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/****************************************************************************
**
** Copyright (C) 2022 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:COMM$
**
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** $QT_END_LICENSE$
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
**
******************************************************************************/
#ifndef QSCOPEDVALUEROLLBACK_H
#define QSCOPEDVALUEROLLBACK_H
#include <QtCore/qglobal.h>
QT_BEGIN_NAMESPACE
template <typename T>
class [[nodiscard]] QScopedValueRollback
{
public:
explicit constexpr QScopedValueRollback(T &var)
: varRef(var), oldValue(var)
{
}
explicit constexpr QScopedValueRollback(T &var, T value)
: varRef(var), oldValue(qExchange(var, std::move(value)))
{
}
#if __cpp_constexpr >= 201907L
constexpr
#endif
~QScopedValueRollback()
{
varRef = std::move(oldValue);
}
constexpr void commit()
{
oldValue = varRef;
}
private:
T &varRef;
T oldValue;
Q_DISABLE_COPY(QScopedValueRollback)
};
QT_END_NAMESPACE
#endif // QSCOPEDVALUEROLLBACK_H
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