1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // UNSUPPORTED: c++03, c++11, c++14, c++17
10 // UNSUPPORTED: libcpp-no-concepts
11 
12 // template<class I1, class I2>
13 // concept indirectly_swappable;
14 
15 #include <iterator>
16 
17 #include <concepts>
18 
19 template<class I1, class I2>
20   requires std::indirectly_readable<I1> && std::indirectly_readable<I2>
21 constexpr bool indirectly_swappable_subsumption() {
22   return false;
23 }
24 
25 template<class I1, class I2>
26   requires std::indirectly_swappable<I1, I2>
27 constexpr bool indirectly_swappable_subsumption() {
28   return true;
29 }
30 
31 static_assert(indirectly_swappable_subsumption<int*, int*>());
32