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
test_constexpr()22 constexpr bool test_constexpr() {
23   return std::char_traits<char>::length("") == 0 && std::char_traits<char>::length("abcd") == 4;
24 }
25 #endif
26 
main(int,char **)27 int 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