1// (C) Copyright John Maddock 2010.
2// Use, modification and distribution are subject to the Boost Software License,
3// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
4// http://www.boost.org/LICENSE_1_0.txt).
5//
6// See http://www.boost.org/libs/type_traits for most recent version including documentation.
7
8
9#ifndef BOOST_TT_CONDITIONAL_HPP_INCLUDED
10#define BOOST_TT_CONDITIONAL_HPP_INCLUDED
11
12#include <boost/config.hpp>
13
14namespace boost {
15
16template <bool b, class T, class U> struct conditional { typedef T type; };
17template <class T, class U> struct conditional<false, T, U> { typedef U type; };
18
19#if !defined(BOOST_NO_CXX11_TEMPLATE_ALIASES)
20
21 template <bool b, class T, class U> using conditional_t = typename conditional<b, T, U>::type;
22
23#endif
24
25} // namespace boost
26
27
28#endif // BOOST_TT_CONDITIONAL_HPP_INCLUDED
29