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<class Iter>
13// struct iterator_traits
14// {
15//   typedef typename Iter::difference_type difference_type;
16//   typedef typename Iter::value_type value_type;
17//   typedef typename Iter::pointer pointer;
18//   typedef typename Iter::reference reference;
19//   typedef typename Iter::iterator_category iterator_category;
20// };
21
22#include <iterator>
23#include <type_traits>
24
25struct A {};
26
27struct test_iterator
28{
29    typedef int                       difference_type;
30    typedef A                         value_type;
31    typedef A*                        pointer;
32    typedef A&                        reference;
33    typedef std::forward_iterator_tag iterator_category;
34};
35
36int main()
37{
38    typedef std::iterator_traits<test_iterator> It;
39    static_assert((std::is_same<It::difference_type, int>::value), "");
40    static_assert((std::is_same<It::value_type, A>::value), "");
41    static_assert((std::is_same<It::pointer, A*>::value), "");
42    static_assert((std::is_same<It::iterator_category, std::forward_iterator_tag>::value), "");
43}
44