processExcludedNamespaces(String ns)` Process the [xsl:]exclude-result-prefixes attribute if there is one
`protected void` `processExtensionElementAttribute(String ns)` Process the [xsl:]extension-element-prefixes attribute if there is one
`void` `processStandardAttributes(String namespace)` Process the standard attributes such as [xsl:]default-collation
`protected void` `processVersionAttribute(String ns)` Process the [xsl:]version attribute if there is one
`protected void` `removeChild(NodeImpl child)` Remove a given child
`protected void` `replaceChildrenAt(NodeInfo[] source, int index, boolean inherit)` Replace child at a given index by new children
`void` `reportAbsence(String attribute)` Convenience method to report the absence of a mandatory attribute
`protected boolean` `seesAvuncularVariables()` Ask whether variables declared in an "uncle" element are visible.
`void` `setActionCompleted(int action)` Say that an action on this StyleElement has been completed
`protected void` `setChildren(Object children)` Set the children of this node
`void` `setObjectName(StructuredQName qName)` Set the object name, for example the name of a function, variable, or template declared on this element
`protected void` `setRawSequenceNumber(int seq)`
`void` `setValidationError(TransformerException reason, int circumstances)` Set a validation error.
`void` `substituteFor(StyleElement temp)` Make this node a substitute for a temporary one previously added to the tree.
`Expression` `typeCheck(String name, Expression exp)` Type-check an expression.
`Pattern` `typeCheck(String name, Pattern pattern)` Type-check a pattern.
`protected void` `undeclaredNamespaceError(String prefix, String errorCode)`
`void` `validate(Declaration decl)` Check that the stylesheet element is valid.
`protected void` `validateChildren(Declaration decl)` Validate the children of this node, recursively.
`void` `validateSubtree(Declaration decl)` Recursive walk through the stylesheet to validate all nodes
`boolean` `xPath10ModeIsEnabled()` Determine whether 1.0-compatible mode is enabled for this element

Methods inherited from class net.sf.saxon.tree.linked.ElementImpl

`addAttribute, addNamespace, copy, delete, fixupInsertedNamespaces, generateId, getAttributeList, getAttributeValue, getAttributeValue, getBaseURI, getColumnNumber, getDeclaredNamespaces, getDocumentRoot, getInScopeNamespaceCodes, getLineNumber, getNameCode, getNamespaceList, getNodeKind, getPrefixForURI, getRoot, getSystemId, getTypeAnnotation, getURICodeForPrefix, getURICodeForPrefixCode, getURIForPrefix, gsetAttributeCollection, initialise, isId, isNilled, iteratePrefixes, removeAttribute, removeTypeAnnotation, rename, replaceStringValue, setAttributeList, setLineAndColumn, setLocation, setNameCode, setNamespaceDeclarations, setNamespaceList, setSystemId, setTypeAnnotation`

Methods inherited from class net.sf.saxon.tree.linked.NodeImpl

`atomize, compareOrder, equals, getConfiguration, getDisplayName, getDocumentNumber, getFingerprint, getLocalPart, getNamePool, getNextInDocument, getNextSibling, getParent, getPhysicalRoot, getPrefix, getPreviousInDocument, getPreviousSibling, getPublicId, getRawParent, getSiblingPosition, getTypedValue, getURI, insertSiblings, isDeleted, isIdref, isSameNodeInfo, iterateAxis, iterateAxis, newBuilder, replace, setRawParent, setSiblingPosition`

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

Methods inherited from interface net.sf.saxon.trace.InstructionInfo
`getLineNumber, getSystemId`

Methods inherited from interface org.xml.sax.Locator
`getColumnNumber, getPublicId`

Methods inherited from interface javax.xml.transform.SourceLocator
`getColumnNumber, getPublicId`

Methods inherited from interface net.sf.saxon.om.NodeInfo
`hashCode`

Field Detail

### extensionNamespaces

    protected short[] extensionNamespaces

### version

    protected DecimalValue version

### staticContext

    protected StaticContext staticContext

### validationError

    protected XPathException validationError

### reportingCircumstances

    protected int reportingCircumstances

### defaultXPathNamespace

    protected String defaultXPathNamespace

### defaultCollationName

    protected String defaultCollationName

### REPORT_ALWAYS

    public static final int REPORT_ALWAYS

See Also:
  Constant Field Values

### REPORT_UNLESS_FORWARDS_COMPATIBLE

    public static final int REPORT_UNLESS_FORWARDS_COMPATIBLE

See Also:
  Constant Field Values

### REPORT_IF_INSTANTIATED

    public static final int REPORT_IF_INSTANTIATED

See Also:
  Constant Field Values

### REPORT_UNLESS_FALLBACK_AVAILABLE

    public static final int REPORT_UNLESS_FALLBACK_AVAILABLE

See Also:
  Constant Field Values

### actionsCompleted

    protected int actionsCompleted

### ACTION_VALIDATE

    public static final int ACTION_VALIDATE

See Also:
  Constant Field Values

### ACTION_COMPILE

    public static final int ACTION_COMPILE

See Also:
  Constant Field Values

### ACTION_TYPECHECK

    public static final int ACTION_TYPECHECK

See Also:
  Constant Field Values

### ACTION_OPTIMIZE

    public static final int ACTION_OPTIMIZE

See Also:
  Constant Field Values

### ACTION_FIXUP

    public static final int ACTION_FIXUP

See Also:
  Constant Field Values

### ACTION_PROCESS_ATTRIBUTES

    public static final int ACTION_PROCESS_ATTRIBUTES

See Also:
  Constant Field Values

Constructor Detail

### StyleElement

    public StyleElement()

  Constructor

Method Detail

### getExecutable

    public Executable getExecutable()

  Description copied from interface: `Container`
  Get the Executable (representing a complete stylesheet or query) of which this Container forms part

  Specified by:
    `getExecutable` in interface `Container`
  Returns:
    the executable

### getLocationProvider

    public LocationProvider getLocationProvider()

  Get the LocationProvider allowing location identifiers to be resolved.

  Specified by:
    `getLocationProvider` in interface `Container`
  Returns:
    the location provider

### getStaticContext

    public StaticContext getStaticContext()

  Get the static context for expressions on this element

  Returns:
    the static context

### getContainerGranularity

    public int getContainerGranularity()

  Get the granularity of the container.

  Specified by:
    `getContainerGranularity` in interface `Container`
  Returns:
    0 for a temporary container created during parsing; 1 for a container that operates at the level of an XPath expression; 2 for a container at the level of a global function or template

### makeExpressionVisitor

    public ExpressionVisitor makeExpressionVisitor()

  Make an expression visitor

  Returns:
    the expression visitor

### isExplaining

    protected boolean isExplaining()

  Determine whether saxon:explain has been set to "yes"

  Returns:
    true if saxon:explain has been set to "yes" on this element

### substituteFor

    public void substituteFor(StyleElement temp)

  Make this node a substitute for a temporary one previously added to the tree. See StyleNodeFactory for details. "A node like the other one in all things but its class". Note that at this stage, the node will not yet be known to its parent, though it will contain a reference to its parent; and it will have no children.

  Parameters:
    `temp` - the element which this one is substituting for

### setValidationError

    public void setValidationError(TransformerException reason,
                                   int circumstances)

  Set a validation error. This is an error detected during construction of this element on the stylesheet, but which is not to be reported until later.

  Parameters:
    `reason` - the details of the error
    `circumstances` - a code identifying the circumstances under which the error is to be reported

### isInstruction

    public boolean isInstruction()

  Ask whether this node is an instruction. The default implementation says it isn't.

  Returns:
    true if this element is an instruction

### isDeclaration

    public boolean isDeclaration()

  Ask whether this node is a declaration, that is, a permitted child of xsl:stylesheet (including xsl:include and xsl:import). The default implementation returns false

  Returns:
    true if the element is a permitted child of xsl:stylesheet or xsl:transform

### getReturnedItemType

    protected ItemType getReturnedItemType()

  Determine the type of item returned by this instruction (only relevant if it is an instruction). Default implementation returns Type.ITEM, indicating that we don't know, it might be anything. Returns null in the case of an element such as xsl:sort or xsl:variable that can appear in a sequence constructor but contributes nothing to the result sequence.

  Returns:
    the item type returned

### getCommonChildItemType

    protected ItemType getCommonChildItemType()

  Get the most general type of item returned by the children of this instruction

  Returns:
    the lowest common supertype of the item types returned by the children

### markTailCalls

    protected boolean markTailCalls()

  Mark tail-recursive calls on templates and functions. For most instructions, this returns false.

  Returns:
    true if one or more tail calls were identified

### mayContainSequenceConstructor

    protected boolean mayContainSequenceConstructor()

  Determine whether this type of element is allowed to contain a sequence constructor

  Returns:
    true if this instruction is allowed to contain a sequence constructor

### mayContainFallback

    protected boolean mayContainFallback()

  Determine whether this type of element is allowed to contain an xsl:fallback instruction. Note that this is only relevant if the element is an instruction.

  Returns:
    true if this element is allowed to contain an xsl:fallback

### mayContainParam

    protected boolean mayContainParam(String attName)

  Determine whether this type of element is allowed to contain an xsl:param element

  Parameters:
    `attName` - if null, the method tests whether an xsl:param child is allowed. If non-null, it tests whether an xsl:param child with the given attribute name is allowed
  Returns:
    true if this element is allowed to contain an xsl:param

### getContainingStylesheet

    public XSLStylesheet getContainingStylesheet()

  Get the containing XSLStylesheet element

  Returns:
    the XSLStylesheet element representing the outermost element of the containing stylesheet module. Exceptionally, return null if there is no containing XSLStylesheet element

### makeQName

    public final StructuredQName makeQName(String lexicalQName)
                                    throws XPathException,
                                           NamespaceException

  Make a structured QName, using this Element as the context for namespace resolution, and registering the code in the namepool. If the name is unprefixed, the default namespace is not used.

  Parameters:
    `lexicalQName` - The lexical QName as written, in the form "[prefix:]localname". The name must have already been validated as a syntactically-correct QName. Leading and trailing whitespace will be trimmed
  Returns:
    the StructuredQName representation of this lexical QName
  Throws:
    `XPathException` - if the qname is not a lexically-valid QName, or if the name is in a reserved namespace.
    `NamespaceException` - if the prefix of the qname has not been declared

### makeNamespaceContext

    public SavedNamespaceContext makeNamespaceContext()

  Make a NamespaceContext object representing the list of in-scope namespaces. This will be a copy of the namespace context with no references to objects in the stylesheet tree, so that it can be kept until run-time without locking the tree down in memory.

  Returns:
    a copy of the namespace context

### getNamespaceResolver

    public NamespaceResolver getNamespaceResolver()

  Get the namespace context of the instruction.

  Returns:
    the namespace context. This method does not make a copy of the namespace context, so a reference to the returned NamespaceResolver will lock the stylesheet tree in memory.

### processAllAttributes

    protected void processAllAttributes()
                                 throws XPathException

  Process the attributes of this element and all its children

  Throws:
    `XPathException` - in the event of a static error being detected

### processStandardAttributes

    public void processStandardAttributes(String namespace)
                                   throws XPathException

  Process the standard attributes such as [xsl:]default-collation

  Parameters:
    `namespace` - either "" to find the attributes in the null namespace, or NamespaceConstant.XSLT to find them in the XSLT namespace
  Throws:
    `XPathException`

### getAttributeValue

    public String getAttributeValue(String clarkName)

  Get an attribute value given the Clark name of the attribute (that is, the name in {uri}local format).

  Parameters:
    `clarkName` - the name of the attribute in {uri}local format
  Returns:
    the value of the attribute if it exists, or null otherwise

### processAttributes

    protected final void processAttributes()
                                    throws XPathException

  Process the attribute list for the element. This is a wrapper method that calls prepareAttributes (provided in the subclass) and traps any exceptions

  Throws:
    `XPathException`

### checkUnknownAttribute

    protected void checkUnknownAttribute(int nc)
                                  throws XPathException

  Check whether an unknown attribute is permitted.

  Parameters:
    `nc` - The name code of the attribute name
  Throws:
    `XPathException` - (and reports the error) if this is an attribute that is not permitted on the containing element

### prepareAttributes

    protected abstract void prepareAttributes()
                                       throws XPathException

  Set the attribute list for the element. This is called to process the attributes (note the distinction from processAttributes in the superclass). Must be supplied in a subclass

  Throws:
    `XPathException`

### getLastChildInstruction

    protected StyleElement getLastChildInstruction()

  Find the last child instruction of this instruction. Returns null if there are no child instructions, or if the last child is a text node.

  Returns:
    the last child instruction, or null if there are no child instructions

### makeExpression

    public Expression makeExpression(String expression)
                              throws XPathException

  Compile an XPath expression in the context of this stylesheet element

  Parameters:
    `expression` - the source text of the XPath expression
  Returns:
    the compiled expression tree for the XPath expression
  Throws:
    `XPathException`

### makePattern

    public Pattern makePattern(String pattern)
                        throws XPathException

  Make a pattern in the context of this stylesheet element

  Parameters:
    `pattern` - the source text of the pattern
  Returns:
    the compiled pattern
  Throws:
    `XPathException`

### makeAttributeValueTemplate

    protected Expression makeAttributeValueTemplate(String expression)
                                             throws XPathException

  Make an attribute value template in the context of this stylesheet element

  Parameters:
    `expression` - the source text of the attribute value template
  Returns:
    a compiled XPath expression that computes the value of the attribute (including concatenating the results of embedded expressions with any surrounding fixed text)
  Throws:
    `XPathException`

### makeSequenceType

    public SequenceType makeSequenceType(String sequenceType)
                                  throws XPathException

  Process an attribute whose value is a SequenceType

  Parameters:
    `sequenceType` - the source text of the attribute
  Returns:
    the processed sequence type
  Throws:
    `XPathException` - if the syntax is invalid or for example if it refers to a type that is not in the static context

### processExtensionElementAttribute

    protected void processExtensionElementAttribute(String ns)
                                             throws XPathException

  Process the [xsl:]extension-element-prefixes attribute if there is one

  Parameters:
    `ns` - the namespace URI of the attribute - either the XSLT namespace or "" for the null namespace
  Throws:
    `XPathException`

### processExcludedNamespaces

    protected void processExcludedNamespaces(String ns)
                                      throws XPathException

  Process the [xsl:]exclude-result-prefixes attribute if there is one

  Parameters:
    `ns` - the namespace URI of the attribute required, either the XSLT namespace or ""
  Throws:
    `XPathException`

### processVersionAttribute

    protected void processVersionAttribute(String ns)
                                    throws XPathException

  Process the [xsl:]version attribute if there is one

  Parameters:
    `ns` - the namespace URI of the attribute required, either the XSLT namespace or ""
  Throws:
    `XPathException`

### getEffectiveVersion

    public DecimalValue getEffectiveVersion()

  Get the numeric value of the version number appearing as an attribute on this element, or inherited from its ancestors

  Returns:
    the version number as a decimal

### forwardsCompatibleModeIsEnabled

    public boolean forwardsCompatibleModeIsEnabled()

  Determine whether forwards-compatible mode is enabled for this element

  Returns:
    true if forwards-compatible mode is enabled

### xPath10ModeIsEnabled

    public boolean xPath10ModeIsEnabled()

  Determine whether 1.0-compatible mode is enabled for this element

  Returns:
    true if 1.0 compatable mode is enabled, that is, if this or an enclosing element specifies an [xsl:]version attribute whose value is less than 2.0

### getProcessorVersion

    public DecimalValue getProcessorVersion()

  Determine what version of the XSLT the configured processor supports

  Returns:
    the version of XSLT supported by the processor

### isXslt30Processor

    public boolean isXslt30Processor()

  Ask whether the configured XSLT processor supports XSLT 3.0

  Returns:
    true if the configured XSLT processor supports XSLT 3.0

### processDefaultCollationAttribute

    protected void processDefaultCollationAttribute(String ns)
                                             throws XPathException

  Process the [xsl:]default-xpath-namespace attribute if there is one

  Parameters:
    `ns` - the namespace of the attribute required, either the XSLT namespace or ""
  Throws:
    `XPathException`

### getDefaultCollationName

    protected String getDefaultCollationName()

  Get the default collation for this stylesheet element. If no default collation is specified in the stylesheet, return the Unicode codepoint collation name.

  Returns:
    the name of the default collation

### definesExtensionElement

    protected boolean definesExtensionElement(short uriCode)

  Check whether a particular extension element namespace is defined on this node. This checks this node only, not the ancestor nodes. The implementation checks whether the prefix is included in the [xsl:]extension-element-prefixes attribute.

  Parameters:
    `uriCode` - the namespace URI code being tested
  Returns:
    true if this namespace is defined on this element as an extension element namespace

### isExtensionNamespace

    public boolean isExtensionNamespace(short uriCode)

  Check whether a namespace uri defines an extension element. This checks whether the namespace is defined as an extension namespace on this or any ancestor node.

  Parameters:
    `uriCode` - the namespace URI code being tested
  Returns:
    true if the URI is an extension element namespace URI

### definesExcludedNamespace

    protected boolean definesExcludedNamespace(short uriCode)

  Check whether this node excludes a particular namespace from the result. This method checks this node only, not the ancestor nodes.

  Parameters:
    `uriCode` - the code of the namespace URI being tested
  Returns:
    true if the namespace is excluded by virtue of an [xsl:]exclude-result-prefixes attribute

### isExcludedNamespace

    public boolean isExcludedNamespace(short uriCode)

  Check whether a namespace uri defines an namespace excluded from the result. This checks whether the namespace is defined as an excluded namespace on this or any ancestor node.

  Parameters:
    `uriCode` - the code of the namespace URI being tested
  Returns:
    true if this namespace URI is a namespace excluded by virtue of exclude-result-prefixes on this element or on an ancestor element

### processDefaultXPathNamespaceAttribute

    protected void processDefaultXPathNamespaceAttribute(String ns)

  Process the [xsl:]xpath-default-namespace attribute if there is one

  Parameters:
    `ns` - the namespace URI of the attribute required (the default namespace or the XSLT namespace.)

### getDefaultXPathNamespace

    protected String getDefaultXPathNamespace()

  Get the default XPath namespace for elements and types

  Returns:
    the default namespace for elements and types. Return `NamespaceConstant.NULL` for the non-namespace

### getSchemaType

    public SchemaType getSchemaType(String typeAtt)
                             throws XPathException

  Get the Schema type definition for a type named in the stylesheet (in a "type" attribute).

  Parameters:
    `typeAtt` - the value of the type attribute
  Returns:
    the corresponding schema type
  Throws:
    `XPathException` - if the type is not declared in an imported schema, or is not a built-in type

### getTypeAnnotation

    public int getTypeAnnotation(SchemaType schemaType)

  Get the type annotation to use for a given schema type

  Parameters:
    `schemaType` - the schema type
  Returns:
    the corresponding numeric type annotation

### validate

    public void validate(Declaration decl)
                  throws XPathException

  Check that the stylesheet element is valid. This is called once for each element, after the entire tree has been built. As well as validation, it can perform first-time initialisation. The default implementation does nothing; it is normally overriden in subclasses.

  Parameters:
    `decl` -
  Throws:
    `XPathException`

### postValidate

    public void postValidate()
                      throws XPathException

  Hook to allow additional validation of a parent element immediately after its children have been validated.

  Throws:
    `XPathException`

### index

    protected void index(Declaration decl,
                         PrincipalStylesheetModule top)
                  throws XPathException

  Method supplied by declaration elements to add themselves to a stylesheet-level index

  Parameters:
    `decl` - the Declaration being indexed. (This corresponds to the StyleElement object except in cases where one module is imported several times with different precedence.)
    `top` - the outermost XSLStylesheet element
  Throws:
    `XPathException`

### typeCheck

    public Expression typeCheck(String name,
                                Expression exp)
                         throws XPathException

  Type-check an expression. This is called to check each expression while the containing instruction is being validated. It is not just a static type-check, it also adds code to perform any necessary run-time type checking and/or conversion.

  Parameters:
    `name` - the name of the attribute containing the expression to be checked (used for diagnostics)
    `exp` - the expression to be checked
  Returns:
    the (possibly rewritten) expression after type checking
  Throws:
    `XPathException`

### allocateSlots

    public void allocateSlots(Expression exp)

  Allocate slots in the local stack frame to range variables used in an XPath expression

  Parameters:
    `exp` - the XPath expression for which slots are to be allocated

### allocatePatternSlots

    public void allocatePatternSlots(int slots)

  Allocate space for range variables within predicates in the match pattern. The xsl:template element has no XPath expressions among its attributes, so if this method is called on this object it can only be because there are variables used in the match pattern. We work out how many slots are needed for the match pattern in each template rule, and then apply-templates can allocate a stack frame that is large enough for the most demanding match pattern in the entire stylesheet.

  Parameters:
    `slots` - the number of slots required

### typeCheck

    public Pattern typeCheck(String name,
                             Pattern pattern)
                      throws XPathException

  Type-check a pattern. This is called to check each pattern while the containing instruction is being validated. It is not just a static type-check, it also adds code to perform any necessary run-time type checking and/or conversion.

  Parameters:
    `name` - the name of the attribute holding the pattern, for example "match": used in diagnostics
    `pattern` - the compiled pattern
  Returns:
    the original pattern, or a substitute pattern if it has been rewritten
  Throws:
    `XPathException`

### fixupReferences

    public void fixupReferences()
                         throws XPathException

  Fix up references from XPath expressions. Overridden for function declarations and variable declarations

  Throws:
    `XPathException`

### getContainingSlotManager

    public SlotManager getContainingSlotManager()

  Get the SlotManager for the containing Procedure definition

  Returns:
    the SlotManager associated with the containing Function, Template, etc, or null if there is no such containing Function, Template etc.

### validateSubtree

    public void validateSubtree(Declaration decl)
                         throws XPathException

  Recursive walk through the stylesheet to validate all nodes

  Parameters:
    `decl` -
  Throws:
    `XPathException`

### validateChildren

    protected void validateChildren(Declaration decl)
                             throws XPathException

  Validate the children of this node, recursively. Overridden for top-level data elements.

  Parameters:
    `decl` -
  Throws:
    `XPathException`

### isPermittedChild

    protected boolean isPermittedChild(StyleElement child)

  Check whether a given child is permitted for this element. This method is used when a non-instruction child element such as xsl:sort is encountered in a context where instructions would normally be expected.

  Parameters:
    `child` - the child that may or may not be permitted
  Returns:
    true if the child is permitted.

### getPreparedStylesheet

    public PreparedStylesheet getPreparedStylesheet()

  Get the PreparedStylesheet object.

  Returns:
    the PreparedStylesheet to which this stylesheet element belongs. Exceptionally (with early errors in a simplified stylesheet module) return null.

### getPrincipalStylesheetModule

    public PrincipalStylesheetModule getPrincipalStylesheetModule()

  Get the principal stylesheet module

  Returns:
    the principal stylesheet module

### checkSortComesFirst

    protected void checkSortComesFirst(boolean sortRequired)
                                throws XPathException

  Check that among the children of this element, any xsl:sort elements precede any other elements

  Parameters:
    `sortRequired` - true if there must be at least one xsl:sort element
  Throws:
    `XPathException` - if invalid

### checkTopLevel

    public void checkTopLevel(String errorCode)
                       throws XPathException

  Convenience method to check that the stylesheet element is at the top level

  Parameters:
    `errorCode` - the error to throw if it is not at the top level; defaults to XTSE0010 if the value is null
  Throws:
    `XPathException` - if not at top level

### checkEmpty

    public void checkEmpty()
                    throws XPathException

  Convenience method to check that the stylesheet element is empty

  Throws:
    `XPathException` - if it is not empty

### reportAbsence

    public void reportAbsence(String attribute)
                       throws XPathException

  Convenience method to report the absence of a mandatory attribute

  Parameters:
    `attribute` - the name of the attribute whose absence is to be reported
  Throws:
    `XPathException` - if the attribute is missing

### compile

    public abstract Expression compile(Executable exec,
                                       Declaration decl)
                                throws XPathException

  Compile the instruction on the stylesheet tree into an executable instruction for use at run-time.

  Parameters:
    `exec` - the Executable
    `decl` - the containing top-level declaration, for example xsl:function or xsl:template
  Returns:
    either a ComputedExpression, or null. The value null is returned when compiling an instruction that returns a no-op, or when compiling a top-level object such as an xsl:template that compiles into something other than an instruction.
  Throws:
    `XPathException`

### compileSequenceConstructor

    public Expression compileSequenceConstructor(Executable exec,
                                                 Declaration decl,
                                                 SequenceIterator iter,
                                                 boolean includeParams)
                                          throws XPathException

  Compile the children of this instruction on the stylesheet tree, adding the subordinate instructions to the parent instruction on the execution tree.

  Parameters:
    `exec` - the Executable
    `decl` - the Declaration of the containing top-level stylesheet element
    `iter` - Iterator over the children. This is used in the case where there are children that are not part of the sequence constructor, for example the xsl:sort children of xsl:for-each; the iterator can be positioned past such elements.
    `includeParams` - true if xsl:param elements are to be treated as child instructions (true for templates but not for functions) @return an Expression tree representing the children of this instruction
  Throws:
    `XPathException`

### makeTraceInstruction

    protected static TraceWrapper makeTraceInstruction(StyleElement source,
                                                       Expression child)

  Create a trace instruction to wrap a real instruction

  Parameters:
    `source` - the parent element
    `child` - the compiled expression tree for the instruction to be traced
  Returns:
    a wrapper instruction that performs the tracing (if activated at run-time)

### fallbackProcessing

    protected Expression fallbackProcessing(Executable exec,
                                            Declaration decl,
                                            StyleElement instruction)
                                     throws XPathException

  Perform fallback processing. Generate fallback code for an extension instruction that is not recognized by the implementation.

  Parameters:
    `exec` - the Executable
    `decl` - the Declaration of the top-level element containing the extension instruction
    `instruction` - The unknown extension instruction @return the expression tree representing the fallback code
  Throws:
    `XPathException`

### allocateLocationId

    protected int allocateLocationId(String systemId,
                                     int lineNumber)

  Allocate a location identifier

  Parameters:
    `systemId` - identifies the module containing the instruction
    `lineNumber` - the line number of the instruction
  Returns:
    an integer location ID which can be used to report the location of the instruction, by reference to a `LocationProvider`

### makeSortKeys

    protected SortKeyDefinition[] makeSortKeys(Declaration decl)
                                        throws XPathException

  Construct sort keys for a SortedIterator

  Parameters:
    `decl` -
  Returns:
    an array of SortKeyDefinition objects if there are any sort keys; or null if there are none.
  Throws:
    `XPathException`

### getAttributeSets

    protected AttributeSet[] getAttributeSets(String use,
                                              List<Declaration> list)
                                       throws XPathException

  Get the list of attribute-sets associated with this element. This is used for xsl:element, xsl:copy, xsl:attribute-set, and on literal result elements

  Parameters:
    `use` - the original value of the [xsl:]use-attribute-sets attribute
    `list` - an empty list to hold the list of XSLAttributeSet elements in the stylesheet tree. Or null, if these are not required.
  Returns:
    an array of AttributeList instructions representing the compiled attribute sets
  Throws:
    `XPathException`

### getWithParamInstructions

    protected WithParam[] getWithParamInstructions(Executable exec,
                                                   Declaration decl,
                                                   boolean tunnel,
                                                   Expression caller)
                                            throws XPathException

  Get the list of xsl:with-param elements for a calling element (apply-templates, call-template, apply-imports, next-match). This method can be used to get either the tunnel parameters, or the non-tunnel parameters.

  Parameters:
    `exec` - the Executable
    `decl` -
    `tunnel` - true if the tunnel="yes" parameters are wanted, false to get
    `caller` - the calling instruction (for example xsl:apply-templates), used only for its location information @return an array of WithParam objects for either the ordinary parameters or the tunnel parameters
  Throws:
    `XPathException`

### compileError

    protected void compileError(XPathException error)
                         throws XPathException

  Report an error with diagnostic information

  Parameters:
    `error` - contains information about the error
  Throws:
    `XPathException` - always, after reporting the error to the ErrorListener

### compileError

    protected void compileError(String message)
                         throws XPathException

  Report a static error in the stylesheet

  Parameters:
    `message` - the error message
  Throws:
    `XPathException` - always, after reporting the error to the ErrorListener

### compileError

    protected void compileError(String message,
                                StructuredQName errorCode)
                         throws XPathException

  Compile time error, specifying an error code

  Parameters:
    `message` - the error message
    `errorCode` - the error code. May be null if not known or not defined
  Throws:
    `XPathException`

### compileError

    protected void compileError(String message,
                                String errorCode)
                         throws XPathException

  Compile time error, specifying an error code

  Parameters:
    `message` - the error message
    `errorCode` - the error code. May be null if not known or not defined
  Throws:
    `XPathException`

### undeclaredNamespaceError

    protected void undeclaredNamespaceError(String prefix,
                                            String errorCode)
                                     throws XPathException

  Throws:
    `XPathException`

### compileWarning

    protected void compileWarning(String message,
                                  StructuredQName errorCode)
                           throws XPathException

  Throws:
    `XPathException`

### compileWarning

    protected void compileWarning(String message,
                                  String errorCode)
                           throws XPathException

  Throws:
    `XPathException`

### issueWarning

    protected void issueWarning(TransformerException error)

  Report a warning to the error listener

  Parameters:
    `error` - an exception containing the warning text

### issueWarning

    protected void issueWarning(String message,
                                SourceLocator locator)

  Report a warning to the error listener

  Parameters:
    `message` - the warning message text
    `locator` - the location of the problem in the source stylesheet

### isTopLevel

    public boolean isTopLevel()

  Test whether this is a top-level element

  Returns:
    true if the element is a child of the xsl:stylesheet element

### bindVariable

    public XSLVariableDeclaration bindVariable(StructuredQName qName)

  Bind a variable used in this element to the compiled form of the XSLVariable element in which it is declared

  Parameters:
    `qName` - The name of the variable
  Returns:
    the XSLVariableDeclaration (that is, an xsl:variable or xsl:param instruction) for the variable, or null if no declaration of the variable can be found

### seesAvuncularVariables

    protected boolean seesAvuncularVariables()

  Ask whether variables declared in an "uncle" element are visible.

  Returns:
    true for all elements except xsl:fallback and saxon:catch

### getConstructType

    public int getConstructType()

  Get the type of construct. This will be a constant in class `Location`. This method is part of the `InstructionInfo` interface

  Specified by:
    `getConstructType` in interface `InstructionInfo`
  Returns:
    an integer identifying the kind of construct

### getObjectName

    public StructuredQName getObjectName()

  Get a name identifying the object of the expression, for example a function name, template name, variable name, key name, element name, etc. This is used only where the name is known statically. If there is no name, the value will be null.

  Specified by:
    `getObjectName` in interface `InstructionInfo`
  Returns:
    the name of the object declared in this element, if any

### setObjectName

    public void setObjectName(StructuredQName qName)

  Set the object name, for example the name of a function, variable, or template declared on this element

  Parameters:
    `qName` - the object name as a QName

### getProperty

    public Object getProperty(String name)

  Get the value of a particular property of the instruction. This is part of the `InstructionInfo` interface for run-time tracing and debugging. The properties available include all the attributes of the source instruction (named by the attribute name): these are all provided as string values.

  Specified by:
    `getProperty` in interface `InstructionInfo`
  Parameters:
    `name` - The name of the required property
  Returns:
    The value of the requested property, or null if the property is not available

### getProperties

    public Iterator getProperties()

  Get an iterator over all the properties available. The values returned by the iterator will be of type String, and each string can be supplied as input to the getProperty() method to retrieve the value of the property.

  Specified by:
    `getProperties` in interface `InstructionInfo`
  Returns:
    an iterator over the properties.

### getSystemId

    public String getSystemId(long locationId)

  Description copied from interface: `LocationProvider`
  Get the URI of the document, entity, or module containing a particular location

  Specified by:
    `getSystemId` in interface `LocationProvider`
  Parameters:
    `locationId` - identifier of the location in question (as passed down the Receiver pipeline)
  Returns:
    the URI of the document, XML entity or module. For a SourceLocationProvider this will be the URI of the document or entity (the URI that would be the base URI if there were no xml:base attributes). In other cases it may identify the query or stylesheet module currently being executed.

### getLineNumber

    public int getLineNumber(long locationId)

  Description copied from interface: `LocationProvider`
  Get the line number within the document, entity or module containing a particular location

  Specified by:
    `getLineNumber` in interface `LocationProvider`
  Parameters:
    `locationId` - identifier of the location in question (as passed down the Receiver pipeline)
  Returns:
    the line number within the document, entity or module, or -1 if no information is available.

### getColumnNumber

    public int getColumnNumber(long locationId)

  Description copied from interface: `LocationProvider`
  Get the column number within the document, entity, or module containing a particular location

  Specified by:
    `getColumnNumber` in interface `LocationProvider`
  Parameters:
    `locationId` - identifier of the location in question (as passed down the Receiver pipeline)
  Returns:
    the column number within the document, entity, or module, or -1 if this is not available

### getHostLanguage

    public int getHostLanguage()

  Get the host language (XSLT, XQuery, XPath) used to implement the code in this container

  Specified by:
    `getHostLanguage` in interface `Container`
  Returns:
    typically `Configuration.XSLT` or `Configuration.XQUERY`

### isActionCompleted

    public boolean isActionCompleted(int action)

  Ask if an action on this StyleElement has been completed

  Parameters:
    `action` - for example ACTION_VALIDATE
  Returns:
    true if the action has already been performed

### setActionCompleted

    public void setActionCompleted(int action)

  Say that an action on this StyleElement has been completed

  Parameters:
    `action` - for example ACTION_VALIDATE

### getSequenceNumber

    protected final long getSequenceNumber()

  Get the node sequence number (in document order). Sequence numbers are monotonic but not consecutive. In the current implementation, parent nodes (elements and document nodes) have a zero least-significant word, while namespaces, attributes, text nodes, comments, and PIs have the top word the same as their owner and the bottom half reflecting their relative position. For nodes added by XQUery Update, the sequence number is -1L

  Overrides:
    `getSequenceNumber` in class `NodeImpl`
  Returns:
    the sequence number if there is one, or -1L otherwise.

### getRawSequenceNumber

    protected final int getRawSequenceNumber()

### setRawSequenceNumber

    protected final void setRawSequenceNumber(int seq)

### setChildren

    protected final void setChildren(Object children)

  Set the children of this node

  Parameters:
    `children` - null if there are no children, a single NodeInfo if there is one child, an array of NodeInfo if there are multiple children

### hasChildNodes

    public final boolean hasChildNodes()

  Determine if the node has any children.

  Specified by:
    `hasChildNodes` in interface `NodeInfo`
  Overrides:
    `hasChildNodes` in class `NodeImpl`
  Returns:
    `true` if the node has any children, `false` if the node has no children.

### getNumberOfChildren

    public final int getNumberOfChildren()

  Determine how many children the node has

  Returns:
    the number of children of this parent node

### enumerateChildren

    protected final AxisIterator enumerateChildren(NodeTest test)

  Get an enumeration of the children of this node

  Parameters:
    `test` - A NodeTest to be satisfied by the child nodes, or null if all child node are to be returned
  Returns:
    an iterator over the children of this node

### getFirstChild

    public final NodeInfo getFirstChild()

  Get the first child node of the element

  Overrides:
    `getFirstChild` in class `NodeImpl`
  Returns:
    the first child node of the required type, or null if there are no children

### getLastChild

    public final NodeInfo getLastChild()

  Get the last child node of the element

  Overrides:
    `getLastChild` in class `NodeImpl`
  Returns:
    the last child of the element, or null if there are no children

### getNthChild

    protected final NodeImpl getNthChild(int n)

  Get the nth child node of the element (numbering from 0)

  Parameters:
    `n` - identifies the required child
  Returns:
    the last child of the element, or null if there is no n'th child

### removeChild

    protected void removeChild(NodeImpl child)

  Remove a given child

  Parameters:
    `child` - the child to be removed

### getStringValue

    public String getStringValue()

  Return the string-value of the node, that is, the concatenation of the character content of all descendent elements and text nodes.

  Returns:
    the accumulated character content of the element, including descendant elements.
  See Also:
    `Item.getStringValueCS()`

### getStringValueCS

    public CharSequence getStringValueCS()

  Description copied from class: `NodeImpl`
  Get the value of the item as a CharSequence. This is in some cases more efficient than the version of the method that returns a String.

  Specified by:
    `getStringValueCS` in interface `Item`
  Specified by:
    `getStringValueCS` in interface `ValueRepresentation`
  Overrides:
    `getStringValueCS` in class `NodeImpl`
  Returns:
    the string value of the item
  See Also:
    `Item.getStringValue()`

### addChild

    protected void addChild(NodeImpl node,
                            int index)

  Add a child node to this node. For system use only. Note: normalizing adjacent text nodes is the responsibility of the caller.

  Parameters:
    `node` - the node to be added as a child of this node. This must be an instance of `NodeImpl`. It will be modified as a result of this call (by setting its parent property and sibling position)
    `index` - the position where the child is to be added

### insertChildren

    public void insertChildren(NodeInfo[] source,
                               boolean atStart,
                               boolean inherit)

  Insert a sequence of nodes as children of this node.

  This method takes no action unless the target node is a document node or element node. It also takes no action in respect of any supplied nodes that are not elements, text nodes, comments, or processing instructions.

  The supplied nodes will form the new children. Adjacent text nodes will be merged, and zero-length text nodes removed. The supplied nodes may be modified in situ, for example to change their parent property and to add namespace bindings, or they may be copied, at the discretion of the implementation.

  Specified by:
    `insertChildren` in interface `MutableNodeInfo`
  Overrides:
    `insertChildren` in class `NodeImpl`
  Parameters:
    `source` - the nodes to be inserted. The implementation determines what implementation classes of node it will accept; this implementation will accept text, comment, and processing instruction nodes belonging to any implementation, but elements must be instances of `ElementImpl`. The supplied nodes will be modified in situ, for example to change their parent property and to add namespace bindings, if they are instances of `ElementImpl`; otherwise they will be copied. If the nodes are copied, then on return the supplied source array will contain the copy rather than the original.
    `atStart` - true if the new nodes are to be inserted before existing children; false if they are to be inserted after existing children
    `inherit` - true if the inserted nodes are to inherit the namespaces of their new parent; false if such namespaces are to be undeclared
  Throws:
    `IllegalArgumentException` - if the supplied nodes use a node implementation that this implementation does not accept.

### insertChildrenAt

    protected void insertChildrenAt(NodeInfo[] source,
                                    int index,
                                    boolean inherit)

  Insert children before or after a given existing child

  Parameters:
    `source` - the children to be inserted. We allow any kind of text, comment, or processing instruction node, but element nodes must be instances of this NodeInfo implementation.
    `index` - the position before which they are to be inserted: 0 indicates insertion before the first child, 1 insertion before the second child, and so on.
    `inherit` - true if the inserted nodes are to inherit the namespaces that are in-scope for their new parent; false if such namespaces should be undeclared on the children

### replaceChildrenAt

    protected void replaceChildrenAt(NodeInfo[] source,
                                     int index,
                                     boolean inherit)

  Replace child at a given index by new children

  Parameters:
    `source` - the children to be inserted
    `index` - the position at which they are to be inserted: 0 indicates replacement of the first child, replacement of the second child, and so on. The effect is undefined if index is out of range
    `inherit` - set to true if the new child elements are to inherit the in-scope namespaces of their new parent
  Throws:
    `IllegalArgumentException` - if any of the replacement nodes is not an element, text, comment, or processing instruction node

### compact

    public void compact(int size)

  Compact the space used by this node

  Parameters:
    `size` - the number of actual children

Copyright (c) 2004-2010 Saxonica Limited. All rights reserved.