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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_DECLARE_TYPEINFO(Type, Flags)
\relates <QTypeInfo>
You can use this macro to specify information about a custom type
\a Type. With accurate type information, Qt's \l{Container Classes}
{generic containers} can choose appropriate storage methods and
algorithms.
\a Flags can be one of the following:
\list
\li \c Q_PRIMITIVE_TYPE specifies that \a Type requires no
operation to be performed in order to be properly destroyed,
and that it is possible to use memcpy() in order to create a
valid independent copy of an object.
\li \c Q_RELOCATABLE_TYPE specifies that \a Type has a constructor
and/or a destructor, but it can still be \e{relocated} in memory
by using \c memcpy().
\li \c Q_MOVABLE_TYPE is the same as \c Q_RELOCATABLE_TYPE. Prefer to use
\c Q_RELOCATABLE_TYPE in new code. Note: despite the name, this
has nothing to do with move constructors or C++ move semantics.
\li \c Q_COMPLEX_TYPE (the default) specifies that \a Type has
constructors and/or a destructor and that it may not be moved
in memory.
\endlist
Example of a "primitive" type:
\snippet code/src_corelib_global_qglobal.cpp 38
An example of a non-POD "primitive" type is QUuid: Even though
QUuid has constructors (and therefore isn't POD), every bit
pattern still represents a valid object, and memcpy() can be used
to create a valid independent copy of a QUuid object.
Example of a relocatable type:
\snippet code/src_corelib_global_qglobal.cpp 39
Qt will try to detect the class of a type using standard C++ type traits;
use this macro to tune the behavior.
For instance many types would be candidates for Q_RELOCATABLE_TYPE despite
not being trivially-copyable.
*/
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