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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
49#if QT_HAS_CPP_ATTRIBUTE(nodiscard) && __cplusplus >= 201703L
50[[nodiscard]]
51#endif
52QScopedValueRollback
53{
54public:
55 explicit QScopedValueRollback(T &var)
56 : varRef(var), oldValue(var)
57 {
58 }
59
60 explicit QScopedValueRollback(T &var, T value)
61 : varRef(var), oldValue(std::move(var))
62 {
63 varRef = std::move(value);
64 }
65
66 ~QScopedValueRollback()
67 {
68 varRef = std::move(oldValue);
69 }
70
71 void commit()
72 {
73 oldValue = varRef;
74 }
75
76private:
77 T &varRef;
78 T oldValue;
79
80 Q_DISABLE_COPY(QScopedValueRollback)
81};
82
83QT_END_NAMESPACE
84
85#endif // QSCOPEDVALUEROLLBACK_H
86