/****************************************************************************
**
** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
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** This file is part of the QtXmlPatterns module of the Qt Toolkit.
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** $QT_BEGIN_LICENSE:LGPL21$
** Commercial License Usage
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** accordance with the commercial license agreement provided with the
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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_UnresolvedVariableReference_H
#define Patternist_UnresolvedVariableReference_H

#include <private/qemptycontainer_p.h>

QT_BEGIN_NAMESPACE

namespace QPatternist
{

    /**
     * @short Compile time only AST-node which is a marker for variable
     * references whose declaration has not yet appeared in the source code.
     *
     * This can not appear in XQuery, but can in XSL-T.
     *
     * @author Frans Englich <frans.englich@nokia.com>
     * @ingroup Patternist_expressions
     * @since 4.5
     */
    class Q_AUTOTEST_EXPORT UnresolvedVariableReference : public EmptyContainer
    {
    public:
        UnresolvedVariableReference(const QXmlName &name);

        virtual Expression::Ptr typeCheck(const StaticContext::Ptr &context,
                                          const SequenceType::Ptr &reqType);
        virtual SequenceType::List expectedOperandTypes() const;
        virtual SequenceType::Ptr staticType() const;
        virtual ExpressionVisitorResult::Ptr accept(const ExpressionVisitor::Ptr &visitor) const;
        virtual ID id() const;

        inline void bindTo(const Expression::Ptr &body);

        inline Expression::Ptr replacement() const;

    private:
        const QXmlName  m_name;
        Expression::Ptr m_replacement;
    };

    void UnresolvedVariableReference::bindTo(const Expression::Ptr &body)
    {
        Q_ASSERT(body);
        m_replacement = body;
    }

    Expression::Ptr UnresolvedVariableReference::replacement() const
    {
        Q_ASSERT(m_replacement);
        return m_replacement;
    }

}

QT_END_NAMESPACE

#endif
