qscopeguard.qdoc

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// Copyright (C) 2018 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Sérgio Martins <sergio.martins@kdab.com>
// Copyright (C) 2019 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
 
#include "qscopeguard.h"
 
QT_BEGIN_NAMESPACE
 
/*!
    \class QScopeGuard
    \since 5.12
    \inmodule QtCore
    \brief Provides a scope guard for calling a function at the end of
           a scope.
 
    QScopeGuard<F> is a class of which the sole purpose is to run the function
    \a f in its destructor. This is useful for guaranteeing
    your cleanup code is executed, whether the function is exited normally,
    exited early by a return statement, or exited by an exception.
 
    \note Exceptions are not supported. The callable shouldn't throw when
          executed, copied or moved.
 
    \sa QScopedValueRollback
*/
 
/*!
    \fn template <typename F> QScopeGuard<F>::QScopeGuard(F &&f)
    \fn template <typename F> QScopeGuard<F>::QScopeGuard(const F &f)
 
    Create a scope guard that will execute \a f at the end of the scope.
 
    If \e F is a lambda, its type cannot be written. In that case you need to
    either rely on class template argument deduction (C++17 feature) and leave
    the template parameter out completely or use the helper function
    qScopeGuard() instead of this constructor.
 
    \since 5.15
*/
 
/*! \fn template <typename F> void QScopeGuard<F>::dismiss()
 
    Disarms the scope guard, so that the function \e F will not be called at
    the end of the scope.
*/
 
/*!
    \fn [qScopeGuard] template <typename F> QScopeGuard<typename std::decay<F>::type> qScopeGuard(F &&f)
    \inmodule QtCore
    \relates QScopeGuard
    \brief The qScopeGuard function can be used to call a function at the end
           of the scope.
    \ingroup misc
 
    Create a scope guard that will execute \a f at the end of the scope.
 
    This helper function is provided so that you can easily construct a
    QScopeGuard without having to name the template parameter for the type of
    the callable. If \e F is a lambda then you cannot write its type and relying
    on this helper or class template argument deduction is necessary.
 
    Example usage is as follows:
 
    \snippet code/src_corelib_tools_qscopeguard.cpp 0
 
*/
 
QT_END_NAMESPACE