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// <string>
10
11// template<> struct char_traits<char>
12
13// static size_t length(const char_type* s);
14// constexpr in C++17
15
16#include <string>
17#include <cassert>
18
19#include "test_macros.h"
20
21#if TEST_STD_VER > 14
22constexpr bool test_constexpr() {
23 return std::char_traits<char>::length("") == 0 && std::char_traits<char>::length("abcd") == 4;
24}
25#endif
26
27int main(int, char**) {
28 assert(std::char_traits<char>::length("") == 0);
29 assert(std::char_traits<char>::length("a") == 1);
30 assert(std::char_traits<char>::length("aa") == 2);
31 assert(std::char_traits<char>::length("aaa") == 3);
32 assert(std::char_traits<char>::length("aaaa") == 4);
33
34#if TEST_STD_VER > 14
35 static_assert(test_constexpr(), "");
36#endif
37
38 return 0;
39}
40

source code of libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/length.pass.cpp