Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: /// \file template_arity.hpp
Chris@16: /// Replace all nodes stored by reference by nodes stored by value.
Chris@16: //
Chris@16: //  Copyright 2011 Eric Niebler. Distributed under the Boost
Chris@16: //  Software License, Version 1.0. (See accompanying file
Chris@16: //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16: //
Chris@16: //  This file is based on a similar one in MPL from Aleksey Gurtovoy.
Chris@16: 
Chris@16: #ifndef BOOST_PROTO_DETAIL_TEMPLATE_ARITY_HPP_EAN_2011_05_07
Chris@16: #define BOOST_PROTO_DETAIL_TEMPLATE_ARITY_HPP_EAN_2011_05_07
Chris@16: 
Chris@16: // Somewhat indirect definition of BOOST_PROTO_TEMPLATE_ARITY_PARAM is
Chris@16: // to overcome a shortcoming of the Wave tool used to generate the
Chris@16: // pre-preprocessed headers.
Chris@16: #define BOOST_PROTO_TEMPLATE_ARITY_PARAM BOOST_PROTO_TEMPLATE_ARITY_PARAM2
Chris@16: #define BOOST_PROTO_TEMPLATE_ARITY_PARAM2(param)
Chris@16: 
Chris@16: #if defined(BOOST_PROTO_EXTENDED_TEMPLATE_PARAMETERS_MATCHING) ||                                   \
Chris@16:   (defined(__WAVE__) && defined(BOOST_PROTO_CREATE_PREPROCESSED_FILES))
Chris@16: 
Chris@16: #include <boost/preprocessor/cat.hpp>
Chris@16: #include <boost/preprocessor/inc.hpp>
Chris@16: #include <boost/preprocessor/iteration/iterate.hpp>
Chris@16: #include <boost/preprocessor/repetition/enum_params.hpp>
Chris@16: #include <boost/mpl/int.hpp>
Chris@16: #include <boost/proto/proto_fwd.hpp>
Chris@16: 
Chris@16: #undef BOOST_PROTO_TEMPLATE_ARITY_PARAM2
Chris@16: #define BOOST_PROTO_TEMPLATE_ARITY_PARAM2(param) , param
Chris@16: 
Chris@16: namespace boost { namespace proto { namespace detail
Chris@16: {
Chris@16:     sized_type<1>::type template_arity_helper(...);
Chris@16: 
Chris@16:     // Other overloads generated by the preprocessor
Chris@16:     #include <boost/proto/detail/template_arity_helper.hpp>
Chris@16: 
Chris@16:     template<typename F, int N, int Size>
Chris@16:     struct template_arity_impl2
Chris@16:       : mpl::int_<Size - 1>
Chris@16:     {};
Chris@16: 
Chris@16:     template<typename F, int N = BOOST_PROTO_MAX_ARITY>
Chris@16:     struct template_arity
Chris@16:       : template_arity_impl2<
Chris@16:             F
Chris@16:           , N
Chris@16:           , sizeof(detail::template_arity_helper((F **)0, (mpl::int_<N> *)0))
Chris@16:         >
Chris@16:     {};
Chris@16: 
Chris@16:     template<typename F, int N>
Chris@16:     struct template_arity_impl2<F, N, 1>
Chris@16:       : template_arity<F, N-1>
Chris@16:     {};
Chris@16: 
Chris@16:     template<typename F>
Chris@16:     struct template_arity_impl2<F, 0, 1>
Chris@16:       : mpl::int_<-1>
Chris@16:     {};
Chris@16: 
Chris@16: }}}
Chris@16: 
Chris@16: #endif // BOOST_PROTO_EXTENDED_TEMPLATE_PARAMETERS_MATCHING
Chris@16: #endif // BOOST_PROTO_DETAIL_TEMPLATE_ARITY_HPP_EAN_2011_05_07