42 lines · cpp
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-exception6//7//===----------------------------------------------------------------------===//8 9// <string>10 11// template<> struct char_traits<char16_t>12 13// static size_t length(const char_type* s);14// constexpr in C++1715 16#include <string>17#include <cassert>18 19#include "test_macros.h"20 21#if TEST_STD_VER > 1422constexpr bool test_constexpr() {23 return std::char_traits<char16_t>::length(u"") == 0 && std::char_traits<char16_t>::length(u"abcd") == 4;24}25#endif26 27int main(int, char**) {28#if TEST_STD_VER >= 1129 assert(std::char_traits<char16_t>::length(u"") == 0);30 assert(std::char_traits<char16_t>::length(u"a") == 1);31 assert(std::char_traits<char16_t>::length(u"aa") == 2);32 assert(std::char_traits<char16_t>::length(u"aaa") == 3);33 assert(std::char_traits<char16_t>::length(u"aaaa") == 4);34#endif35 36#if TEST_STD_VER > 1437 static_assert(test_constexpr(), "");38#endif39 40 return 0;41}42