xref: /llvm-project/libcxx/test/libcxx/ranges/range.adaptors/range.adaptor.helpers/as-lvalue.pass.cpp (revision dfddc0c4843baaf9605aeb1c4f82eac185e90265)
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
10 
11 // template<class T>
12 // constexpr T& as-lvalue(T&& t) { // exposition only
13 
14 #include <__utility/as_lvalue.h>
15 #include <type_traits>
16 #include <utility>
17 
18 constexpr bool test() {
19   // Check glvalue
20   {
21     int lvalue{};
22     [[maybe_unused]] decltype(auto) check = std::__as_lvalue(lvalue);
23     static_assert(std::is_same<decltype(check), int&>::value, "");
24   }
25 
26   // Check xvalue
27   {
28     int xvalue{};
29     [[maybe_unused]] decltype(auto) check = std::__as_lvalue(std::move(xvalue));
30     static_assert(std::is_same<decltype(check), int&>::value, "");
31   }
32 
33   return true;
34 }
35 
36 int main(int, char**) {
37   test();
38   static_assert(test(), "");
39 
40   return 0;
41 }
42