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, c++20, c++23
10 
11 // <charconv>
12 
13 // struct from_chars_result
14 //   constexpr explicit operator bool() const noexcept { return ec == errc{}; }
15 
16 #include <charconv>
17 
18 #include <cassert>
19 #include <system_error>
20 #include <type_traits>
21 
22 #include "test_macros.h"
23 
24 static_assert(!std::is_convertible_v<std::from_chars_result, bool>);
25 static_assert(std::is_constructible_v<bool, std::from_chars_result>);
26 
27 constexpr bool test() {
28   // True
29   {
30     std::from_chars_result value{nullptr, std::errc{}};
31     assert(bool(value) == true);
32     static_assert(noexcept(bool(value)) == true);
33   }
34   // False
35   {
36     std::from_chars_result value{nullptr, std::errc::value_too_large};
37     assert(bool(value) == false);
38     static_assert(noexcept(bool(value)) == true);
39   }
40 
41   return true;
42 }
43 
44 int main(int, char**) {
45   assert(test());
46   static_assert(test());
47 
48   return 0;
49 }
50