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// Copyright (C) 2022 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
/*!
\headerfile <QtSwap>
\inmodule QtCore
\ingroup funclists
\brief Swapping the values of two variables.
*/
/*!
\fn template <typename T> void qSwap(T &lhs, T &rhs)
\relates <QtSwap>
Exchanges the values of variables \a lhs and \a rhs,
taking type-specific \c{swap()} overloads into account.
This function is Qt's version of
and is equivalent to
\code
using std::swap; // bring std::swap into scope (for built-in types)
swap(lhs, rhs); // unqualified call (picks up type-specific overloads
// via Argument-Dependent Lookup, or falls back to std::swap)
\endcode
Use this function primarily in generic code, where you would traditionally
have written the above two lines, because you don't know anything about \c{T}.
If you already know what \c{T} is, then use one of the following options, in
order of preference:
\list
\li \c{lhs.swap(rhs);} if such a member-swap exists
\li \c{std::swap(lhs, rhs);} if no type-specific \c{swap()} exists
\endlist
See
\l{https://www.boost.org/doc/libs/release/libs/core/doc/html/core/swap.html}{\c{boost::swap()} on boost.org}
for more details.
See also
*/