boost/proto/args.hpp
#ifndef BOOST_PP_IS_ITERATING
///////////////////////////////////////////////////////////////////////////////
/// \file args.hpp
/// Contains definition of \c term\<\>, \c list1\<\>, \c list2\<\>, ...
/// class templates.
//
// Copyright 2008 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)
#ifndef BOOST_PROTO_ARGS_HPP_EAN_04_01_2005
#define BOOST_PROTO_ARGS_HPP_EAN_04_01_2005
#include <iosfwd>
#include <boost/config.hpp>
#include <boost/detail/workaround.hpp>
#include <boost/preprocessor/cat.hpp>
#include <boost/preprocessor/arithmetic/dec.hpp>
#include <boost/preprocessor/iteration/iterate.hpp>
#include <boost/preprocessor/repetition/enum_params.hpp>
#include <boost/preprocessor/repetition/repeat.hpp>
#include <boost/preprocessor/repetition/repeat_from_to.hpp>
#include <boost/type_traits/is_function.hpp>
#include <boost/type_traits/is_abstract.hpp>
#include <boost/type_traits/is_base_of.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/or.hpp>
#include <boost/mpl/void.hpp>
#include <boost/proto/proto_fwd.hpp>
namespace boost { namespace proto
{
namespace detail
{
/// INTERNAL ONLY
template<typename T>
struct ref_only
: mpl::or_<
is_function<T>
, is_abstract<T>
, is_base_of<std::ios_base, T>
>
{};
/// INTERNAL ONLY
template<typename Expr>
struct expr_traits
{
typedef Expr value_type;
typedef Expr &reference;
typedef Expr const &const_reference;
};
/// INTERNAL ONLY
template<typename Expr>
struct expr_traits<Expr &>
{
typedef Expr value_type;
typedef Expr &reference;
typedef Expr &const_reference;
};
/// INTERNAL ONLY
template<typename Expr>
struct expr_traits<Expr const &>
{
typedef Expr value_type;
typedef Expr const &reference;
typedef Expr const &const_reference;
};
/// INTERNAL ONLY
template<typename T>
struct term_traits
{
typedef T value_type;
typedef T &reference;
typedef T const &const_reference;
};
/// INTERNAL ONLY
template<typename T>
struct term_traits<T &>
{
typedef typename mpl::if_c<ref_only<T>::value, T &, T>::type value_type;
typedef T &reference;
typedef T &const_reference;
};
/// INTERNAL ONLY
template<typename T>
struct term_traits<T const &>
{
typedef T value_type;
typedef T const &reference;
typedef T const &const_reference;
};
/// INTERNAL ONLY
template<typename T, std::size_t N>
struct term_traits<T (&)[N]>
{
typedef T value_type[N];
typedef T (&reference)[N];
typedef T (&const_reference)[N];
};
/// INTERNAL ONLY
template<typename T, std::size_t N>
struct term_traits<T const (&)[N]>
{
typedef T value_type[N];
typedef T const (&reference)[N];
typedef T const (&const_reference)[N];
};
/// INTERNAL ONLY
template<typename T, std::size_t N>
struct term_traits<T[N]>
{
typedef T value_type[N];
typedef T (&reference)[N];
typedef T const (&const_reference)[N];
};
/// INTERNAL ONLY
template<typename T, std::size_t N>
struct term_traits<T const[N]>
{
typedef T value_type[N];
typedef T const (&reference)[N];
typedef T const (&const_reference)[N];
};
}
////////////////////////////////////////////////////////////////////////////////////////////
#define BOOST_PROTO_DEFINE_CHILD_N(Z, N, DATA) \
typedef BOOST_PP_CAT(Arg, N) BOOST_PP_CAT(child, N); \
/**< INTERNAL ONLY */
#define BOOST_PROTO_DEFINE_VOID_N(z, n, data) \
typedef mpl::void_ BOOST_PP_CAT(child, n); \
/**< INTERNAL ONLY */
namespace argsns_
{
/// \brief A type sequence, for use as the 2nd parameter to the \c expr\<\> class template.
///
/// A type sequence, for use as the 2nd parameter to the \c expr\<\> class template.
/// The types in the sequence correspond to the children of a node in an expression tree.
template< typename Arg0 >
struct term
{
BOOST_STATIC_CONSTANT(long, arity = 0);
typedef Arg0 child0;
#if BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1500))
BOOST_PP_REPEAT_FROM_TO(1, BOOST_PROTO_MAX_ARITY, BOOST_PROTO_DEFINE_VOID_N, ~)
#endif
/// INTERNAL ONLY
///
typedef Arg0 back_;
};
#define BOOST_PP_ITERATION_PARAMS_1 (3, (1, BOOST_PROTO_MAX_ARITY, <boost/proto/args.hpp>))
#include BOOST_PP_ITERATE()
#undef BOOST_PROTO_DEFINE_CHILD_N
}
////////////////////////////////////////////////////////////////////////////////////////////
}}
#endif
#else
#define N BOOST_PP_ITERATION()
/// \brief A type sequence, for use as the 2nd parameter to the \c expr\<\> class template.
///
/// A type sequence, for use as the 2nd parameter to the \c expr\<\> class template.
/// The types in the sequence correspond to the children of a node in an expression tree.
template< BOOST_PP_ENUM_PARAMS(N, typename Arg) >
struct BOOST_PP_CAT(list, N)
{
BOOST_STATIC_CONSTANT(long, arity = N);
BOOST_PP_REPEAT(N, BOOST_PROTO_DEFINE_CHILD_N, ~)
#if BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1500))
BOOST_PP_REPEAT_FROM_TO(N, BOOST_PROTO_MAX_ARITY, BOOST_PROTO_DEFINE_VOID_N, ~)
#endif
/// INTERNAL ONLY
///
typedef BOOST_PP_CAT(Arg, BOOST_PP_DEC(N)) back_;
};
#undef N
#endif
