/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
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** Contact: Nokia Corporation (qt-info@nokia.com)
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** This file is part of the QtXmlPatterns module of the Qt Toolkit.
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** No Commercial Usage
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** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
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** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
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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_PositionVariableReference_H
#define Patternist_PositionVariableReference_H

#include "qvariablereference_p.h"

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

namespace QPatternist
{
    /**
     * @short A reference to an @c at variable, declared with the
     * <tt>for</tt>-part in XQuery's FLWOR expression.
     *
     * @author Frans Englich <frans.englich@nokia.com>
     * @ingroup Patternist_expressions
     */
    class PositionalVariableReference : public VariableReference
    {
    public:
        typedef QExplicitlySharedDataPointer<PositionalVariableReference> Ptr;
        PositionalVariableReference(const VariableSlotID slot);

        virtual Item evaluateSingleton(const DynamicContext::Ptr &context) const;

        /**
         * Returns always @c true, since a positional variable is always one or more, and the
         * Effective %Boolean Value for that range is always @c true.
         *
         * @returns always @c true
         */
        virtual bool evaluateEBV(const DynamicContext::Ptr &context) const;

        /**
         * @returns always CommonSequenceTypes::ExactlyOneInteger
         */
        virtual SequenceType::Ptr staticType() const;

        virtual ExpressionVisitorResult::Ptr accept(const ExpressionVisitor::Ptr &visitor) const;
        virtual Properties properties() const;
    };
}

QT_END_NAMESPACE

QT_END_HEADER

#endif
