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// Boost enable_if library
// Copyright 2003 (c) The Trustees of Indiana University.
// Use, modification, and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
// Authors: Jaakko Jarvi (jajarvi at osl.iu.edu)
// Jeremiah Willcock (jewillco at osl.iu.edu)
// Andrew Lumsdaine (lums at osl.iu.edu)
#include <boost/utility/enable_if.hpp>
#include <boost/type_traits/is_arithmetic.hpp>
#include <boost/core/lightweight_test.hpp>
using boost::enable_if_has_type;
using boost::enable_if_c;
using boost::disable_if_c;
using boost::enable_if;
using boost::disable_if;
using boost::is_arithmetic;
template <class T, class Enable = void>
struct tester;
template <class T>
struct tester<T, typename enable_if_c<is_arithmetic<T>::value>::type> {
BOOST_STATIC_CONSTANT(bool, value = true);
};
template <class T>
struct tester<T, typename disable_if_c<is_arithmetic<T>::value>::type> {
BOOST_STATIC_CONSTANT(bool, value = false);
};
template <class T, class Enable = void>
struct tester2;
template <class T>
struct tester2<T, typename enable_if<is_arithmetic<T> >::type> {
BOOST_STATIC_CONSTANT(bool, value = true);
};
template <class T>
struct tester2<T, typename disable_if<is_arithmetic<T> >::type> {
BOOST_STATIC_CONSTANT(bool, value = false);
};
template <class T, class Enable = void>
struct tester3
{
typedef T type;
BOOST_STATIC_CONSTANT(bool, value = false);
};
template <class T>
struct tester3<T, typename enable_if_has_type<typename T::value_type>::type>
{
typedef typename T::value_type type;
BOOST_STATIC_CONSTANT(bool, value = true);
};
struct sample_value_type
{
typedef float***& value_type;
};
int main()
{
BOOST_TEST(tester<int>::value);
BOOST_TEST(tester<double>::value);
BOOST_TEST(!tester<char*>::value);
BOOST_TEST(!tester<void*>::value);
BOOST_TEST(tester2<int>::value);
BOOST_TEST(tester2<double>::value);
BOOST_TEST(!tester2<char*>::value);
BOOST_TEST(!tester2<void*>::value);
BOOST_TEST(!tester3<char*>::value);
BOOST_TEST(tester3<sample_value_type>::value);
return boost::report_errors();
}
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