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 // <iterator> 11 12 // All of these became constexpr in C++17 13 // 14 // template <InputIterator Iter> 15 // constexpr void advance(Iter& i, Iter::difference_type n); 16 // 17 // template <BidirectionalIterator Iter> 18 // constexpr void advance(Iter& i, Iter::difference_type n); 19 // 20 // template <RandomAccessIterator Iter> 21 // constexpr void advance(Iter& i, Iter::difference_type n); 22 23 #include <iterator> 24 #include <cassert> 25 26 #include "test_iterators.h" 27 28 template <class It> 29 void 30 test(It i, typename std::iterator_traits<It>::difference_type n, It x) 31 { 32 std::advance(i, n); 33 assert(i == x); 34 } 35 36 #if TEST_STD_VER > 14 37 template <class It> 38 constexpr bool 39 constepxr_test(It i, typename std::iterator_traits<It>::difference_type n, It x) 40 { 41 std::advance(i, n); 42 return i == x; 43 } 44 #endif 45 46 int main() 47 { 48 { 49 const char* s = "1234567890"; 50 test(input_iterator<const char*>(s), 10, input_iterator<const char*>(s+10)); 51 test(forward_iterator<const char*>(s), 10, forward_iterator<const char*>(s+10)); 52 test(bidirectional_iterator<const char*>(s+5), 5, bidirectional_iterator<const char*>(s+10)); 53 test(bidirectional_iterator<const char*>(s+5), -5, bidirectional_iterator<const char*>(s)); 54 test(random_access_iterator<const char*>(s+5), 5, random_access_iterator<const char*>(s+10)); 55 test(random_access_iterator<const char*>(s+5), -5, random_access_iterator<const char*>(s)); 56 test(s+5, 5, s+10); 57 test(s+5, -5, s); 58 } 59 #if TEST_STD_VER > 14 60 { 61 constexpr const char* s = "1234567890"; 62 static_assert( constepxr_test(input_iterator<const char*>(s), 10, input_iterator<const char*>(s+10)), "" ); 63 static_assert( constepxr_test(forward_iterator<const char*>(s), 10, forward_iterator<const char*>(s+10)), "" ); 64 static_assert( constepxr_test(bidirectional_iterator<const char*>(s+5), 5, bidirectional_iterator<const char*>(s+10)), "" ); 65 static_assert( constepxr_test(bidirectional_iterator<const char*>(s+5), -5, bidirectional_iterator<const char*>(s)), "" ); 66 static_assert( constepxr_test(random_access_iterator<const char*>(s+5), 5, random_access_iterator<const char*>(s+10)), "" ); 67 static_assert( constepxr_test(random_access_iterator<const char*>(s+5), -5, random_access_iterator<const char*>(s)), "" ); 68 static_assert( constepxr_test(s+5, 5, s+10), "" ); 69 static_assert( constepxr_test(s+5, -5, s), "" ); 70 } 71 #endif 72 } 73
