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 // NOTE: Older versions of clang have a bug where they fail to evaluate 11 // string_view::at as a constant expression. 12 // XFAIL: clang-3.4, clang-3.3 13 14 15 // <string_view> 16 17 // constexpr const _CharT& at(size_type _pos) const; 18 19 #include <string_view> 20 #include <stdexcept> 21 #include <cassert> 22 23 #include "test_macros.h" 24 25 template <typename CharT> 26 void test ( const CharT *s, size_t len ) { 27 std::basic_string_view<CharT> sv ( s, len ); 28 assert ( sv.length() == len ); 29 for ( size_t i = 0; i < len; ++i ) { 30 assert ( sv.at(i) == s[i] ); 31 assert ( &sv.at(i) == s + i ); 32 } 33 34 #ifndef TEST_HAS_NO_EXCEPTIONS 35 try { (void)sv.at(len); } catch ( const std::out_of_range & ) { return ; } 36 assert ( false ); 37 #endif 38 } 39 40 int main () { 41 test ( "ABCDE", 5 ); 42 test ( "a", 1 ); 43 44 test ( L"ABCDE", 5 ); 45 test ( L"a", 1 ); 46 47 #if TEST_STD_VER >= 11 48 test ( u"ABCDE", 5 ); 49 test ( u"a", 1 ); 50 51 test ( U"ABCDE", 5 ); 52 test ( U"a", 1 ); 53 #endif 54 55 #if TEST_STD_VER >= 11 56 { 57 constexpr std::basic_string_view<char> sv ( "ABC", 2 ); 58 static_assert ( sv.length() == 2, "" ); 59 static_assert ( sv.at(0) == 'A', "" ); 60 static_assert ( sv.at(1) == 'B', "" ); 61 } 62 #endif 63 } 64
