qscopedvaluerollback.h

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#ifndef QSCOPEDVALUEROLLBACK_H
#define QSCOPEDVALUEROLLBACK_H

#include <QtCore/qglobal.h>

QT_BEGIN_HEADER
QT_BEGIN_NAMESPACE
QT_MODULE(Core)

template <typename T>
class QScopedValueRollback
{
public:
    QScopedValueRollback(T &var) :
        varRef(var)
    {
        oldValue = varRef;
    }

    ~QScopedValueRollback()
    {
        varRef = oldValue;
    }

    void commit()
    {
        oldValue = varRef;
    }

private:
    T& varRef;
    T oldValue;

    Q_DISABLE_COPY(QScopedValueRollback)
};

QT_END_NAMESPACE
QT_END_HEADER

#endif // QSCOPEDVALUEROLLBACK_H