boost/type_erasure/detail/dynamic_vtable.hpp
// Boost.TypeErasure library
//
// Copyright 2015 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)
//
// $Id$
#ifndef BOOST_TYPE_ERASURE_DETAIL_DYNAMIC_VTABLE_HPP_INCLUDED
#define BOOST_TYPE_ERASURE_DETAIL_DYNAMIC_VTABLE_HPP_INCLUDED
#include <boost/type_erasure/detail/get_placeholders.hpp>
#include <boost/type_erasure/detail/rebind_placeholders.hpp>
#include <boost/type_erasure/detail/normalize.hpp>
#include <boost/type_erasure/detail/adapt_to_vtable.hpp>
#include <boost/type_erasure/detail/vtable.hpp>
#include <boost/type_erasure/static_binding.hpp>
#include <boost/type_erasure/register_binding.hpp>
#include <boost/mpl/transform.hpp>
#include <boost/mpl/at.hpp>
#include <boost/mpl/set.hpp>
#include <boost/mpl/for_each.hpp>
#include <boost/mpl/index_of.hpp>
#include <typeinfo>
namespace boost {
namespace type_erasure {
namespace detail {
#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_CONSTEXPR) && !defined(BOOST_NO_CXX11_DEFAULTED_FUNCTIONS)
template<class P>
struct dynamic_binding_impl {
const std::type_info * type;
dynamic_binding_impl() = default;
constexpr dynamic_binding_impl(const std::type_info * t) : type(t) {}
};
template<class T>
struct dynamic_binding_element {
typedef const std::type_info * type;
};
template<class Table>
struct append_to_key {
template<class P>
void operator()(P) {
key->push_back(static_cast<const dynamic_binding_impl<P>*>(table)->type);
}
const Table * table;
key_type * key;
};
template<class... P>
struct dynamic_vtable : dynamic_binding_impl<P>... {
dynamic_vtable() = default;
constexpr dynamic_vtable(typename dynamic_binding_element<P>::type ...t) : dynamic_binding_impl<P>(t)... {}
template<class F>
typename F::type lookup(F*) const {
key_type key;
#ifndef BOOST_TYPE_ERASURE_USE_MP11
typedef typename ::boost::type_erasure::detail::get_placeholders<F, ::boost::mpl::set0<> >::type placeholders;
#else
typedef typename ::boost::type_erasure::detail::get_placeholders<F, ::boost::mp11::mp_list<> >::type placeholders;
#endif
typedef typename ::boost::mpl::fold<
placeholders,
::boost::mpl::map0<>,
::boost::type_erasure::detail::counting_map_appender
>::type placeholder_map;
key.push_back(&typeid(typename ::boost::type_erasure::detail::rebind_placeholders<F, placeholder_map>::type));
::boost::mpl::for_each<placeholders>(append_to_key<dynamic_vtable>{this, &key});
return reinterpret_cast<typename F::type>(lookup_function_impl(key));
}
template<class Bindings>
void init() {
*this = dynamic_vtable(&typeid(typename boost::mpl::at<Bindings, P>::type)...);
}
template<class Bindings, class Src>
void convert_from(const Src& src) {
#ifndef BOOST_TYPE_ERASURE_USE_MP11
*this = dynamic_vtable(
(&src.lookup((::boost::type_erasure::typeid_<typename ::boost::mpl::at<Bindings, P>::type>*)0)())...);
#else
*this = dynamic_vtable(
(&src.lookup((::boost::type_erasure::typeid_< ::boost::mp11::mp_second< ::boost::mp11::mp_map_find<Bindings, P> > >*)0)())...);
#endif
}
};
template<class L>
struct make_dynamic_vtable_impl;
template<class... P>
struct make_dynamic_vtable_impl<stored_arg_pack<P...> >
{
typedef dynamic_vtable<P...> type;
};
template<class PlaceholderList>
struct make_dynamic_vtable
: make_dynamic_vtable_impl<typename make_arg_pack<PlaceholderList>::type>
{};
#else
template<class Bindings>
struct dynamic_vtable_initializer
{
dynamic_vtable_initializer(const std::type_info**& ptr) : types(&ptr) {}
template<class P>
void operator()(P)
{
*(*types)++ = &typeid(typename ::boost::mpl::at<Bindings, P>::type);
}
const ::std::type_info*** types;
};
template<class Placeholders>
struct dynamic_vtable
{
const ::std::type_info * types[(::boost::mpl::size<Placeholders>::value)];
struct append_to_key
{
append_to_key(const std::type_info * const * t, key_type* k) : types(t), key(k) {}
template<class P>
void operator()(P)
{
key->push_back(types[(::boost::mpl::index_of<Placeholders, P>::type::value)]);
}
const std::type_info * const * types;
key_type * key;
};
template<class F>
typename F::type lookup(F*) const {
key_type key;
typedef typename ::boost::type_erasure::detail::get_placeholders<F, ::boost::mpl::set0<> >::type placeholders;
typedef typename ::boost::mpl::fold<
placeholders,
::boost::mpl::map0<>,
::boost::type_erasure::detail::counting_map_appender
>::type placeholder_map;
key.push_back(&typeid(typename ::boost::type_erasure::detail::rebind_placeholders<F, placeholder_map>::type));
::boost::mpl::for_each<placeholders>(append_to_key(types, &key));
return reinterpret_cast<typename F::type>(lookup_function_impl(key));
}
template<class Bindings>
void init()
{
const std::type_info* ptr = types;
::boost::mpl::for_each<Placeholders>(dynamic_vtable_initializer<Bindings>(ptr));
}
template<class Bindings, class Src>
struct converter
{
converter(const std::type_info**& t, const Src& s) : types(&t), src(&s) {}
template<class P>
void operator()(P)
{
*(*types)++ = &src->lookup((::boost::type_erasure::typeid_<typename ::boost::mpl::at<Bindings, P>::type>*)0)();
}
const std::type_info*** types;
const Src * src;
};
template<class Bindings, class Src>
void convert_from(const Src& src) {
const ::std::type_info** ptr = types;
::boost::mpl::for_each<Placeholders>(converter<Bindings, Src>(ptr, src));
}
};
template<class Placeholders>
struct make_dynamic_vtable
{
typedef dynamic_vtable<Placeholders> type;
};
#endif
}
}
}
#endif