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Provides a basic XSLT 2.0 and XQuery 1.0 processor (W3C Recommendations, January 2007). Command line interfaces and implementations of several Java APIs (DOM, XPath, s9api) are also included.
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package net.sf.saxon.instruct;
import net.sf.saxon.Configuration;
import net.sf.saxon.Controller;
import net.sf.saxon.query.XQueryFunctionLibrary;
import net.sf.saxon.query.XQueryFunction;
import net.sf.saxon.expr.*;
import net.sf.saxon.om.SingletonIterator;
import net.sf.saxon.om.UnfailingIterator;
import net.sf.saxon.om.ValueRepresentation;
import net.sf.saxon.trace.InstructionInfo;
import net.sf.saxon.trans.XPathException;

import java.util.ArrayList;
import java.util.List;
import java.util.Stack;

/**
* A compiled global variable in a stylesheet or query. 

*/

public class GlobalVariable extends GeneralVariable implements Container {

    private Executable executable;
    private SlotManager stackFrameMap = null;
    private int hostLanguage;

    /**
     * Create a global variable
     */

    public GlobalVariable(){}

    /**
     * Get the executable containing this global variable
     * @return the containing executable
     */

    public Executable getExecutable() {
        return executable;
    }

    /**
     * Set the containing executable
     * @param executable the executable that contains this global variable
     */

    public void setExecutable(Executable executable) {
        this.executable = executable;
    }

    /**
     * Set the host language for this declaration
     * @param language the host language (for example XSLT, XQuery)
     */

    public void setHostLanguage(int language) {
        hostLanguage = language;
    }

    /**
     * Get the host language for this declaration
     * @return the host language (for example XSLT, XQuery)
     */

    public int getHostLanguage() {
        return hostLanguage;
    }

    /**
     * The expression that initializes a global variable may itself use local variables.
     * In this case a stack frame needs to be allocated while evaluating the global variable
     * @param map The stack frame map for local variables used while evaluating this global
     * variable.
     */

    public void setContainsLocals(SlotManager map) {
        this.stackFrameMap = map;
    }

    /**
     * Is this a global variable?
     * @return true (yes, it is a global variable)
     */

    public boolean isGlobal() {
        return true;
    }

    /**
     * Check for cycles in this variable definition
     * @param referees the calls leading up to this one; it's an error if this variable is on the
     * stack, because that means it calls itself directly or indirectly. The stack may contain
     * variable definitions (GlobalVariable objects) and user-defined functions (UserFunction objects).
     * It will never contain the same object more than once.
     * @param globalFunctionLibrary the library containing all global functions
     */

    public void lookForCycles(Stack referees, XQueryFunctionLibrary globalFunctionLibrary) throws XPathException {
        if (referees.contains(this)) {
            int s = referees.indexOf(this);
            referees.push(this);
            String message = "Circular definition of global variable. $" +
                    getVariableQName().getDisplayName();
            for (int i = s; i < referees.size() - 1; i++) {
                if (i != s) {
                    message += ", which";
                }
                if (referees.get(i + 1) instanceof GlobalVariable) {
                    GlobalVariable next = (GlobalVariable)referees.get(i + 1);
                    message += " uses $" + next.getVariableQName().getDisplayName();
                } else if (referees.get(i + 1) instanceof XQueryFunction) {
                    XQueryFunction next = (XQueryFunction)referees.get(i + 1);
                    message += " calls " + next.getFunctionName().getDisplayName() +
                            "#" + next.getNumberOfArguments() + "()";
                }
            }
            message += '.';
            XPathException err = new XPathException(message);
            err.setErrorCode("XQST0054");
            err.setIsStaticError(true);
            err.setLocator(this);
            throw err;
        }
        if (select != null) {
            referees.push(this);
            List list = new ArrayList(10);
            ExpressionTool.gatherReferencedVariables(select, list);
            for (int i=0; i