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 // template <BidirectionalIterator Iter> 13 // Iter prev(Iter x, Iter::difference_type n = 1); 14 15 #include <iterator> 16 #include <cassert> 17 18 #include "test_iterators.h" 19 20 template <class It> 21 void 22 test(It i, typename std::iterator_traits<It>::difference_type n, It x) 23 { 24 assert(std::prev(i, n) == x); 25 } 26 27 template <class It> 28 void 29 test(It i, It x) 30 { 31 assert(std::prev(i) == x); 32 } 33 34 int main() 35 { 36 const char* s = "1234567890"; 37 test(bidirectional_iterator<const char*>(s+10), 10, bidirectional_iterator<const char*>(s)); 38 test(random_access_iterator<const char*>(s+10), 10, random_access_iterator<const char*>(s)); 39 test(s+10, 10, s); 40 41 test(bidirectional_iterator<const char*>(s+1), bidirectional_iterator<const char*>(s)); 42 test(random_access_iterator<const char*>(s+1), random_access_iterator<const char*>(s)); 43 test(s+1, s); 44 } 45
