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 // <functional>
11 
12 // negate
13 
14 #include <functional>
15 #include <type_traits>
16 #include <cassert>
17 
main()18 int main()
19 {
20     typedef std::negate<int> F;
21     const F f = F();
22     static_assert((std::is_base_of<std::unary_function<int, int>, F>::value), "");
23     assert(f(36) == -36);
24 #if _LIBCPP_STD_VER > 11
25     typedef std::negate<> F2;
26     const F2 f2 = F2();
27     assert(f2(36) == -36);
28     assert(f2(36L) == -36);
29     assert(f2(36.0) == -36);
30 
31     constexpr int foo = std::negate<int> () (3);
32     static_assert ( foo == -3, "" );
33 
34     constexpr int bar = std::negate<> () (3.0);
35     static_assert ( bar == -3, "" );
36 #endif
37 }
38