exchange.pass.cpp revision 171771a9f5fd9e5dbbc6d6a2d9dfb0d8532b5155 
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// utilities
11
12// exchange
13
14#include <utility>
15#include <cassert>
16#include <string>
17
18int main()
19{
20#if _LIBCPP_STD_VER > 11
21    {
22    int v = 12;
23    assert ( std::exchange ( v, 23 ) == 12 );
24    assert ( v == 23 );
25    assert ( std::exchange ( v, 67.2 ) == 23 );
26    assert ( v = 67 );
27    }
28
29    {
30    bool b = false;
31    assert ( !std::exchange ( b, true ));
32    assert ( b );
33    }
34
35    {
36    const std::string s1 ( "Hi Mom!" );
37    const std::string s2 ( "Yo Dad!" );
38    std::string s3 = s1; // Mom
39    assert ( std::exchange ( s3, s2 ) == s1 );
40    assert ( s3 == s2 );
41    assert ( std::exchange ( s3, "Hi Mom!" ) == s2 );
42    assert ( s3 == s1 );
43    assert ( std::exchange ( s3, "" ) == s1 );
44    assert ( s3.size () == 0 );
45    }
46#endif
47}
48