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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)
#ifndef BOOST_UTILITY_ENABLE_IF_HPP
#define BOOST_UTILITY_ENABLE_IF_HPP
#include "ndnboost/config.hpp"
// Even the definition of enable_if causes problems on some compilers,
// so it's macroed out for all compilers that do not support SFINAE
#ifndef BOOST_NO_SFINAE
namespace ndnboost
{
template <bool B, class T = void>
struct enable_if_c {
typedef T type;
};
template <class T>
struct enable_if_c<false, T> {};
template <class Cond, class T = void>
struct enable_if : public enable_if_c<Cond::value, T> {};
template <bool B, class T>
struct lazy_enable_if_c {
typedef typename T::type type;
};
template <class T>
struct lazy_enable_if_c<false, T> {};
template <class Cond, class T>
struct lazy_enable_if : public lazy_enable_if_c<Cond::value, T> {};
template <bool B, class T = void>
struct disable_if_c {
typedef T type;
};
template <class T>
struct disable_if_c<true, T> {};
template <class Cond, class T = void>
struct disable_if : public disable_if_c<Cond::value, T> {};
template <bool B, class T>
struct lazy_disable_if_c {
typedef typename T::type type;
};
template <class T>
struct lazy_disable_if_c<true, T> {};
template <class Cond, class T>
struct lazy_disable_if : public lazy_disable_if_c<Cond::value, T> {};
} // namespace ndnboost
#else
namespace ndnboost {
namespace detail { typedef void enable_if_default_T; }
template <typename T>
struct enable_if_does_not_work_on_this_compiler;
template <bool B, class T = detail::enable_if_default_T>
struct enable_if_c : enable_if_does_not_work_on_this_compiler<T>
{ };
template <bool B, class T = detail::enable_if_default_T>
struct disable_if_c : enable_if_does_not_work_on_this_compiler<T>
{ };
template <bool B, class T = detail::enable_if_default_T>
struct lazy_enable_if_c : enable_if_does_not_work_on_this_compiler<T>
{ };
template <bool B, class T = detail::enable_if_default_T>
struct lazy_disable_if_c : enable_if_does_not_work_on_this_compiler<T>
{ };
template <class Cond, class T = detail::enable_if_default_T>
struct enable_if : enable_if_does_not_work_on_this_compiler<T>
{ };
template <class Cond, class T = detail::enable_if_default_T>
struct disable_if : enable_if_does_not_work_on_this_compiler<T>
{ };
template <class Cond, class T = detail::enable_if_default_T>
struct lazy_enable_if : enable_if_does_not_work_on_this_compiler<T>
{ };
template <class Cond, class T = detail::enable_if_default_T>
struct lazy_disable_if : enable_if_does_not_work_on_this_compiler<T>
{ };
} // namespace ndnboost
#endif // BOOST_NO_SFINAE
#endif