1 | // Boost enable_if library |
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2 | |
3 | // Copyright 2003 (c) The Trustees of Indiana University. |
4 | |
5 | // Use, modification, and distribution is subject to the Boost Software |
6 | // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
7 | // http://www.boost.org/LICENSE_1_0.txt) |
8 | |
9 | // Authors: Jaakko Jarvi (jajarvi at osl.iu.edu) |
10 | // Jeremiah Willcock (jewillco at osl.iu.edu) |
11 | // Andrew Lumsdaine (lums at osl.iu.edu) |
12 | |
13 | #include <boost/config.hpp> |
14 | #include <boost/utility/enable_if.hpp> |
15 | #include <boost/type_traits/is_arithmetic.hpp> |
16 | #include <boost/core/lightweight_test.hpp> |
17 | |
18 | using boost::enable_if; |
19 | using boost::is_arithmetic; |
20 | |
21 | template<class T> struct not_ |
22 | { |
23 | BOOST_STATIC_CONSTANT( bool, value = !T::value ); |
24 | }; |
25 | |
26 | template<class T> |
27 | typename enable_if<is_arithmetic<T>, bool>::type |
28 | arithmetic_object(T /*t*/) { return true; } |
29 | |
30 | template<class T> |
31 | typename enable_if<not_<is_arithmetic<T> >, bool>::type |
32 | arithmetic_object(T /*t*/) { return false; } |
33 | |
34 | |
35 | int main() |
36 | { |
37 | |
38 | BOOST_TEST(arithmetic_object(1)); |
39 | BOOST_TEST(arithmetic_object(1.0)); |
40 | |
41 | BOOST_TEST(!arithmetic_object("1")); |
42 | BOOST_TEST(!arithmetic_object(static_cast<void*>(0))); |
43 | |
44 | return boost::report_errors(); |
45 | } |
46 |