Sophie

Sophie

distrib > Mageia > 7 > armv7hl > by-pkgid > b3bdfe6d859a3d6920ff2c44b38e9a6f > files > 920

saxon-manual-9.4.0.9-2.mga7.noarch.rpm

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<!--NewPage-->
<HTML>
<HEAD>
<!-- Generated by javadoc (build 1.6.0_18) on Fri Dec 09 20:47:42 GMT 2011 -->
<TITLE>
While
</TITLE>

<META NAME="date" CONTENT="2011-12-09">

<LINK REL ="stylesheet" TYPE="text/css" HREF="../../../stylesheet.css" TITLE="Style">

<SCRIPT type="text/javascript">
function windowTitle()
{
    if (location.href.indexOf('is-external=true') == -1) {
        parent.document.title="While";
    }
}
</SCRIPT>
<NOSCRIPT>
</NOSCRIPT>

</HEAD>

<BODY BGCOLOR="white" onload="windowTitle();">
<HR>


<!-- ========= START OF TOP NAVBAR ======= -->
<A NAME="navbar_top"><!-- --></A>
<A HREF="#skip-navbar_top" title="Skip navigation links"></A>
<TABLE BORDER="0" WIDTH="100%" CELLPADDING="1" CELLSPACING="0" SUMMARY="">
<TR>
<TD COLSPAN=2 BGCOLOR="#EEEEFF" CLASS="NavBarCell1">
<A NAME="navbar_top_firstrow"><!-- --></A>
<TABLE BORDER="0" CELLPADDING="0" CELLSPACING="3" SUMMARY="">
  <TR ALIGN="center" VALIGN="top">
  <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1">    <A HREF="../../../overview-summary.html"><FONT CLASS="NavBarFont1"><B>Overview</B></FONT></A>&nbsp;</TD>
  <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1">    <A HREF="package-summary.html"><FONT CLASS="NavBarFont1"><B>Package</B></FONT></A>&nbsp;</TD>
  <TD BGCOLOR="#FFFFFF" CLASS="NavBarCell1Rev"> &nbsp;<FONT CLASS="NavBarFont1Rev"><B>Class</B></FONT>&nbsp;</TD>
  <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1">    <A HREF="package-tree.html"><FONT CLASS="NavBarFont1"><B>Tree</B></FONT></A>&nbsp;</TD>
  <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1">    <A HREF="../../../deprecated-list.html"><FONT CLASS="NavBarFont1"><B>Deprecated</B></FONT></A>&nbsp;</TD>
  <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1">    <A HREF="../../../index-all.html"><FONT CLASS="NavBarFont1"><B>Index</B></FONT></A>&nbsp;</TD>
  <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1">    <A HREF="../../../help-doc.html"><FONT CLASS="NavBarFont1"><B>Help</B></FONT></A>&nbsp;</TD>
  </TR>
</TABLE>
</TD>
<TD ALIGN="right" VALIGN="top" ROWSPAN=3><EM>
</EM>
</TD>
</TR>

<TR>
<TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2">
&nbsp;<A HREF="../../../com/saxonica/expr/TryCatch.CatchClause.html" title="class in com.saxonica.expr"><B>PREV CLASS</B></A>&nbsp;
&nbsp;<A HREF="../../../com/saxonica/expr/XPath30Parser.html" title="class in com.saxonica.expr"><B>NEXT CLASS</B></A></FONT></TD>
<TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2">
  <A HREF="../../../index.html?com/saxonica/expr/While.html" target="_top"><B>FRAMES</B></A>  &nbsp;
&nbsp;<A HREF="While.html" target="_top"><B>NO FRAMES</B></A>  &nbsp;
&nbsp;<SCRIPT type="text/javascript">
  <!--
  if(window==top) {
    document.writeln('<A HREF="../../../allclasses-noframe.html"><B>All Classes</B></A>');
  }
  //-->
</SCRIPT>
<NOSCRIPT>
  <A HREF="../../../allclasses-noframe.html"><B>All Classes</B></A>
</NOSCRIPT>


</FONT></TD>
</TR>
<TR>
<TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2">
  SUMMARY:&nbsp;NESTED&nbsp;|&nbsp;<A HREF="#fields_inherited_from_class_net.sf.saxon.expr.Expression">FIELD</A>&nbsp;|&nbsp;<A HREF="#constructor_summary">CONSTR</A>&nbsp;|&nbsp;<A HREF="#method_summary">METHOD</A></FONT></TD>
<TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2">
DETAIL:&nbsp;FIELD&nbsp;|&nbsp;<A HREF="#constructor_detail">CONSTR</A>&nbsp;|&nbsp;<A HREF="#method_detail">METHOD</A></FONT></TD>
</TR>
</TABLE>
<A NAME="skip-navbar_top"></A>
<!-- ========= END OF TOP NAVBAR ========= -->

<HR>
<!-- ======== START OF CLASS DATA ======== -->
<H2>
<FONT SIZE="-1">
com.saxonica.expr</FONT>
<BR>
Class While</H2>
<PRE>
<A HREF="http://download.oracle.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">java.lang.Object</A>
  <IMG SRC="../../../resources/inherit.gif" ALT="extended by "><A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">net.sf.saxon.expr.Expression</A>
      <IMG SRC="../../../resources/inherit.gif" ALT="extended by "><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html" title="class in net.sf.saxon.expr.instruct">net.sf.saxon.expr.instruct.Instruction</A>
          <IMG SRC="../../../resources/inherit.gif" ALT="extended by "><B>com.saxonica.expr.While</B>
</PRE>
<DL>
<DT><B>All Implemented Interfaces:</B> <DD><A HREF="http://download.oracle.com/javase/6/docs/api/java/io/Serializable.html?is-external=true" title="class or interface in java.io">Serializable</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/javax/xml/transform/SourceLocator.html?is-external=true" title="class or interface in javax.xml.transform">SourceLocator</A>, <A HREF="../../../net/sf/saxon/event/LocationProvider.html" title="interface in net.sf.saxon.event">LocationProvider</A>, <A HREF="../../../net/sf/saxon/event/SaxonLocator.html" title="interface in net.sf.saxon.event">SaxonLocator</A>, <A HREF="../../../net/sf/saxon/expr/instruct/TailCallReturner.html" title="interface in net.sf.saxon.expr.instruct">TailCallReturner</A>, <A HREF="../../../net/sf/saxon/trace/InstructionInfo.html" title="interface in net.sf.saxon.trace">InstructionInfo</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/org/xml/sax/Locator.html?is-external=true" title="class or interface in org.xml.sax">Locator</A></DD>
</DL>
<HR>
<DL>
<DT><PRE>public class <B>While</B><DT>extends <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html" title="class in net.sf.saxon.expr.instruct">Instruction</A></DL>
</PRE>

<P>
Handler for saxon:while elements in stylesheet. <br>
 The saxon:while element has a mandatory attribute test, a boolean expression.
 The content is output repeatedly so long as the test condition is true.
<P>

<P>
<DL>
<DT><B>See Also:</B><DD><A HREF="../../../serialized-form.html#com.saxonica.expr.While">Serialized Form</A></DL>
<HR>

<P>
<!-- =========== FIELD SUMMARY =========== -->

<A NAME="field_summary"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="2"><FONT SIZE="+2">
<B>Field Summary</B></FONT></TH>
</TR>
</TABLE>
&nbsp;<A NAME="fields_inherited_from_class_net.sf.saxon.expr.Expression"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TH ALIGN="left"><B>Fields inherited from class net.sf.saxon.expr.<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></B></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="../../../net/sf/saxon/expr/Expression.html#EFFECTIVE_BOOLEAN_VALUE">EFFECTIVE_BOOLEAN_VALUE</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#EVALUATE_METHOD">EVALUATE_METHOD</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#EVENT_FEED_METHOD">EVENT_FEED_METHOD</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#ITEM_FEED_METHOD">ITEM_FEED_METHOD</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#ITERATE_METHOD">ITERATE_METHOD</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#locationId">locationId</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#MAX_SEQUENCE_LENGTH">MAX_SEQUENCE_LENGTH</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#MAX_STRING_LENGTH">MAX_STRING_LENGTH</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#PROCESS_METHOD">PROCESS_METHOD</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#PUSH_SELECTION">PUSH_SELECTION</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#staticProperties">staticProperties</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#UNBOUNDED_LOWER">UNBOUNDED_LOWER</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#UNBOUNDED_UPPER">UNBOUNDED_UPPER</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#WATCH_METHOD">WATCH_METHOD</A></CODE></TD>
</TR>
</TABLE>
&nbsp;
<!-- ======== CONSTRUCTOR SUMMARY ======== -->

<A NAME="constructor_summary"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="2"><FONT SIZE="+2">
<B>Constructor Summary</B></FONT></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#While(net.sf.saxon.expr.Expression, net.sf.saxon.expr.Expression)">While</A></B>(<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A>&nbsp;test,
      <A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A>&nbsp;action)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</TD>
</TR>
</TABLE>
&nbsp;
<!-- ========== METHOD SUMMARY =========== -->

<A NAME="method_summary"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="2"><FONT SIZE="+2">
<B>Method Summary</B></FONT></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#copy()">copy</A></B>()</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Copy an expression.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#createsNewNodes()">createsNewNodes</A></B>()</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Determine whether this instruction creates new nodes.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#explain(net.sf.saxon.trace.ExpressionPresenter)">explain</A></B>(<A HREF="../../../net/sf/saxon/trace/ExpressionPresenter.html" title="class in net.sf.saxon.trace">ExpressionPresenter</A>&nbsp;out)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Diagnostic print of expression structure.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#getActionExpression()">getActionExpression</A></B>()</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Get the action expression (the content of the for-each)</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;int</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#getInstructionNameCode()">getInstructionNameCode</A></B>()</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Get the name of this instruction for diagnostic and tracing purposes</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;<A HREF="../../../net/sf/saxon/type/ItemType.html" title="interface in net.sf.saxon.type">ItemType</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#getItemType(net.sf.saxon.type.TypeHierarchy)">getItemType</A></B>(<A HREF="../../../net/sf/saxon/type/TypeHierarchy.html" title="class in net.sf.saxon.type">TypeHierarchy</A>&nbsp;th)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Get the item type of the items returned by evaluating this instruction</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#hasLoopingSubexpression(net.sf.saxon.expr.Expression)">hasLoopingSubexpression</A></B>(<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A>&nbsp;child)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Given an expression that is an immediate child of this expression, test whether
 the evaluation of the parent expression causes the child expression to be
 evaluated repeatedly</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;<A HREF="http://download.oracle.com/javase/6/docs/api/java/util/Iterator.html?is-external=true" title="class or interface in java.util">Iterator</A>&lt;<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A>&gt;</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#iterateSubExpressions()">iterateSubExpressions</A></B>()</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Get all the XPath expressions associated with this instruction
 (in XSLT terms, the expression present on attributes of the instruction,
 as distinct from the child instructions in a sequence construction)</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#optimize(net.sf.saxon.expr.parser.ExpressionVisitor, net.sf.saxon.expr.parser.ExpressionVisitor.ContextItemType)">optimize</A></B>(<A HREF="../../../net/sf/saxon/expr/parser/ExpressionVisitor.html" title="class in net.sf.saxon.expr.parser">ExpressionVisitor</A>&nbsp;visitor,
         <A HREF="../../../net/sf/saxon/expr/parser/ExpressionVisitor.ContextItemType.html" title="class in net.sf.saxon.expr.parser">ExpressionVisitor.ContextItemType</A>&nbsp;contextItemType)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Perform optimisation of an expression and its subexpressions.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;<A HREF="../../../net/sf/saxon/expr/instruct/TailCall.html" title="interface in net.sf.saxon.expr.instruct">TailCall</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#processLeavingTail(net.sf.saxon.expr.XPathContext)">processLeavingTail</A></B>(<A HREF="../../../net/sf/saxon/expr/XPathContext.html" title="interface in net.sf.saxon.expr">XPathContext</A>&nbsp;context)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ProcessLeavingTail: called to do the real work of this instruction.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>protected &nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#promoteInst(net.sf.saxon.expr.parser.PromotionOffer)">promoteInst</A></B>(<A HREF="../../../net/sf/saxon/expr/parser/PromotionOffer.html" title="class in net.sf.saxon.expr.parser">PromotionOffer</A>&nbsp;offer)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Handle promotion offers, that is, non-local tree rewrites.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#replaceSubExpression(net.sf.saxon.expr.Expression, net.sf.saxon.expr.Expression)">replaceSubExpression</A></B>(<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A>&nbsp;original,
                     <A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A>&nbsp;replacement)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Replace one subexpression by a replacement subexpression</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#simplify(net.sf.saxon.expr.parser.ExpressionVisitor)">simplify</A></B>(<A HREF="../../../net/sf/saxon/expr/parser/ExpressionVisitor.html" title="class in net.sf.saxon.expr.parser">ExpressionVisitor</A>&nbsp;visitor)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Simplify an expression.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/saxonica/expr/While.html#typeCheck(net.sf.saxon.expr.parser.ExpressionVisitor, net.sf.saxon.expr.parser.ExpressionVisitor.ContextItemType)">typeCheck</A></B>(<A HREF="../../../net/sf/saxon/expr/parser/ExpressionVisitor.html" title="class in net.sf.saxon.expr.parser">ExpressionVisitor</A>&nbsp;visitor,
          <A HREF="../../../net/sf/saxon/expr/parser/ExpressionVisitor.ContextItemType.html" title="class in net.sf.saxon.expr.parser">ExpressionVisitor.ContextItemType</A>&nbsp;contextItemType)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Perform type checking of an expression and its subexpressions.</TD>
</TR>
</TABLE>
&nbsp;<A NAME="methods_inherited_from_class_net.sf.saxon.expr.instruct.Instruction"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TH ALIGN="left"><B>Methods inherited from class net.sf.saxon.expr.instruct.<A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html" title="class in net.sf.saxon.expr.instruct">Instruction</A></B></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#assembleParams(net.sf.saxon.expr.XPathContext, net.sf.saxon.expr.instruct.WithParam[])">assembleParams</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#assembleTunnelParams(net.sf.saxon.expr.XPathContext, net.sf.saxon.expr.instruct.WithParam[])">assembleTunnelParams</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#computeCardinality()">computeCardinality</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#computeSpecialProperties()">computeSpecialProperties</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#dynamicError(javax.xml.transform.SourceLocator, net.sf.saxon.trans.XPathException, net.sf.saxon.expr.XPathContext)">dynamicError</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#evaluateAsString(net.sf.saxon.expr.XPathContext)">evaluateAsString</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#evaluateItem(net.sf.saxon.expr.XPathContext)">evaluateItem</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#getConstructType()">getConstructType</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#getExpressionName()">getExpressionName</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#getImplementationMethod()">getImplementationMethod</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#getInstructionName()">getInstructionName</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#getIteratorFromProcessMethod(net.sf.saxon.expr.XPathContext)">getIteratorFromProcessMethod</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#getSourceLocator()">getSourceLocator</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#isXSLT()">isXSLT</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#iterate(net.sf.saxon.expr.XPathContext)">iterate</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#process(net.sf.saxon.expr.XPathContext)">process</A>, <A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#promote(net.sf.saxon.expr.parser.PromotionOffer, net.sf.saxon.expr.Expression)">promote</A></CODE></TD>
</TR>
</TABLE>
&nbsp;<A NAME="methods_inherited_from_class_net.sf.saxon.expr.Expression"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TH ALIGN="left"><B>Methods inherited from class net.sf.saxon.expr.<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></B></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="../../../net/sf/saxon/expr/Expression.html#addToPathMap(net.sf.saxon.expr.parser.PathMap, net.sf.saxon.expr.parser.PathMap.PathMapNodeSet)">addToPathMap</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#adoptChildExpression(net.sf.saxon.expr.Expression)">adoptChildExpression</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#checkForUpdatingSubexpressions()">checkForUpdatingSubexpressions</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#checkPermittedContents(net.sf.saxon.type.SchemaType, net.sf.saxon.expr.StaticContext, boolean)">checkPermittedContents</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#computeDependencies()">computeDependencies</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#computeStaticProperties()">computeStaticProperties</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#doPromotion(net.sf.saxon.expr.Expression, net.sf.saxon.expr.parser.PromotionOffer)">doPromotion</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#dynamicError(java.lang.String, java.lang.String, net.sf.saxon.expr.XPathContext)">dynamicError</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#effectiveBooleanValue(net.sf.saxon.expr.XPathContext)">effectiveBooleanValue</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#evaluatePendingUpdates(net.sf.saxon.expr.XPathContext, net.sf.saxon.expr.PendingUpdateList)">evaluatePendingUpdates</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#explain(java.io.OutputStream)">explain</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getCardinality()">getCardinality</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getColumnNumber()">getColumnNumber</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getColumnNumber(long)">getColumnNumber</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getContainer()">getContainer</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getDependencies()">getDependencies</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getEvaluationMethod()">getEvaluationMethod</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getExecutable()">getExecutable</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getHostLanguage()">getHostLanguage</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getIntegerBounds()">getIntegerBounds</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getIntrinsicDependencies()">getIntrinsicDependencies</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getLineNumber()">getLineNumber</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getLineNumber(long)">getLineNumber</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getLocationId()">getLocationId</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getLocationProvider()">getLocationProvider</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getObjectName()">getObjectName</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getProperties()">getProperties</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getProperty(java.lang.String)">getProperty</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getPublicId()">getPublicId</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getSlotsUsed()">getSlotsUsed</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getSpecialProperties()">getSpecialProperties</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getSystemId()">getSystemId</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#getSystemId(long)">getSystemId</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#hasVariableBinding(net.sf.saxon.expr.Binding)">hasVariableBinding</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#implementsStaticTypeCheck()">implementsStaticTypeCheck</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#isSubtreeExpression()">isSubtreeExpression</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#isUpdatingExpression()">isUpdatingExpression</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#isVacuousExpression()">isVacuousExpression</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#iterateEvents(net.sf.saxon.expr.XPathContext)">iterateEvents</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#iterateSameFocusSubExpressions()">iterateSameFocusSubExpressions</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#markTailFunctionCalls(net.sf.saxon.om.StructuredQName, int)">markTailFunctionCalls</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#resetLocalStaticProperties()">resetLocalStaticProperties</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#setContainer(net.sf.saxon.expr.Container)">setContainer</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#setEvaluationMethod(int)">setEvaluationMethod</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#setFiltered(boolean)">setFiltered</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#setFlattened(boolean)">setFlattened</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#setLocationId(int)">setLocationId</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#staticTypeCheck(net.sf.saxon.value.SequenceType, boolean, net.sf.saxon.expr.parser.RoleLocator, net.sf.saxon.TypeCheckerEnvironment)">staticTypeCheck</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#suppressValidation(int)">suppressValidation</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#toString()">toString</A>, <A HREF="../../../net/sf/saxon/expr/Expression.html#typeError(java.lang.String, java.lang.String, net.sf.saxon.expr.XPathContext)">typeError</A></CODE></TD>
</TR>
</TABLE>
&nbsp;<A NAME="methods_inherited_from_class_java.lang.Object"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TH ALIGN="left"><B>Methods inherited from class java.lang.<A HREF="http://download.oracle.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A></B></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="http://download.oracle.com/javase/6/docs/api/java/lang/Object.html?is-external=true#clone()" title="class or interface in java.lang">clone</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/java/lang/Object.html?is-external=true#equals(java.lang.Object)" title="class or interface in java.lang">equals</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/java/lang/Object.html?is-external=true#finalize()" title="class or interface in java.lang">finalize</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/java/lang/Object.html?is-external=true#getClass()" title="class or interface in java.lang">getClass</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/java/lang/Object.html?is-external=true#hashCode()" title="class or interface in java.lang">hashCode</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/java/lang/Object.html?is-external=true#notify()" title="class or interface in java.lang">notify</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/java/lang/Object.html?is-external=true#notifyAll()" title="class or interface in java.lang">notifyAll</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/java/lang/Object.html?is-external=true#wait()" title="class or interface in java.lang">wait</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/java/lang/Object.html?is-external=true#wait(long)" title="class or interface in java.lang">wait</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/java/lang/Object.html?is-external=true#wait(long, int)" title="class or interface in java.lang">wait</A></CODE></TD>
</TR>
</TABLE>
&nbsp;<A NAME="methods_inherited_from_class_javax.xml.transform.SourceLocator"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TH ALIGN="left"><B>Methods inherited from interface javax.xml.transform.<A HREF="http://download.oracle.com/javase/6/docs/api/javax/xml/transform/SourceLocator.html?is-external=true" title="class or interface in javax.xml.transform">SourceLocator</A></B></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="http://download.oracle.com/javase/6/docs/api/javax/xml/transform/SourceLocator.html?is-external=true#getColumnNumber()" title="class or interface in javax.xml.transform">getColumnNumber</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/javax/xml/transform/SourceLocator.html?is-external=true#getLineNumber()" title="class or interface in javax.xml.transform">getLineNumber</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/javax/xml/transform/SourceLocator.html?is-external=true#getPublicId()" title="class or interface in javax.xml.transform">getPublicId</A>, <A HREF="http://download.oracle.com/javase/6/docs/api/javax/xml/transform/SourceLocator.html?is-external=true#getSystemId()" title="class or interface in javax.xml.transform">getSystemId</A></CODE></TD>
</TR>
</TABLE>
&nbsp;
<P>

<!-- ========= CONSTRUCTOR DETAIL ======== -->

<A NAME="constructor_detail"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="1"><FONT SIZE="+2">
<B>Constructor Detail</B></FONT></TH>
</TR>
</TABLE>

<A NAME="While(net.sf.saxon.expr.Expression, net.sf.saxon.expr.Expression)"><!-- --></A><H3>
While</H3>
<PRE>
public <B>While</B>(<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A>&nbsp;test,
             <A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A>&nbsp;action)</PRE>
<DL>
</DL>

<!-- ============ METHOD DETAIL ========== -->

<A NAME="method_detail"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="1"><FONT SIZE="+2">
<B>Method Detail</B></FONT></TH>
</TR>
</TABLE>

<A NAME="getInstructionNameCode()"><!-- --></A><H3>
getInstructionNameCode</H3>
<PRE>
public int <B>getInstructionNameCode</B>()</PRE>
<DL>
<DD>Get the name of this instruction for diagnostic and tracing purposes
<P>
<DD><DL>
<DT><B>Overrides:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#getInstructionNameCode()">getInstructionNameCode</A></CODE> in class <CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html" title="class in net.sf.saxon.expr.instruct">Instruction</A></CODE></DL>
</DD>
<DD><DL>

<DT><B>Returns:</B><DD>the string "saxon:while"</DL>
</DD>
</DL>
<HR>

<A NAME="getActionExpression()"><!-- --></A><H3>
getActionExpression</H3>
<PRE>
public <A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A> <B>getActionExpression</B>()</PRE>
<DL>
<DD>Get the action expression (the content of the for-each)
<P>
<DD><DL>
</DL>
</DD>
</DL>
<HR>

<A NAME="simplify(net.sf.saxon.expr.parser.ExpressionVisitor)"><!-- --></A><H3>
simplify</H3>
<PRE>
public <A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A> <B>simplify</B>(<A HREF="../../../net/sf/saxon/expr/parser/ExpressionVisitor.html" title="class in net.sf.saxon.expr.parser">ExpressionVisitor</A>&nbsp;visitor)
                    throws <A HREF="../../../net/sf/saxon/trans/XPathException.html" title="class in net.sf.saxon.trans">XPathException</A></PRE>
<DL>
<DD>Simplify an expression. This performs any static optimization (by rewriting the expression
 as a different expression).
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#simplify(net.sf.saxon.expr.parser.ExpressionVisitor)">simplify</A></CODE> in class <CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html" title="class in net.sf.saxon.expr.instruct">Instruction</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>visitor</CODE> - an expression visitor
<DT><B>Returns:</B><DD>the simplified expression
<DT><B>Throws:</B>
<DD><CODE><A HREF="../../../net/sf/saxon/trans/XPathException.html" title="class in net.sf.saxon.trans">XPathException</A></CODE> - if an error is discovered during expression
     rewriting</DL>
</DD>
</DL>
<HR>

<A NAME="typeCheck(net.sf.saxon.expr.parser.ExpressionVisitor, net.sf.saxon.expr.parser.ExpressionVisitor.ContextItemType)"><!-- --></A><H3>
typeCheck</H3>
<PRE>
public <A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A> <B>typeCheck</B>(<A HREF="../../../net/sf/saxon/expr/parser/ExpressionVisitor.html" title="class in net.sf.saxon.expr.parser">ExpressionVisitor</A>&nbsp;visitor,
                            <A HREF="../../../net/sf/saxon/expr/parser/ExpressionVisitor.ContextItemType.html" title="class in net.sf.saxon.expr.parser">ExpressionVisitor.ContextItemType</A>&nbsp;contextItemType)
                     throws <A HREF="../../../net/sf/saxon/trans/XPathException.html" title="class in net.sf.saxon.trans">XPathException</A></PRE>
<DL>
<DD><B>Description copied from class: <CODE><A HREF="../../../net/sf/saxon/expr/Expression.html#typeCheck(net.sf.saxon.expr.parser.ExpressionVisitor, net.sf.saxon.expr.parser.ExpressionVisitor.ContextItemType)">Expression</A></CODE></B></DD>
<DD>Perform type checking of an expression and its subexpressions. This is the second phase of
 static optimization.

 <p>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.</p>

 <p>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.</p>

 <p>If the implementation returns a value other than "this", then it is required to ensure that
 the location information in the returned expression have been set up correctly.
 It should not rely on the caller to do this, although for historical reasons many callers do so.</p>
<P>
<DD><DL>
<DT><B>Overrides:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/Expression.html#typeCheck(net.sf.saxon.expr.parser.ExpressionVisitor, net.sf.saxon.expr.parser.ExpressionVisitor.ContextItemType)">typeCheck</A></CODE> in class <CODE><A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>visitor</CODE> - an expression visitor<DD><CODE>contextItemType</CODE> - 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
 <A HREF="../../../net/sf/saxon/type/Type.html#ITEM_TYPE"><CODE>Type.ITEM_TYPE</CODE></A>
<DT><B>Returns:</B><DD>the original expression, rewritten to perform necessary run-time type checks,
 and to perform other type-related optimizations
<DT><B>Throws:</B>
<DD><CODE><A HREF="../../../net/sf/saxon/trans/XPathException.html" title="class in net.sf.saxon.trans">XPathException</A></CODE> - if an error is discovered during this phase
     (typically a type error)</DL>
</DD>
</DL>
<HR>

<A NAME="optimize(net.sf.saxon.expr.parser.ExpressionVisitor, net.sf.saxon.expr.parser.ExpressionVisitor.ContextItemType)"><!-- --></A><H3>
optimize</H3>
<PRE>
public <A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A> <B>optimize</B>(<A HREF="../../../net/sf/saxon/expr/parser/ExpressionVisitor.html" title="class in net.sf.saxon.expr.parser">ExpressionVisitor</A>&nbsp;visitor,
                           <A HREF="../../../net/sf/saxon/expr/parser/ExpressionVisitor.ContextItemType.html" title="class in net.sf.saxon.expr.parser">ExpressionVisitor.ContextItemType</A>&nbsp;contextItemType)
                    throws <A HREF="../../../net/sf/saxon/trans/XPathException.html" title="class in net.sf.saxon.trans">XPathException</A></PRE>
<DL>
<DD><B>Description copied from class: <CODE><A HREF="../../../net/sf/saxon/expr/Expression.html#optimize(net.sf.saxon.expr.parser.ExpressionVisitor, net.sf.saxon.expr.parser.ExpressionVisitor.ContextItemType)">Expression</A></CODE></B></DD>
<DD>Perform optimisation of an expression and its subexpressions. This is the third and final
 phase of static optimization.

 <p>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.</p>
<P>
<DD><DL>
<DT><B>Overrides:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/Expression.html#optimize(net.sf.saxon.expr.parser.ExpressionVisitor, net.sf.saxon.expr.parser.ExpressionVisitor.ContextItemType)">optimize</A></CODE> in class <CODE><A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>visitor</CODE> - an expression visitor<DD><CODE>contextItemType</CODE> - 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
 <A HREF="../../../net/sf/saxon/type/Type.html#ITEM_TYPE"><CODE>Type.ITEM_TYPE</CODE></A>
<DT><B>Returns:</B><DD>the original expression, rewritten if appropriate to optimize execution
<DT><B>Throws:</B>
<DD><CODE><A HREF="../../../net/sf/saxon/trans/XPathException.html" title="class in net.sf.saxon.trans">XPathException</A></CODE> - if an error is discovered during this phase
     (typically a type error)</DL>
</DD>
</DL>
<HR>

<A NAME="copy()"><!-- --></A><H3>
copy</H3>
<PRE>
public <A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A> <B>copy</B>()</PRE>
<DL>
<DD>Copy an expression. This makes a deep copy.
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/Expression.html#copy()">copy</A></CODE> in class <CODE><A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></CODE></DL>
</DD>
<DD><DL>

<DT><B>Returns:</B><DD>the copy of the original expression</DL>
</DD>
</DL>
<HR>

<A NAME="getItemType(net.sf.saxon.type.TypeHierarchy)"><!-- --></A><H3>
getItemType</H3>
<PRE>
public <A HREF="../../../net/sf/saxon/type/ItemType.html" title="interface in net.sf.saxon.type">ItemType</A> <B>getItemType</B>(<A HREF="../../../net/sf/saxon/type/TypeHierarchy.html" title="class in net.sf.saxon.type">TypeHierarchy</A>&nbsp;th)</PRE>
<DL>
<DD>Get the item type of the items returned by evaluating this instruction
<P>
<DD><DL>
<DT><B>Overrides:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#getItemType(net.sf.saxon.type.TypeHierarchy)">getItemType</A></CODE> in class <CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html" title="class in net.sf.saxon.expr.instruct">Instruction</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>th</CODE> - the type hierarchy cache
<DT><B>Returns:</B><DD>the static item type of the instruction</DL>
</DD>
</DL>
<HR>

<A NAME="promoteInst(net.sf.saxon.expr.parser.PromotionOffer)"><!-- --></A><H3>
promoteInst</H3>
<PRE>
protected void <B>promoteInst</B>(<A HREF="../../../net/sf/saxon/expr/parser/PromotionOffer.html" title="class in net.sf.saxon.expr.parser">PromotionOffer</A>&nbsp;offer)
                    throws <A HREF="../../../net/sf/saxon/trans/XPathException.html" title="class in net.sf.saxon.trans">XPathException</A></PRE>
<DL>
<DD>Handle promotion offers, that is, non-local tree rewrites.
<P>
<DD><DL>
<DT><B>Overrides:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#promoteInst(net.sf.saxon.expr.parser.PromotionOffer)">promoteInst</A></CODE> in class <CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html" title="class in net.sf.saxon.expr.instruct">Instruction</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>offer</CODE> - The type of rewrite being offered
<DT><B>Throws:</B>
<DD><CODE><A HREF="../../../net/sf/saxon/trans/XPathException.html" title="class in net.sf.saxon.trans">XPathException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="createsNewNodes()"><!-- --></A><H3>
createsNewNodes</H3>
<PRE>
public final boolean <B>createsNewNodes</B>()</PRE>
<DL>
<DD>Determine whether this instruction creates new nodes.
 This implementation returns true if the "action" creates new nodes.
 (Nodes created by the condition can't contribute to the result).
<P>
<DD><DL>
<DT><B>Overrides:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#createsNewNodes()">createsNewNodes</A></CODE> in class <CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html" title="class in net.sf.saxon.expr.instruct">Instruction</A></CODE></DL>
</DD>
<DD><DL>

<DT><B>Returns:</B><DD>true if the instruction creates new nodes (or if it can't be proved that it doesn't)</DL>
</DD>
</DL>
<HR>

<A NAME="iterateSubExpressions()"><!-- --></A><H3>
iterateSubExpressions</H3>
<PRE>
public <A HREF="http://download.oracle.com/javase/6/docs/api/java/util/Iterator.html?is-external=true" title="class or interface in java.util">Iterator</A>&lt;<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A>&gt; <B>iterateSubExpressions</B>()</PRE>
<DL>
<DD>Get all the XPath expressions associated with this instruction
 (in XSLT terms, the expression present on attributes of the instruction,
 as distinct from the child instructions in a sequence construction)
<P>
<DD><DL>
<DT><B>Overrides:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/Expression.html#iterateSubExpressions()">iterateSubExpressions</A></CODE> in class <CODE><A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></CODE></DL>
</DD>
<DD><DL>

<DT><B>Returns:</B><DD>an iterator containing the sub-expressions of this expression</DL>
</DD>
</DL>
<HR>

<A NAME="hasLoopingSubexpression(net.sf.saxon.expr.Expression)"><!-- --></A><H3>
hasLoopingSubexpression</H3>
<PRE>
public boolean <B>hasLoopingSubexpression</B>(<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A>&nbsp;child)</PRE>
<DL>
<DD>Given an expression that is an immediate child of this expression, test whether
 the evaluation of the parent expression causes the child expression to be
 evaluated repeatedly
<P>
<DD><DL>
<DT><B>Overrides:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/Expression.html#hasLoopingSubexpression(net.sf.saxon.expr.Expression)">hasLoopingSubexpression</A></CODE> in class <CODE><A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>child</CODE> - the immediate subexpression
<DT><B>Returns:</B><DD>true if the child expression is evaluated repeatedly</DL>
</DD>
</DL>
<HR>

<A NAME="replaceSubExpression(net.sf.saxon.expr.Expression, net.sf.saxon.expr.Expression)"><!-- --></A><H3>
replaceSubExpression</H3>
<PRE>
public boolean <B>replaceSubExpression</B>(<A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A>&nbsp;original,
                                    <A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A>&nbsp;replacement)</PRE>
<DL>
<DD>Replace one subexpression by a replacement subexpression
<P>
<DD><DL>
<DT><B>Overrides:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/Expression.html#replaceSubExpression(net.sf.saxon.expr.Expression, net.sf.saxon.expr.Expression)">replaceSubExpression</A></CODE> in class <CODE><A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>original</CODE> - the original subexpression<DD><CODE>replacement</CODE> - the replacement subexpression
<DT><B>Returns:</B><DD>true if the original subexpression is found</DL>
</DD>
</DL>
<HR>

<A NAME="processLeavingTail(net.sf.saxon.expr.XPathContext)"><!-- --></A><H3>
processLeavingTail</H3>
<PRE>
public <A HREF="../../../net/sf/saxon/expr/instruct/TailCall.html" title="interface in net.sf.saxon.expr.instruct">TailCall</A> <B>processLeavingTail</B>(<A HREF="../../../net/sf/saxon/expr/XPathContext.html" title="interface in net.sf.saxon.expr">XPathContext</A>&nbsp;context)
                            throws <A HREF="../../../net/sf/saxon/trans/XPathException.html" title="class in net.sf.saxon.trans">XPathException</A></PRE>
<DL>
<DD><B>Description copied from class: <CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#processLeavingTail(net.sf.saxon.expr.XPathContext)">Instruction</A></CODE></B></DD>
<DD>ProcessLeavingTail: 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.
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/instruct/TailCallReturner.html#processLeavingTail(net.sf.saxon.expr.XPathContext)">processLeavingTail</A></CODE> in interface <CODE><A HREF="../../../net/sf/saxon/expr/instruct/TailCallReturner.html" title="interface in net.sf.saxon.expr.instruct">TailCallReturner</A></CODE><DT><B>Specified by:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html#processLeavingTail(net.sf.saxon.expr.XPathContext)">processLeavingTail</A></CODE> in class <CODE><A HREF="../../../net/sf/saxon/expr/instruct/Instruction.html" title="class in net.sf.saxon.expr.instruct">Instruction</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>context</CODE> - The dynamic context of the transformation, giving access to the current node,
 the current variables, etc.
<DT><B>Returns:</B><DD>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.
<DT><B>Throws:</B>
<DD><CODE><A HREF="../../../net/sf/saxon/trans/XPathException.html" title="class in net.sf.saxon.trans">XPathException</A></CODE> - if a dynamic error occurs during the evaluation
 of the instruction</DL>
</DD>
</DL>
<HR>

<A NAME="explain(net.sf.saxon.trace.ExpressionPresenter)"><!-- --></A><H3>
explain</H3>
<PRE>
public void <B>explain</B>(<A HREF="../../../net/sf/saxon/trace/ExpressionPresenter.html" title="class in net.sf.saxon.trace">ExpressionPresenter</A>&nbsp;out)</PRE>
<DL>
<DD>Diagnostic print of expression structure. The abstract expression tree
 is written to the supplied output destination.
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../net/sf/saxon/expr/Expression.html#explain(net.sf.saxon.trace.ExpressionPresenter)">explain</A></CODE> in class <CODE><A HREF="../../../net/sf/saxon/expr/Expression.html" title="class in net.sf.saxon.expr">Expression</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>out</CODE> - the expression presenter used to display the structure</DL>
</DD>
</DL>
<!-- ========= END OF CLASS DATA ========= -->
<HR>


<!-- ======= START OF BOTTOM NAVBAR ====== -->
<A NAME="navbar_bottom"><!-- --></A>
<A HREF="#skip-navbar_bottom" title="Skip navigation links"></A>
<TABLE BORDER="0" WIDTH="100%" CELLPADDING="1" CELLSPACING="0" SUMMARY="">
<TR>
<TD COLSPAN=2 BGCOLOR="#EEEEFF" CLASS="NavBarCell1">
<A NAME="navbar_bottom_firstrow"><!-- --></A>
<TABLE BORDER="0" CELLPADDING="0" CELLSPACING="3" SUMMARY="">
  <TR ALIGN="center" VALIGN="top">
  <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1">    <A HREF="../../../overview-summary.html"><FONT CLASS="NavBarFont1"><B>Overview</B></FONT></A>&nbsp;</TD>
  <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1">    <A HREF="package-summary.html"><FONT CLASS="NavBarFont1"><B>Package</B></FONT></A>&nbsp;</TD>
  <TD BGCOLOR="#FFFFFF" CLASS="NavBarCell1Rev"> &nbsp;<FONT CLASS="NavBarFont1Rev"><B>Class</B></FONT>&nbsp;</TD>
  <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1">    <A HREF="package-tree.html"><FONT CLASS="NavBarFont1"><B>Tree</B></FONT></A>&nbsp;</TD>
  <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1">    <A HREF="../../../deprecated-list.html"><FONT CLASS="NavBarFont1"><B>Deprecated</B></FONT></A>&nbsp;</TD>
  <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1">    <A HREF="../../../index-all.html"><FONT CLASS="NavBarFont1"><B>Index</B></FONT></A>&nbsp;</TD>
  <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1">    <A HREF="../../../help-doc.html"><FONT CLASS="NavBarFont1"><B>Help</B></FONT></A>&nbsp;</TD>
  </TR>
</TABLE>
</TD>
<TD ALIGN="right" VALIGN="top" ROWSPAN=3><EM>
</EM>
</TD>
</TR>

<TR>
<TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2">
&nbsp;<A HREF="../../../com/saxonica/expr/TryCatch.CatchClause.html" title="class in com.saxonica.expr"><B>PREV CLASS</B></A>&nbsp;
&nbsp;<A HREF="../../../com/saxonica/expr/XPath30Parser.html" title="class in com.saxonica.expr"><B>NEXT CLASS</B></A></FONT></TD>
<TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2">
  <A HREF="../../../index.html?com/saxonica/expr/While.html" target="_top"><B>FRAMES</B></A>  &nbsp;
&nbsp;<A HREF="While.html" target="_top"><B>NO FRAMES</B></A>  &nbsp;
&nbsp;<SCRIPT type="text/javascript">
  <!--
  if(window==top) {
    document.writeln('<A HREF="../../../allclasses-noframe.html"><B>All Classes</B></A>');
  }
  //-->
</SCRIPT>
<NOSCRIPT>
  <A HREF="../../../allclasses-noframe.html"><B>All Classes</B></A>
</NOSCRIPT>


</FONT></TD>
</TR>
<TR>
<TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2">
  SUMMARY:&nbsp;NESTED&nbsp;|&nbsp;<A HREF="#fields_inherited_from_class_net.sf.saxon.expr.Expression">FIELD</A>&nbsp;|&nbsp;<A HREF="#constructor_summary">CONSTR</A>&nbsp;|&nbsp;<A HREF="#method_summary">METHOD</A></FONT></TD>
<TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2">
DETAIL:&nbsp;FIELD&nbsp;|&nbsp;<A HREF="#constructor_detail">CONSTR</A>&nbsp;|&nbsp;<A HREF="#method_detail">METHOD</A></FONT></TD>
</TR>
</TABLE>
<A NAME="skip-navbar_bottom"></A>
<!-- ======== END OF BOTTOM NAVBAR ======= -->

<HR>
Copyright (c) 2004-2011 Saxonica Limited. All rights reserved.
</BODY>
</HTML>