difference_type.pass.cpp revision f333beee2ce44299b1ce219371bdef60290ac175 
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// move_iterator
13
14// requires RandomAccessIterator<Iter>
15//   move_iterator& operator+=(difference_type n);
16//
17//  constexpr in C++17
18
19#include <iterator>
20#include <cassert>
21
22#include "test_macros.h"
23#include "test_iterators.h"
24
25template <class It>
26void
27test(It i, typename std::iterator_traits<It>::difference_type n, It x)
28{
29    std::move_iterator<It> r(i);
30    std::move_iterator<It>& rr = r += n;
31    assert(r.base() == x);
32    assert(&rr == &r);
33}
34
35int main()
36{
37    const char* s = "1234567890";
38    test(random_access_iterator<const char*>(s+5), 5, random_access_iterator<const char*>(s+10));
39    test(s+5, 5, s+10);
40
41#if TEST_STD_VER > 14
42    {
43    constexpr const char *p = "123456789";
44    typedef std::move_iterator<const char *> MI;
45    constexpr MI it1 = std::make_move_iterator(p);
46    constexpr MI it2 = std::make_move_iterator(p + 5);
47    constexpr MI it3 = std::make_move_iterator(p) += 5;
48    static_assert(it1 != it2, "");
49    static_assert(it1 != it3, "");
50    static_assert(it2 == it3, "");
51    }
52#endif
53}
54