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// Copyright (C) 2022 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
/*!
\macro Q_DISABLE_COPY(Class)
\relates <QtClassHelperMacros>
Disables the use of copy constructors and assignment operators
for the given \a Class.
Instances of subclasses of QObject should not be thought of as
values that can be copied or assigned, but as unique identities.
This means that when you create your own subclass of QObject
(director or indirect), you should \e not give it a copy constructor
or an assignment operator. However, it may not enough to simply
omit them from your class, because, if you mistakenly write some code
that requires a copy constructor or an assignment operator (it's easy
to do), your compiler will thoughtfully create it for you. You must
do more.
The curious user will have seen that the Qt classes derived
from QObject typically include this macro in a private section:
\snippet code/src_corelib_global_qglobal.cpp 43
It declares a copy constructor and an assignment operator in the
private section, so that if you use them by mistake, the compiler
will report an error.
\snippet code/src_corelib_global_qglobal.cpp 44
But even this might not catch absolutely every case. You might be
tempted to do something like this:
\snippet code/src_corelib_global_qglobal.cpp 45
First of all, don't do that. Most compilers will generate code that
uses the copy constructor, so the privacy violation error will be
reported, but your C++ compiler is not required to generate code for
this statement in a specific way. It could generate code using
\e{neither} the copy constructor \e{nor} the assignment operator we
made private. In that case, no error would be reported, but your
application would probably crash when you called a member function
of \c{w}.
\sa Q_DISABLE_COPY_MOVE
*/
/*!
\macro Q_DISABLE_COPY_MOVE(Class)
\relates <QtClassHelperMacros>
A convenience macro that disables the use of copy constructors, assignment
operators, move constructors and move assignment operators for the given
\a Class.
\sa Q_DISABLE_COPY
\since 5.13
*/
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