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 // <deque>
11 
12 // void pop_front()
13 
14 //  Erasing items from the beginning or the end of a deque shall not invalidate iterators
15 //  to items that were not erased.
16 
17 #include <deque>
18 #include <cassert>
19 
20 template <typename C>
test(C c)21 void test(C c)
22 {
23     typename C::iterator it1 = c.begin() + 1;
24     typename C::iterator it2 = c.end() - 1;
25 
26     c.pop_front();
27 
28     typename C::iterator it3 = c.begin();
29     typename C::iterator it4 = c.end() - 1;
30     assert(  it1 ==   it3);
31     assert( *it1 ==  *it3);
32     assert(&*it1 == &*it3);
33     assert(  it2 ==   it4);
34     assert( *it2 ==  *it4);
35     assert(&*it2 == &*it4);
36 }
37 
main()38 int main()
39 {
40     std::deque<int> queue;
41     for (int i = 0; i < 20; ++i)
42         queue.push_back(i);
43 
44     while (queue.size() > 1)
45     {
46         test(queue);
47         queue.pop_back();
48     }
49 }
50