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 // reverse_iterator
13 
14 // requires RandomAccessIterator<Iter>
15 //   unspecified operator[](difference_type n) const;
16 
17 #include <iterator>
18 #include <cassert>
19 
20 #include "test_iterators.h"
21 
22 template <class It>
23 void
test(It i,typename std::iterator_traits<It>::difference_type n,typename std::iterator_traits<It>::value_type x)24 test(It i, typename std::iterator_traits<It>::difference_type n,
25      typename std::iterator_traits<It>::value_type x)
26 {
27     typedef typename std::iterator_traits<It>::value_type value_type;
28     const std::reverse_iterator<It> r(i);
29     value_type rr = r[n];
30     assert(rr == x);
31 }
32 
main()33 int main()
34 {
35     const char* s = "1234567890";
36     test(random_access_iterator<const char*>(s+5), 4, '1');
37     test(s+5, 4, '1');
38 }
39