159 lines
5.3 KiB
C++
159 lines
5.3 KiB
C++
// boost utility/base_from_member.hpp header file --------------------------//
|
|
|
|
// Copyright 2001, 2003, 2004, 2012 Daryle Walker. Use, modification, and
|
|
// distribution are subject to the Boost Software License, Version 1.0. (See
|
|
// accompanying file LICENSE_1_0.txt or a copy at
|
|
// <http://www.boost.org/LICENSE_1_0.txt>.)
|
|
|
|
// See <http://www.boost.org/libs/utility/> for the library's home page.
|
|
|
|
#ifndef BOOST_UTILITY_BASE_FROM_MEMBER_HPP
|
|
#define BOOST_UTILITY_BASE_FROM_MEMBER_HPP
|
|
|
|
#include <boost/config.hpp>
|
|
#include <boost/preprocessor/arithmetic/inc.hpp>
|
|
#include <boost/preprocessor/repetition/enum_binary_params.hpp>
|
|
#include <boost/preprocessor/repetition/enum_params.hpp>
|
|
#include <boost/preprocessor/repetition/repeat_from_to.hpp>
|
|
#include <boost/type_traits/is_same.hpp>
|
|
#include <boost/type_traits/remove_cv.hpp>
|
|
#include <boost/type_traits/remove_reference.hpp>
|
|
#include <boost/utility/enable_if.hpp>
|
|
|
|
|
|
// Base-from-member arity configuration macro ------------------------------//
|
|
|
|
// The following macro determines how many arguments will be in the largest
|
|
// constructor template of base_from_member. Constructor templates will be
|
|
// generated from one argument to this maximum. Code from other files can read
|
|
// this number if they need to always match the exact maximum base_from_member
|
|
// uses. The maximum constructor length can be changed by overriding the
|
|
// #defined constant. Make sure to apply the override, if any, for all source
|
|
// files during project compiling for consistency.
|
|
|
|
// Contributed by Jonathan Turkanis
|
|
|
|
#ifndef BOOST_BASE_FROM_MEMBER_MAX_ARITY
|
|
#define BOOST_BASE_FROM_MEMBER_MAX_ARITY 10
|
|
#endif
|
|
|
|
|
|
// An iteration of a constructor template for base_from_member -------------//
|
|
|
|
// A macro that should expand to:
|
|
// template < typename T1, ..., typename Tn >
|
|
// base_from_member( T1 x1, ..., Tn xn )
|
|
// : member( x1, ..., xn )
|
|
// {}
|
|
// This macro should only persist within this file.
|
|
|
|
#define BOOST_PRIVATE_CTR_DEF( z, n, data ) \
|
|
template < BOOST_PP_ENUM_PARAMS(n, typename T) > \
|
|
explicit base_from_member( BOOST_PP_ENUM_BINARY_PARAMS(n, T, x) ) \
|
|
: member( BOOST_PP_ENUM_PARAMS(n, x) ) \
|
|
{} \
|
|
/**/
|
|
|
|
|
|
namespace boost
|
|
{
|
|
|
|
namespace detail
|
|
{
|
|
|
|
// Type-unmarking class template -------------------------------------------//
|
|
|
|
// Type-trait to get the raw type, i.e. the type without top-level reference nor
|
|
// cv-qualification, from a type expression. Mainly for function arguments, any
|
|
// reference part is stripped first.
|
|
|
|
// Contributed by Daryle Walker
|
|
|
|
template < typename T >
|
|
struct remove_cv_ref
|
|
{
|
|
typedef typename ::boost::remove_cv<typename
|
|
::boost::remove_reference<T>::type>::type type;
|
|
|
|
}; // boost::detail::remove_cv_ref
|
|
|
|
// Unmarked-type comparison class template ---------------------------------//
|
|
|
|
// Type-trait to check if two type expressions have the same raw type.
|
|
|
|
// Contributed by Daryle Walker, based on a work-around by Luc Danton
|
|
|
|
template < typename T, typename U >
|
|
struct is_related
|
|
: public ::boost::is_same<
|
|
typename ::boost::detail::remove_cv_ref<T>::type,
|
|
typename ::boost::detail::remove_cv_ref<U>::type >
|
|
{};
|
|
|
|
// Enable-if-on-unidentical-unmarked-type class template -------------------//
|
|
|
|
// Enable-if on the first two type expressions NOT having the same raw type.
|
|
|
|
// Contributed by Daryle Walker, based on a work-around by Luc Danton
|
|
|
|
#ifndef BOOST_NO_CXX11_VARIADIC_TEMPLATES
|
|
template<typename ...T>
|
|
struct enable_if_unrelated
|
|
: public ::boost::enable_if_c<true>
|
|
{};
|
|
|
|
template<typename T, typename U, typename ...U2>
|
|
struct enable_if_unrelated<T, U, U2...>
|
|
: public ::boost::disable_if< ::boost::detail::is_related<T, U> >
|
|
{};
|
|
#endif
|
|
|
|
} // namespace boost::detail
|
|
|
|
|
|
// Base-from-member class template -----------------------------------------//
|
|
|
|
// Helper to initialize a base object so a derived class can use this
|
|
// object in the initialization of another base class. Used by
|
|
// Dietmar Kuehl from ideas by Ron Klatcho to solve the problem of a
|
|
// base class needing to be initialized by a member.
|
|
|
|
// Contributed by Daryle Walker
|
|
|
|
template < typename MemberType, int UniqueID = 0 >
|
|
class base_from_member
|
|
{
|
|
protected:
|
|
MemberType member;
|
|
|
|
#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && \
|
|
!defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && \
|
|
!defined(BOOST_NO_CXX11_FUNCTION_TEMPLATE_DEFAULT_ARGS) && \
|
|
!(defined(__GNUC__) && (__GNUC__ == 4) && (__GNUC_MINOR__ < 4))
|
|
template <typename ...T, typename EnableIf = typename
|
|
::boost::detail::enable_if_unrelated<base_from_member, T...>::type>
|
|
explicit BOOST_CONSTEXPR base_from_member( T&& ...x )
|
|
BOOST_NOEXCEPT_IF( BOOST_NOEXCEPT_EXPR(::new ((void*) 0) MemberType(
|
|
static_cast<T&&>(x)... )) ) // no std::is_nothrow_constructible...
|
|
: member( static_cast<T&&>(x)... ) // ...nor std::forward needed
|
|
{}
|
|
#else
|
|
base_from_member()
|
|
: member()
|
|
{}
|
|
|
|
BOOST_PP_REPEAT_FROM_TO( 1, BOOST_PP_INC(BOOST_BASE_FROM_MEMBER_MAX_ARITY),
|
|
BOOST_PRIVATE_CTR_DEF, _ )
|
|
#endif
|
|
|
|
}; // boost::base_from_member
|
|
|
|
} // namespace boost
|
|
|
|
|
|
// Undo any private macros
|
|
#undef BOOST_PRIVATE_CTR_DEF
|
|
|
|
|
|
#endif // BOOST_UTILITY_BASE_FROM_MEMBER_HPP
|