1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <string_view> 11 12 // constexpr const_iterator begin() const; 13 14 #include <experimental/string_view> 15 #include <cassert> 16 17 template <class S> 18 void 19 test(S s) 20 { 21 const S& cs = s; 22 typename S::iterator b = s.begin(); 23 typename S::const_iterator cb1 = cs.begin(); 24 typename S::const_iterator cb2 = s.cbegin(); 25 if (!s.empty()) 26 { 27 assert( *b == s[0]); 28 assert( &*b == &s[0]); 29 assert( *cb1 == s[0]); 30 assert(&*cb1 == &s[0]); 31 assert( *cb2 == s[0]); 32 assert(&*cb2 == &s[0]); 33 34 } 35 assert( b == cb1); 36 assert( b == cb2); 37 assert(cb1 == cb2); 38 } 39 40 41 int main() 42 { 43 typedef std::experimental::string_view string_view; 44 typedef std::experimental::u16string_view u16string_view; 45 typedef std::experimental::u32string_view u32string_view; 46 typedef std::experimental::wstring_view wstring_view; 47 48 test(string_view ()); 49 test(u16string_view()); 50 test(u32string_view()); 51 test(wstring_view ()); 52 test(string_view ( "123")); 53 test(wstring_view (L"123")); 54 #if __cplusplus >= 201103L 55 test(u16string_view{u"123"}); 56 test(u32string_view{U"123"}); 57 #endif 58 59 #if _LIBCPP_STD_VER > 11 60 { 61 constexpr string_view sv { "123", 3 }; 62 constexpr u16string_view u16sv {u"123", 3 }; 63 constexpr u32string_view u32sv {U"123", 3 }; 64 constexpr wstring_view wsv {L"123", 3 }; 65 66 static_assert ( *sv.begin() == sv[0], "" ); 67 static_assert ( *u16sv.begin() == u16sv[0], "" ); 68 static_assert ( *u32sv.begin() == u32sv[0], "" ); 69 static_assert ( *wsv.begin() == wsv[0], "" ); 70 71 static_assert ( *sv.cbegin() == sv[0], "" ); 72 static_assert ( *u16sv.cbegin() == u16sv[0], "" ); 73 static_assert ( *u32sv.cbegin() == u32sv[0], "" ); 74 static_assert ( *wsv.cbegin() == wsv[0], "" ); 75 } 76 #endif 77 } 78
