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_view> 10 11 // const_iterator rbegin() const; 12 13 #include <string_view> 14 #include <cassert> 15 16 #include "test_macros.h" 17 18 template <class S> 19 void 20 test(S s) 21 { 22 const S& cs = s; 23 typename S::reverse_iterator b = s.rbegin(); 24 typename S::const_reverse_iterator cb1 = cs.rbegin(); 25 typename S::const_reverse_iterator cb2 = s.crbegin(); 26 if (!s.empty()) 27 { 28 const size_t last = s.size() - 1; 29 assert( *b == s[last]); 30 assert( &*b == &s[last]); 31 assert( *cb1 == s[last]); 32 assert(&*cb1 == &s[last]); 33 assert( *cb2 == s[last]); 34 assert(&*cb2 == &s[last]); 35 36 } 37 assert( b == cb1); 38 assert( b == cb2); 39 assert(cb1 == cb2); 40 } 41 42 43 int main(int, char**) 44 { 45 typedef std::string_view string_view; 46 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 47 typedef std::u8string_view u8string_view; 48 #endif 49 typedef std::u16string_view u16string_view; 50 typedef std::u32string_view u32string_view; 51 typedef std::wstring_view wstring_view; 52 53 test(string_view ()); 54 test(u16string_view()); 55 test(u32string_view()); 56 test(wstring_view ()); 57 test(string_view ( "123")); 58 test(wstring_view (L"123")); 59 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 60 test(u8string_view{u8"123"}); 61 #endif 62 #if TEST_STD_VER >= 11 63 test(u16string_view{u"123"}); 64 test(u32string_view{U"123"}); 65 #endif 66 67 #if TEST_STD_VER > 14 68 { 69 constexpr string_view sv { "123", 3 }; 70 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 71 constexpr u8string_view u8sv {u8"123", 3 }; 72 #endif 73 constexpr u16string_view u16sv {u"123", 3 }; 74 constexpr u32string_view u32sv {U"123", 3 }; 75 constexpr wstring_view wsv {L"123", 3 }; 76 77 static_assert ( *sv.rbegin() == sv[2], "" ); 78 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 79 static_assert ( *u8sv.rbegin() == u8sv[2], "" ); 80 #endif 81 static_assert ( *u16sv.rbegin() == u16sv[2], "" ); 82 static_assert ( *u32sv.rbegin() == u32sv[2], "" ); 83 static_assert ( *wsv.rbegin() == wsv[2], "" ); 84 85 static_assert ( *sv.crbegin() == sv[2], "" ); 86 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 87 static_assert ( *u8sv.crbegin() == u8sv[2], "" ); 88 #endif 89 static_assert ( *u16sv.crbegin() == u16sv[2], "" ); 90 static_assert ( *u32sv.crbegin() == u32sv[2], "" ); 91 static_assert ( *wsv.crbegin() == wsv[2], "" ); 92 } 93 #endif 94 95 return 0; 96 } 97