diff options
Diffstat (limited to 'src/corelib/global/qswap.qdoc')
| -rw-r--r-- | src/corelib/global/qswap.qdoc | 36 |
1 files changed, 30 insertions, 6 deletions
diff --git a/src/corelib/global/qswap.qdoc b/src/corelib/global/qswap.qdoc index 2d9d56b694..bffad903f9 100644 --- a/src/corelib/global/qswap.qdoc +++ b/src/corelib/global/qswap.qdoc @@ -1,14 +1,38 @@ // Copyright (C) 2022 The Qt Company Ltd. // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only -/*! \fn template <typename T> void qSwap(T &var1, T &var2) +/*! + \fn template <typename T> void qSwap(T &lhs, T &rhs) \relates <QtSwap> - \deprecated - Use \c std::swap instead. + Exchanges the values of variables \a lhs and \a rhs, + taking type-specific \c{swap()} overloads into account. - Exchanges the values of variables \a var1 and \a var2. + This function is Qt's version of + \l{https://www.boost.org/doc/libs/release/libs/core/doc/html/core/swap.html}{\c{boost::swap()}}, + 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 - Example: - \snippet code/doc_src_qalgorithms.cpp 0 + 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 + \l{https://en.cppreference.com/w/cpp/algorithm/swap}{\c{std::swap} on cppreference.com}, + \l{https://en.cppreference.com/w/cpp/named_req/Swappable}{\c{Swappable} on cppreference.com}. */ |