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39
40#ifndef QSCOPEDVALUEROLLBACK_H
41#define QSCOPEDVALUEROLLBACK_H
42
43#include <QtCore/qglobal.h>
44
45QT_BEGIN_NAMESPACE
46
47template <typename T>
48class QScopedValueRollback
49{
50public:
51 explicit QScopedValueRollback(T &var)
52 : varRef(var), oldValue(var)
53 {
54 }
55
56 explicit QScopedValueRollback(T &var, T value)
57 : varRef(var), oldValue(std::move(var))
58 {
59 varRef = std::move(value);
60 }
61
62 ~QScopedValueRollback()
63 {
64 varRef = std::move(oldValue);
65 }
66
67 void commit()
68 {
69 oldValue = varRef;
70 }
71
72private:
73 T &varRef;
74 T oldValue;
75
76 Q_DISABLE_COPY(QScopedValueRollback)
77};
78
79QT_END_NAMESPACE
80
81#endif // QSCOPEDVALUEROLLBACK_H
82