114 lines
4.1 KiB
Plaintext
114 lines
4.1 KiB
Plaintext
#if !defined(BOOST_PROTO_DONT_USE_PREPROCESSED_FILES)
|
|
|
|
#include <boost/proto/context/detail/preprocessed/callable_eval.hpp>
|
|
|
|
#elif !defined(BOOST_PP_IS_ITERATING)
|
|
|
|
#define BOOST_PROTO_CHILD_N_TYPE(Z, N, Expr) \
|
|
typedef typename proto::result_of::child_c<Expr const &, N>::type BOOST_PP_CAT(child, N); \
|
|
/**/
|
|
|
|
#define BOOST_PROTO_CHILD_N(Z, N, expr) \
|
|
proto::child_c<N>(expr) \
|
|
/**/
|
|
|
|
#if defined(__WAVE__) && defined(BOOST_PROTO_CREATE_PREPROCESSED_FILES)
|
|
#pragma wave option(preserve: 2, line: 0, output: "preprocessed/callable_eval.hpp")
|
|
#endif
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
/// \file callable_eval.hpp
|
|
/// Contains specializations of the callable_eval\<\> class template.
|
|
//
|
|
// 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)
|
|
|
|
#if defined(__WAVE__) && defined(BOOST_PROTO_CREATE_PREPROCESSED_FILES)
|
|
#pragma wave option(preserve: 1)
|
|
#endif
|
|
|
|
#define BOOST_PP_ITERATION_PARAMS_1 \
|
|
(3, (1, BOOST_PROTO_MAX_ARITY, <boost/proto/context/detail/callable_eval.hpp>))
|
|
#include BOOST_PP_ITERATE()
|
|
|
|
#if defined(__WAVE__) && defined(BOOST_PROTO_CREATE_PREPROCESSED_FILES)
|
|
#pragma wave option(output: null)
|
|
#endif
|
|
|
|
#undef BOOST_PROTO_CHILD_N_TYPE
|
|
#undef BOOST_PROTO_CHILD_N
|
|
|
|
#else
|
|
|
|
#define N BOOST_PP_ITERATION()
|
|
|
|
namespace detail
|
|
{
|
|
template<typename Expr, typename Context>
|
|
struct is_expr_handled<Expr, Context, N>
|
|
{
|
|
static callable_context_wrapper<Context> &sctx_;
|
|
static Expr &sexpr_;
|
|
static typename Expr::proto_tag &stag_;
|
|
|
|
static const bool value =
|
|
sizeof(yes_type) ==
|
|
sizeof(
|
|
detail::check_is_expr_handled(
|
|
(sctx_(
|
|
stag_
|
|
BOOST_PP_ENUM_TRAILING(N, BOOST_PROTO_CHILD_N, sexpr_)
|
|
), 0)
|
|
)
|
|
);
|
|
|
|
typedef mpl::bool_<value> type;
|
|
};
|
|
}
|
|
|
|
namespace context
|
|
{
|
|
/// \brief A BinaryFunction that accepts a Proto expression and a
|
|
/// callable context and calls the context with the expression tag
|
|
/// and children as arguments, effectively fanning the expression
|
|
/// out.
|
|
///
|
|
/// <tt>callable_eval\<\></tt> requires that \c Context is a
|
|
/// PolymorphicFunctionObject that can be invoked with \c Expr's
|
|
/// tag and children as expressions, as follows:
|
|
///
|
|
/// \code
|
|
/// context(Expr::proto_tag(), child_c\<0\>(expr), child_c\<1\>(expr), ...)
|
|
/// \endcode
|
|
template<typename Expr, typename Context>
|
|
struct callable_eval<Expr, Context, N>
|
|
{
|
|
BOOST_PP_REPEAT(N, BOOST_PROTO_CHILD_N_TYPE, Expr)
|
|
|
|
typedef
|
|
typename BOOST_PROTO_RESULT_OF<
|
|
Context(
|
|
typename Expr::proto_tag
|
|
BOOST_PP_ENUM_TRAILING_PARAMS(N, child)
|
|
)
|
|
>::type
|
|
result_type;
|
|
|
|
/// \param expr The current expression
|
|
/// \param context The callable evaluation context
|
|
/// \return <tt>context(Expr::proto_tag(), child_c\<0\>(expr), child_c\<1\>(expr), ...)</tt>
|
|
result_type operator ()(Expr &expr, Context &context) const
|
|
{
|
|
return context(
|
|
typename Expr::proto_tag()
|
|
BOOST_PP_ENUM_TRAILING(N, BOOST_PROTO_CHILD_N, expr)
|
|
);
|
|
}
|
|
};
|
|
}
|
|
|
|
#undef N
|
|
|
|
#endif
|