263 lines
6.3 KiB
C++
263 lines
6.3 KiB
C++
/* Copyright 2003-2015 Joaquin M Lopez Munoz.
|
|
* 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)
|
|
*
|
|
* See http://www.boost.org/libs/multi_index for library home page.
|
|
*/
|
|
|
|
#ifndef BOOST_MULTI_INDEX_MEMBER_HPP
|
|
#define BOOST_MULTI_INDEX_MEMBER_HPP
|
|
|
|
#if defined(_MSC_VER)
|
|
#pragma once
|
|
#endif
|
|
|
|
#include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
|
|
#include <boost/mpl/if.hpp>
|
|
#include <boost/type_traits/is_const.hpp>
|
|
#include <boost/utility/enable_if.hpp>
|
|
#include <cstddef>
|
|
|
|
#if !defined(BOOST_NO_SFINAE)
|
|
#include <boost/type_traits/is_convertible.hpp>
|
|
#endif
|
|
|
|
namespace boost{
|
|
|
|
template<class T> class reference_wrapper; /* fwd decl. */
|
|
|
|
namespace multi_index{
|
|
|
|
namespace detail{
|
|
|
|
/* member is a read/write key extractor for accessing a given
|
|
* member of a class.
|
|
* Additionally, member is overloaded to support referece_wrappers
|
|
* of T and "chained pointers" to T's. By chained pointer to T we mean
|
|
* a type P such that, given a p of Type P
|
|
* *...n...*x is convertible to T&, for some n>=1.
|
|
* Examples of chained pointers are raw and smart pointers, iterators and
|
|
* arbitrary combinations of these (vg. T** or unique_ptr<T*>.)
|
|
*/
|
|
|
|
template<class Class,typename Type,Type Class::*PtrToMember>
|
|
struct const_member_base
|
|
{
|
|
typedef Type result_type;
|
|
|
|
template<typename ChainedPtr>
|
|
|
|
#if !defined(BOOST_NO_SFINAE)
|
|
typename disable_if<
|
|
is_convertible<const ChainedPtr&,const Class&>,Type&>::type
|
|
#else
|
|
Type&
|
|
#endif
|
|
|
|
operator()(const ChainedPtr& x)const
|
|
{
|
|
return operator()(*x);
|
|
}
|
|
|
|
Type& operator()(const Class& x)const
|
|
{
|
|
return x.*PtrToMember;
|
|
}
|
|
|
|
Type& operator()(const reference_wrapper<const Class>& x)const
|
|
{
|
|
return operator()(x.get());
|
|
}
|
|
|
|
Type& operator()(const reference_wrapper<Class>& x)const
|
|
{
|
|
return operator()(x.get());
|
|
}
|
|
};
|
|
|
|
template<class Class,typename Type,Type Class::*PtrToMember>
|
|
struct non_const_member_base
|
|
{
|
|
typedef Type result_type;
|
|
|
|
template<typename ChainedPtr>
|
|
|
|
#if !defined(BOOST_NO_SFINAE)
|
|
typename disable_if<
|
|
is_convertible<const ChainedPtr&,const Class&>,Type&>::type
|
|
#else
|
|
Type&
|
|
#endif
|
|
|
|
operator()(const ChainedPtr& x)const
|
|
{
|
|
return operator()(*x);
|
|
}
|
|
|
|
const Type& operator()(const Class& x)const
|
|
{
|
|
return x.*PtrToMember;
|
|
}
|
|
|
|
Type& operator()(Class& x)const
|
|
{
|
|
return x.*PtrToMember;
|
|
}
|
|
|
|
const Type& operator()(const reference_wrapper<const Class>& x)const
|
|
{
|
|
return operator()(x.get());
|
|
}
|
|
|
|
Type& operator()(const reference_wrapper<Class>& x)const
|
|
{
|
|
return operator()(x.get());
|
|
}
|
|
};
|
|
|
|
} /* namespace multi_index::detail */
|
|
|
|
template<class Class,typename Type,Type Class::*PtrToMember>
|
|
struct member:
|
|
mpl::if_c<
|
|
is_const<Type>::value,
|
|
detail::const_member_base<Class,Type,PtrToMember>,
|
|
detail::non_const_member_base<Class,Type,PtrToMember>
|
|
>::type
|
|
{
|
|
};
|
|
|
|
namespace detail{
|
|
|
|
/* MSVC++ 6.0 does not support properly pointers to members as
|
|
* non-type template arguments, as reported in
|
|
* http://support.microsoft.com/default.aspx?scid=kb;EN-US;249045
|
|
* A similar problem (though not identical) is shown by MSVC++ 7.0.
|
|
* We provide an alternative to member<> accepting offsets instead
|
|
* of pointers to members. This happens to work even for non-POD
|
|
* types (although the standard forbids use of offsetof on these),
|
|
* so it serves as a workaround in this compiler for all practical
|
|
* purposes.
|
|
* Surprisingly enough, other compilers, like Intel C++ 7.0/7.1 and
|
|
* Visual Age 6.0, have similar bugs. This replacement of member<>
|
|
* can be used for them too.
|
|
*
|
|
* Support for such old compilers is dropped and
|
|
* [non_]const_member_offset_base is deprecated.
|
|
*/
|
|
|
|
template<class Class,typename Type,std::size_t OffsetOfMember>
|
|
struct const_member_offset_base
|
|
{
|
|
typedef Type result_type;
|
|
|
|
template<typename ChainedPtr>
|
|
|
|
#if !defined(BOOST_NO_SFINAE)
|
|
typename disable_if<
|
|
is_convertible<const ChainedPtr&,const Class&>,Type&>::type
|
|
#else
|
|
Type&
|
|
#endif
|
|
|
|
operator()(const ChainedPtr& x)const
|
|
{
|
|
return operator()(*x);
|
|
}
|
|
|
|
Type& operator()(const Class& x)const
|
|
{
|
|
return *static_cast<const Type*>(
|
|
static_cast<const void*>(
|
|
static_cast<const char*>(
|
|
static_cast<const void *>(&x))+OffsetOfMember));
|
|
}
|
|
|
|
Type& operator()(const reference_wrapper<const Class>& x)const
|
|
{
|
|
return operator()(x.get());
|
|
}
|
|
|
|
Type& operator()(const reference_wrapper<Class>& x)const
|
|
{
|
|
return operator()(x.get());
|
|
}
|
|
};
|
|
|
|
template<class Class,typename Type,std::size_t OffsetOfMember>
|
|
struct non_const_member_offset_base
|
|
{
|
|
typedef Type result_type;
|
|
|
|
template<typename ChainedPtr>
|
|
|
|
#if !defined(BOOST_NO_SFINAE)
|
|
typename disable_if<
|
|
is_convertible<const ChainedPtr&,const Class&>,Type&>::type
|
|
#else
|
|
Type&
|
|
#endif
|
|
|
|
operator()(const ChainedPtr& x)const
|
|
{
|
|
return operator()(*x);
|
|
}
|
|
|
|
const Type& operator()(const Class& x)const
|
|
{
|
|
return *static_cast<const Type*>(
|
|
static_cast<const void*>(
|
|
static_cast<const char*>(
|
|
static_cast<const void *>(&x))+OffsetOfMember));
|
|
}
|
|
|
|
Type& operator()(Class& x)const
|
|
{
|
|
return *static_cast<Type*>(
|
|
static_cast<void*>(
|
|
static_cast<char*>(static_cast<void *>(&x))+OffsetOfMember));
|
|
}
|
|
|
|
const Type& operator()(const reference_wrapper<const Class>& x)const
|
|
{
|
|
return operator()(x.get());
|
|
}
|
|
|
|
Type& operator()(const reference_wrapper<Class>& x)const
|
|
{
|
|
return operator()(x.get());
|
|
}
|
|
};
|
|
|
|
} /* namespace multi_index::detail */
|
|
|
|
template<class Class,typename Type,std::size_t OffsetOfMember>
|
|
struct member_offset:
|
|
mpl::if_c<
|
|
is_const<Type>::value,
|
|
detail::const_member_offset_base<Class,Type,OffsetOfMember>,
|
|
detail::non_const_member_offset_base<Class,Type,OffsetOfMember>
|
|
>::type
|
|
{
|
|
};
|
|
|
|
/* BOOST_MULTI_INDEX_MEMBER resolves to member in the normal cases,
|
|
* and to member_offset as a workaround in those defective compilers for
|
|
* which BOOST_NO_POINTER_TO_MEMBER_TEMPLATE_PARAMETERS is defined.
|
|
*/
|
|
|
|
#if defined(BOOST_NO_POINTER_TO_MEMBER_TEMPLATE_PARAMETERS)
|
|
#define BOOST_MULTI_INDEX_MEMBER(Class,Type,MemberName) \
|
|
::boost::multi_index::member_offset< Class,Type,offsetof(Class,MemberName) >
|
|
#else
|
|
#define BOOST_MULTI_INDEX_MEMBER(Class,Type,MemberName) \
|
|
::boost::multi_index::member< Class,Type,&Class::MemberName >
|
|
#endif
|
|
|
|
} /* namespace multi_index */
|
|
|
|
} /* namespace boost */
|
|
|
|
#endif
|