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#ifndef QDECLARATIVEGUARD_P_H

#define QDECLARATIVEGUARD_P_H

//

//  W A R N I N G

//  -------------

//

// This file is not part of the Qt API.  It exists for the convenience

// of qapplication_*.cpp, qwidget*.cpp and qfiledialog.cpp.  This header

// file may change from version to version without notice, or even be removed.

//

// We mean it.

//

#include <QtCore/qglobal.h>

#include <QtCore/qvariant.h>

QT_BEGIN_NAMESPACE

class QObject;

template<class T>

class QDeclarativeGuard

{

    QObject *o;

    QDeclarativeGuard<QObject> *next;

    QDeclarativeGuard<QObject> **prev;

    friend class QDeclarativeData;

public:

    inline QDeclarativeGuard();

    inline QDeclarativeGuard(T *);

    inline QDeclarativeGuard(const QDeclarativeGuard<T> &);

    inline virtual ~QDeclarativeGuard();

    inline QDeclarativeGuard<T> &operator=(const QDeclarativeGuard<T> &o);

    inline QDeclarativeGuard<T> &operator=(T *);

    inline bool isNull() const

        { return !o; }

    inline T* operator->() const

        { return static_cast<T*>(const_cast<QObject*>(o)); }

    inline T& operator*() const

        { return *static_cast<T*>(const_cast<QObject*>(o)); }

    inline operator T*() const

        { return static_cast<T*>(const_cast<QObject*>(o)); }

    inline T* data() const

        { return static_cast<T*>(const_cast<QObject*>(o)); }

protected:

    virtual void objectDestroyed(T *) {}

private:

    inline void addGuard();

    inline void remGuard();

};

QT_END_NAMESPACE

Q_DECLARE_METATYPE(QDeclarativeGuard<QObject>)

#include "private/qdeclarativedata_p.h"

QT_BEGIN_NAMESPACE

template<class T>

QDeclarativeGuard<T>::QDeclarativeGuard()

: o(0), next(0), prev(0)

{

}

template<class T>

QDeclarativeGuard<T>::QDeclarativeGuard(T *g)

: o(g), next(0), prev(0)

{

    if (o) addGuard();

}

template<class T>

QDeclarativeGuard<T>::QDeclarativeGuard(const QDeclarativeGuard<T> &g)

: o(g.o), next(0), prev(0)

{

    if (o) addGuard();

}

template<class T>

QDeclarativeGuard<T>::~QDeclarativeGuard()

{

    if (prev) remGuard();

    o = 0;

}

template<class T>

QDeclarativeGuard<T> &QDeclarativeGuard<T>::operator=(const QDeclarativeGuard<T> &g)

{

    if (g.o != o) {

        if (prev) remGuard();

        o = g.o;

        if (o) addGuard();

    }

    return *this;

}

template<class T>

QDeclarativeGuard<T> &QDeclarativeGuard<T>::operator=(T *g)

{

    if (g != o) {

        if (prev) remGuard();

        o = g;

        if (o) addGuard();

    }

    return *this;

}

QT_END_NAMESPACE

#endif // QDECLARATIVEGUARD_P_H