61 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// UNSUPPORTED: !stdlib=libc++ && (c++03 || c++11 || c++14)10 11// <string_view>12 13// constexpr const _CharT& operator[](size_type _pos) const;14 15#include <string_view>16#include <cassert>17 18#include "test_macros.h"19 20template <typename CharT>21void test(const CharT* s, std::size_t len) {22 typedef std::basic_string_view<CharT> SV;23 SV sv(s, len);24 ASSERT_SAME_TYPE(decltype(sv[0]), typename SV::const_reference);25 LIBCPP_ASSERT_NOEXCEPT(sv[0]);26 assert(sv.length() == len);27 for (std::size_t i = 0; i < len; ++i) {28 assert(sv[i] == s[i]);29 assert(&sv[i] == s + i);30 }31}32 33int main(int, char**) {34 test("ABCDE", 5);35 test("a", 1);36 37#ifndef TEST_HAS_NO_WIDE_CHARACTERS38 test(L"ABCDE", 5);39 test(L"a", 1);40#endif41 42#if TEST_STD_VER >= 1143 test(u"ABCDE", 5);44 test(u"a", 1);45 46 test(U"ABCDE", 5);47 test(U"a", 1);48#endif49 50#if TEST_STD_VER > 1151 {52 constexpr std::basic_string_view<char> sv("ABC", 2);53 static_assert(sv.length() == 2, "");54 static_assert(sv[0] == 'A', "");55 static_assert(sv[1] == 'B', "");56 }57#endif58 59 return 0;60}61