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 10 11 // UNSUPPORTED: GCC-ALWAYS_INLINE-FIXME 12 13 // <format> 14 15 // template<class T, class charT = char> 16 // requires same_as<remove_cvref_t<T>, T> && formattable<T, charT> 17 // class range_formatter 18 19 // constexpr formatter<T, charT>& underlying() noexcept; 20 // constexpr const formatter<T, charT>& underlying() const noexcept; 21 22 #include <concepts> 23 #include <format> 24 25 #include "test_macros.h" 26 27 template <class CharT> 28 constexpr void test_underlying() { 29 { 30 std::range_formatter<int, CharT> formatter; 31 [[maybe_unused]] std::same_as<std::formatter<int, CharT>&> decltype(auto) underlying = formatter.underlying(); 32 static_assert(noexcept(formatter.underlying())); 33 } 34 { 35 const std::range_formatter<int, CharT> formatter; 36 [[maybe_unused]] std::same_as<const std::formatter<int, CharT>&> decltype(auto) underlying = formatter.underlying(); 37 static_assert(noexcept(formatter.underlying())); 38 } 39 } 40 41 constexpr bool test() { 42 test_underlying<char>(); 43 #ifndef TEST_HAS_NO_WIDE_CHARACTERS 44 test_underlying<wchar_t>(); 45 #endif 46 47 return true; 48 } 49 50 int main(int, char**) { 51 test(); 52 static_assert(test()); 53 54 return 0; 55 } 56