/****************************************************************************
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** Copyright (C) 2015 The Qt Company Ltd.
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** This file is part of the QtXmlPatterns module of the Qt Toolkit.
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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_ParentNodeAxis_H
#define Patternist_ParentNodeAxis_H

#include <private/qemptycontainer_p.h>

QT_BEGIN_NAMESPACE

namespace QPatternist
{
    /**
     * @short Corresponds to the expression <tt>parent::node()</tt>.
     *
     * This AST node is now useless, due to refactorings. Prevously we had
     * Item QAbstractXmlNodeModel::parent(), which didn't have the overhead of
     * allocating an iterator for a single node. However, in order to stream
     * line the API it is now gone and hence the node performs exactly the same
     * as AxisStep.
     *
     * @author Frans Englich <frans.englich@nokia.com>
     * @ingroup Patternist_expressions
     */
    class ParentNodeAxis : public EmptyContainer
    {
    public:
        virtual Item evaluateSingleton(const DynamicContext::Ptr &context) const;

        /**
         * @returns always DisableElimination
         */
        virtual Expression::Properties properties() const;

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

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

        /**
         * @returns always BuiltinTypes::node;
         */
        virtual ItemType::Ptr expectedContextItemType() const;
    };
}

QT_END_NAMESPACE

#endif
