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///////////////////////////////////////////////////////////////////////////////
/// \file deduce_domain.hpp
/// Contains definition of deduce_domain\<\> class templates
/// for finding the domain that is common among the specified
/// domains
//
// Copyright 2010 Daniel Wallin, Eric Niebler. Distributed under 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)
//
// Many thanks to Daniel Wallin who first implemented this code. Thanks
// also to Jeremiah Willcock, John Bytheway and Krishna Achuthan who
// offered alternate solutions to this tricky programming problem.
#ifndef BOOST_PROTO_DEDUCE_DOMAIN_HPP_EAN_05_22_2010
#define BOOST_PROTO_DEDUCE_DOMAIN_HPP_EAN_05_22_2010
#include <boost/config.hpp>
#include <boost/preprocessor/cat.hpp>
#include <boost/preprocessor/facilities/intercept.hpp>
#include <boost/preprocessor/iteration/local.hpp>
#include <boost/preprocessor/iteration/iterate.hpp>
#include <boost/preprocessor/repetition/enum_params.hpp>
#include <boost/preprocessor/repetition/enum_binary_params.hpp>
#include <boost/preprocessor/repetition/repeat_from_to.hpp>
#include <boost/preprocessor/arithmetic/inc.hpp>
#include <boost/mpl/assert.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/proto/proto_fwd.hpp>
#ifndef BOOST_PROTO_ASSERT_VALID_DOMAIN
# define BOOST_PROTO_ASSERT_VALID_DOMAIN(DOM) BOOST_MPL_ASSERT_NOT((boost::is_same<DOM, boost::proto::detail::not_a_domain>))
#endif
namespace boost
{
namespace proto
{
namespace detail
{
template<typename Domain>
struct domain_
: domain_<typename Domain::proto_super_domain>
{
typedef Domain type;
typedef domain_<typename Domain::proto_super_domain> base;
#ifdef BOOST_NO_CXX11_DECLTYPE
using base::deduce98;
static int const index = base::index + 1;
static typename sized_type<index>::type deduce98(domain_<Domain>*);
#else
using base::deduce0x;
static Domain deduce0x(domain_<Domain>*);
#endif
};
template<>
struct domain_<not_a_domain>
{
typedef not_a_domain type;
#ifdef BOOST_NO_CXX11_DECLTYPE
static int const index = 1;
static sized_type<1>::type deduce98(void*);
#else
static not_a_domain deduce0x(void*);
#endif
};
template<>
struct domain_<default_domain>
: domain_<not_a_domain>
{};
template<>
struct domain_<basic_default_domain>
: domain_<not_a_domain>
{};
sized_type<1>::type default_test(void*, void*);
sized_type<2>::type default_test(domain_<default_domain>*, void*);
sized_type<2>::type default_test(domain_<basic_default_domain>*, void*);
sized_type<3>::type default_test(void*, domain_<default_domain>*);
sized_type<3>::type default_test(void*, domain_<basic_default_domain>*);
sized_type<4>::type default_test(domain_<default_domain>*, domain_<default_domain>*);
sized_type<4>::type default_test(domain_<basic_default_domain>*, domain_<default_domain>*);
sized_type<4>::type default_test(domain_<default_domain>*, domain_<basic_default_domain>*);
sized_type<4>::type default_test(domain_<basic_default_domain>*, domain_<basic_default_domain>*);
#ifdef BOOST_NO_CXX11_DECLTYPE
template<int N, typename Domain>
struct nth_domain
: nth_domain<N - 1, typename Domain::base>
{};
template<typename Domain>
struct nth_domain<0, Domain>
: Domain
{};
#endif
template<typename D0>
struct common_domain1
{
typedef D0 type;
};
template<typename E0>
struct deduce_domain1
: domain_of<E0>
{};
template<
typename D0
, typename D1
, int DefaultCase = sizeof(proto::detail::default_test((domain_<D0>*)0, (domain_<D1>*)0))
>
struct common_domain2
{
#ifdef BOOST_NO_CXX11_DECLTYPE
static int const index = domain_<D0>::index - sizeof(domain_<D0>::deduce98((domain_<D1>*)0));
typedef typename nth_domain<index, domain_<D0> >::type type;
#else
typedef decltype(domain_<D0>::deduce0x((domain_<D1>*)0)) type;
#endif
};
template<typename D0, typename D1>
struct common_domain2<D0, D1, 2>
{
typedef D1 type;
};
template<typename D0, typename D1>
struct common_domain2<D0, D1, 3>
{
typedef D0 type;
};
template<typename D0>
struct common_domain2<D0, default_domain, 4>
{
typedef D0 type;
};
template<typename D0>
struct common_domain2<D0, basic_default_domain, 4>
{
typedef D0 type;
};
template<typename D1>
struct common_domain2<default_domain, D1, 4>
{
typedef D1 type;
};
template<typename D1>
struct common_domain2<basic_default_domain, D1, 4>
{
typedef D1 type;
};
template<>
struct common_domain2<default_domain, default_domain, 4>
{
typedef default_domain type;
};
template<>
struct common_domain2<basic_default_domain, default_domain, 4>
{
typedef default_domain type;
};
template<>
struct common_domain2<default_domain, basic_default_domain, 4>
{
typedef default_domain type;
};
template<>
struct common_domain2<basic_default_domain, basic_default_domain, 4>
{
typedef basic_default_domain type;
};
template<typename E0, typename E1>
struct deduce_domain2
: common_domain2<
typename domain_of<E0>::type
, typename domain_of<E1>::type
>
{};
#include <boost/proto/detail/deduce_domain_n.hpp>
}
}
}
#endif // BOOST_PROTO_DEDUCE_DOMAIN_HPP_EAN_05_22_2010