|  | // { dg-do compile { target c++20 } } | 
|  | // | 
|  | // Copyright (C) 2019-2025 Free Software Foundation, Inc. | 
|  | // | 
|  | // This file is part of the GNU ISO C++ Library.  This library is free | 
|  | // software; you can redistribute it and/or modify it under the | 
|  | // terms of the GNU General Public License as published by the | 
|  | // Free Software Foundation; either version 3, or (at your option) | 
|  | // any later version. | 
|  | // | 
|  | // This library is distributed in the hope that it will be useful, | 
|  | // but WITHOUT ANY WARRANTY; without even the implied warranty of | 
|  | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | 
|  | // GNU General Public License for more details. | 
|  | // | 
|  | // You should have received a copy of the GNU General Public License along | 
|  | // with this library; see the file COPYING3.  If not see | 
|  | // <http://www.gnu.org/licenses/>. | 
|  |  | 
|  | #include <tuple> | 
|  |  | 
|  | constexpr bool | 
|  | test_tuple() | 
|  | { | 
|  | auto ok = true; | 
|  |  | 
|  | std::tuple<int, double, double> t1(1, 3.1415, 2.7182); | 
|  | std::tuple<int, double, double> t2(1, 4.1234, 3.3333); | 
|  | t1.swap(t2); | 
|  | std::swap(t1, t2); | 
|  |  | 
|  | return ok; | 
|  | } | 
|  |  | 
|  | static_assert(test_tuple()); |