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 11 // <string_view> 12 13 // constexpr basic_string_view substr(size_type pos = 0, size_type n = npos) const; 14 15 // Throws: out_of_range if pos > size(). 16 // Effects: Determines the effective length rlen of the string to reference as the smaller of n and size() - pos. 17 // Returns: basic_string_view(data()+pos, rlen). 18 19 #include <experimental/string_view> 20 #include <cassert> 21 22 template<typename CharT> 23 void test1 ( std::experimental::basic_string_view<CharT> sv, size_t n, size_t pos ) { 24 try { 25 std::experimental::basic_string_view<CharT> sv1 = sv.substr(pos, n); 26 const size_t rlen = std::min ( n, sv.size() - pos ); 27 assert ( sv1.size() == rlen ); 28 for ( size_t i = 0; i <= rlen; ++i ) 29 assert ( sv[pos+i] == sv1[i] ); 30 } 31 catch ( const std::out_of_range & ) { assert ( pos > sv.size()); } 32 } 33 34 35 template<typename CharT> 36 void test ( const CharT *s ) { 37 typedef std::experimental::basic_string_view<CharT> string_view_t; 38 39 string_view_t sv1 ( s ); 40 41 test1(sv1, 0, 0); 42 test1(sv1, 1, 0); 43 test1(sv1, 20, 0); 44 test1(sv1, sv1.size(), 0); 45 46 test1(sv1, 0, 3); 47 test1(sv1, 2, 3); 48 test1(sv1, 100, 3); 49 50 test1(sv1, 0, string_view_t::npos); 51 test1(sv1, 2, string_view_t::npos); 52 test1(sv1, sv1.size(), string_view_t::npos); 53 54 test1(sv1, sv1.size() + 1, 0); 55 test1(sv1, sv1.size() + 1, 1); 56 test1(sv1, sv1.size() + 1, string_view_t::npos); 57 } 58 59 int main () { 60 test ( "ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" ); 61 test ( "ABCDE"); 62 test ( "a" ); 63 test ( "" ); 64 65 test ( L"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" ); 66 test ( L"ABCDE" ); 67 test ( L"a" ); 68 test ( L"" ); 69 70 #if __cplusplus >= 201103L 71 test ( u"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" ); 72 test ( u"ABCDE" ); 73 test ( u"a" ); 74 test ( u"" ); 75 76 test ( U"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" ); 77 test ( U"ABCDE" ); 78 test ( U"a" ); 79 test ( U"" ); 80 #endif 81 82 #if _LIBCPP_STD_VER > 11 83 { 84 constexpr std::experimental::string_view sv1 { "ABCDE", 5 }; 85 86 { 87 constexpr std::experimental::string_view sv2 = sv1.substr ( 0, 3 ); 88 static_assert ( sv2.size() == 3, "" ); 89 static_assert ( sv2[0] == 'A', "" ); 90 static_assert ( sv2[1] == 'B', "" ); 91 static_assert ( sv2[2] == 'C', "" ); 92 } 93 94 { 95 constexpr std::experimental::string_view sv2 = sv1.substr ( 3, 0 ); 96 static_assert ( sv2.size() == 0, "" ); 97 } 98 99 { 100 constexpr std::experimental::string_view sv2 = sv1.substr ( 3, 3 ); 101 static_assert ( sv2.size() == 2, "" ); 102 static_assert ( sv2[0] == 'D', "" ); 103 static_assert ( sv2[1] == 'E', "" ); 104 } 105 } 106 #endif 107 } 108
