source: trunk/src/xmlpatterns/expr/qvariabledeclaration_p.h@ 561

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//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.

#ifndef Patternist_VariableDeclaration_H
#define Patternist_VariableDeclaration_H

#include <QSharedData>

#include "qexpression_p.h"
#include "qpatternistlocale_p.h"
#include "qvariablereference_p.h"

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

template<typename T> class QStack;

namespace QPatternist
{
    /**
     * @short Represents a declared variable. Only used at
     * the compilation stage.
     *
     * @see FunctionArgument
     * @author Frans Englich <[email protected]>
     * @ingroup Patternist_expressions
     */
    class VariableDeclaration : public QSharedData
    {
    public:
        typedef QExplicitlySharedDataPointer<VariableDeclaration> Ptr;
        typedef QStack<VariableDeclaration::Ptr> Stack;
        typedef QList<VariableDeclaration::Ptr> List;

        /**
         * @short The key is the variable name.
         */
        typedef QHash<QXmlName, VariableDeclaration::Ptr> Hash;

        enum Type
        {
            RangeVariable,
            ExpressionVariable,
            FunctionArgument,
            PositionalVariable,
            TemplateParameter,

            /**
             * A global variable is always an external variable, but it is
             * cached differently.
             *
             * @see DynamicContext::globalItemCacheCell()
             */
            GlobalVariable,

            /**
             * External variables doesn't use slots, that's a big difference
             * compared to the other types.
             */
            ExternalVariable
        };

        /**
         * Creates a VariableDeclaration.
         *
         * @p sourceExpr and @p seqType may be @c null.
         */
        VariableDeclaration(const QXmlName n,
                            const VariableSlotID varSlot,
                            const Type t,
                            const SequenceType::Ptr &seqType) : name(n)
                                                              , slot(varSlot)
                                                              , type(t)
                                                              , sequenceType(seqType)
                                                              , canSourceRewrite(true)
        {
            Q_ASSERT(!name.isNull());
            Q_ASSERT(t == ExternalVariable || t == TemplateParameter || varSlot > -1);