boost/type_erasure/check_match.hpp
// Boost.TypeErasure library
//
// Copyright 2011 Steven Watanabe
//
// 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)
//
// $Id$
#if !defined(BOOST_PP_IS_ITERATING)
#ifndef BOOST_TYPE_ERASURE_CHECK_MATCH_HPP_INCLUDED
#define BOOST_TYPE_ERASURE_CHECK_MATCH_HPP_INCLUDED
#include <boost/mpl/vector.hpp>
#include <boost/mpl/bool.hpp>
#include <boost/mpl/is_sequence.hpp>
#include <boost/mpl/find_if.hpp>
#include <boost/mpl/not.hpp>
#include <boost/mpl/end.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/preprocessor/cat.hpp>
#include <boost/preprocessor/iteration/iterate.hpp>
#include <boost/preprocessor/repetition/repeat.hpp>
#include <boost/preprocessor/repetition/enum_params.hpp>
#include <boost/preprocessor/repetition/enum_trailing_params.hpp>
#include <boost/preprocessor/repetition/enum_trailing_binary_params.hpp>
#include <boost/type_erasure/detail/extract_concept.hpp>
#include <boost/type_erasure/relaxed.hpp>
#include <boost/type_erasure/detail/access.hpp>
namespace boost {
namespace type_erasure {
template<class T>
struct typeid_;
template<class Concept>
class binding;
namespace detail {
template<class P, class T, class Table>
bool maybe_check_table(const T& arg, const Table*& table, boost::mpl::true_)
{
if(table == 0) {
table = &::boost::type_erasure::detail::access::table(arg);
return true;
} else {
return table->template find< ::boost::type_erasure::typeid_<P> >()() ==
::boost::type_erasure::detail::access::table(arg).
template find< ::boost::type_erasure::typeid_<P> >()();
}
}
template<class P, class T, class Table>
bool maybe_check_table(const T&, const Table*&, boost::mpl::false_)
{
return true;
}
template<class Concept, class T>
struct should_check :
boost::mpl::and_<
::boost::type_erasure::is_placeholder<T>,
::boost::type_erasure::is_relaxed<Concept>
>
{};
}
#ifdef BOOST_TYPE_ERASURE_DOXYGEN
/**
* If @ref relaxed is in @c Concept, checks whether the
* arguments to @c f match the types specified by
* @c binding. If @ref relaxed is not in @c Concept,
* returns true. If @c binding is not specified, it will
* be deduced from the arguments.
*/
template<class Concept, class Op, class... U>
bool check_match(const binding<Concept>& binding_arg, const Op& f, U&&... args);
/**
* \overload
*/
template<class Op, class... U>
bool check_match(const Op& f, U&&... args);
#else
#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
namespace detail {
template<class Concept>
bool check_table(const ::boost::type_erasure::binding<Concept>* t, void(*)())
{
return true;
}
template<class Concept, class R, class T0, class... T, class U0, class... U>
bool check_table(
const ::boost::type_erasure::binding<Concept>* t,
R(*)(T0, T...),
const U0& arg0,
const U&... arg)
{
typedef typename ::boost::remove_cv<
typename ::boost::remove_reference<T0>::type
>::type t0;
if(!::boost::type_erasure::detail::maybe_check_table<t0>(
arg0,
t,
::boost::type_erasure::detail::should_check<Concept, t0>()))
return false;
return check_table(t, static_cast<void(*)(T...)>(0), arg...);
}
}
template<class Concept, class Op, class... U>
bool check_match(
const ::boost::type_erasure::binding<Concept>& table,
const Op&,
U&&... arg)
{
return ::boost::type_erasure::detail::check_table(
&table,
static_cast<typename ::boost::type_erasure::detail::get_signature<Op>::type*>(0),
arg...);
}
template<
class Op,
class... U
>
bool check_match(
const Op&,
U&&... arg)
{
const ::boost::type_erasure::binding<
typename ::boost::type_erasure::detail::extract_concept<
typename ::boost::type_erasure::detail::get_signature<Op>::type, U...>::type>* p = 0;
return ::boost::type_erasure::detail::check_table(
p, static_cast<typename ::boost::type_erasure::detail::get_signature<Op>::type*>(0), arg...);
}
#else
#define BOOST_PP_FILENAME_1 <boost/type_erasure/check_match.hpp>
#define BOOST_PP_ITERATION_LIMITS (0, BOOST_TYPE_ERASURE_MAX_ARITY)
#include BOOST_PP_ITERATE()
#endif
#endif
}
}
#endif
#else
namespace detail {
#define N BOOST_PP_ITERATION()
#define BOOST_TYPE_ERASURE_CHECK_TABLE(z, n, data) \
typedef typename ::boost::remove_cv< \
typename ::boost::remove_reference<BOOST_PP_CAT(T, n)>::type \
>::type BOOST_PP_CAT(t, n); \
if(!::boost::type_erasure::detail::maybe_check_table<BOOST_PP_CAT(t, n)>( \
BOOST_PP_CAT(arg, n), \
t, \
::boost::type_erasure::detail::should_check<Concept, BOOST_PP_CAT(t, n)>())) \
return false;
template<
class Concept,
class R
BOOST_PP_ENUM_TRAILING_PARAMS(N, class T)
BOOST_PP_ENUM_TRAILING_PARAMS(N, class U)>
bool
BOOST_PP_CAT(check_table, N)(
const ::boost::type_erasure::binding<Concept>* t,
R (*)(BOOST_PP_ENUM_PARAMS(N, T))
BOOST_PP_ENUM_TRAILING_BINARY_PARAMS(N, const U, &arg))
{
BOOST_PP_REPEAT(N, BOOST_TYPE_ERASURE_CHECK_TABLE, ~)
return true;
}
#if N != 0
template<class Sig BOOST_PP_ENUM_TRAILING_PARAMS(N, class U)>
struct BOOST_PP_CAT(do_extract_concept, N);
template<
class R
BOOST_PP_ENUM_TRAILING_PARAMS(N, class T)
BOOST_PP_ENUM_TRAILING_PARAMS(N, class U)
>
struct BOOST_PP_CAT(do_extract_concept, N)<
R(BOOST_PP_ENUM_PARAMS(N, T))
BOOST_PP_ENUM_TRAILING_PARAMS(N, U)
>
: ::boost::type_erasure::detail::BOOST_PP_CAT(extract_concept, N)<
BOOST_PP_ENUM_PARAMS(N, T)
BOOST_PP_ENUM_TRAILING_PARAMS(N, U)>
{};
#endif
}
#ifdef BOOST_NO_CXX11_RVALUE_REFERENCES
#define RREF &
#else
#define RREF &&
#endif
template<
class Concept,
class Op
BOOST_PP_ENUM_TRAILING_PARAMS(N, class U)
>
bool check_match(
const ::boost::type_erasure::binding<Concept>& table,
const Op&
BOOST_PP_ENUM_TRAILING_BINARY_PARAMS(N, U, RREF arg))
{
return ::boost::type_erasure::detail::BOOST_PP_CAT(check_table, N)(
&table,
(typename ::boost::type_erasure::detail::get_signature<Op>::type*)0
BOOST_PP_ENUM_TRAILING_PARAMS(N, arg));
}
#if N != 0
template<
class Op
BOOST_PP_ENUM_TRAILING_PARAMS(N, class U)
>
bool check_match(
const Op&
BOOST_PP_ENUM_TRAILING_BINARY_PARAMS(N, U, RREF arg))
{
const ::boost::type_erasure::binding<
typename ::boost::type_erasure::detail::BOOST_PP_CAT(do_extract_concept, N)<
typename ::boost::type_erasure::detail::get_signature<Op>::type,
BOOST_PP_ENUM_PARAMS(N, U)>::type>* p = 0;
return ::boost::type_erasure::detail::BOOST_PP_CAT(check_table, N)(
p,
(typename ::boost::type_erasure::detail::get_signature<Op>::type*)0
BOOST_PP_ENUM_TRAILING_PARAMS(N, arg));
}
#undef RREF
#undef BOOST_TYPE_ERASURE_CHECK_TABLE
#undef N
#endif
#endif