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 // <locale>
11 
12 // template <class Facet> const Facet& use_facet(const locale& loc);
13 
14 #include <locale>
15 #include <cassert>
16 
17 int facet_count = 0;
18 
19 struct my_facet
20     : public std::locale::facet
21 {
22     static std::locale::id id;
23 
24     bool im_alive;
25 
my_facetmy_facet26     my_facet() : im_alive(true) {++facet_count;}
~my_facetmy_facet27     ~my_facet() {im_alive = false; --facet_count;}
28 };
29 
30 std::locale::id my_facet::id;
31 
main()32 int main()
33 {
34     try
35     {
36         const my_facet& f = std::use_facet<my_facet>(std::locale());
37         assert(false);
38     }
39     catch (std::bad_cast&)
40     {
41     }
42     const my_facet* fp = 0;
43     {
44         std::locale loc(std::locale(), new my_facet);
45         const my_facet& f = std::use_facet<my_facet>(loc);
46         assert(f.im_alive);
47         fp = &f;
48         assert(fp->im_alive);
49         assert(facet_count == 1);
50     }
51     assert(facet_count == 0);
52 }
53