Unordered: More portable allocator_traits.

[SVN r74067]
This commit is contained in:
Daniel James
2011-08-26 08:11:46 +00:00
parent cfd52c8f38
commit 099a893678
6 changed files with 317 additions and 61 deletions

View File

@@ -5,8 +5,8 @@
// 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)
//
// Written by Daniel James using some code from Pablo Halpern's
// allocator traits implementation.
// Allocator traits written by Daniel James based on Pablo Halpern's
// implementation.
#ifndef BOOST_UNORDERED_DETAIL_ALLOCATOR_UTILITIES_HPP_INCLUDED
#define BOOST_UNORDERED_DETAIL_ALLOCATOR_UTILITIES_HPP_INCLUDED
@@ -18,6 +18,7 @@
#include <boost/config.hpp>
#include <boost/detail/select_type.hpp>
#include <boost/utility/enable_if.hpp>
#include <boost/preprocessor/cat.hpp>
#if (defined(BOOST_NO_STD_ALLOCATOR) || defined(BOOST_DINKUMWARE_STDLIB)) \
&& !defined(__BORLANDC__)
@@ -81,38 +82,39 @@ namespace boost { namespace unordered { namespace detail {
};
# endif
struct convertible_from_anything
{
template<typename T> convertible_from_anything(T const&);
};
template <typename T> T& make();
struct choice9 { typedef char (&type)[9]; };
struct choice8 : choice9 { typedef char (&type)[8]; };
struct choice7 : choice8 { typedef char (&type)[7]; };
struct choice6 : choice7 { typedef char (&type)[6]; };
struct choice5 : choice6 { typedef char (&type)[5]; };
struct choice4 : choice5 { typedef char (&type)[4]; };
struct choice3 : choice4 { typedef char (&type)[3]; };
struct choice2 : choice3 { typedef char (&type)[2]; };
struct choice1 : choice2 { typedef char (&type)[1]; };
choice1 choose();
typedef char (&no_type)[1];
typedef char (&yes_type)[2];
template <typename T> struct sfinae {
typedef yes_type type;
};
// Infrastructure for providing a default type for Tp::tname if absent.
#define BOOST_DEFAULT_TYPE_TMPLT(tname) \
template <typename Tp, typename Default> \
struct default_type_ ## tname { \
template <typename T> \
static BOOST_DEDUCED_TYPENAME sfinae< \
BOOST_DEDUCED_TYPENAME T::tname>::type test(int); \
template <typename T> \
static no_type test(long); \
\
enum { value = sizeof(test<Tp>(0)) == sizeof(yes_type) }; \
template <typename X> \
static choice1::type test(choice1, \
BOOST_DEDUCED_TYPENAME X::tname* = 0); \
\
template <typename X> \
static choice2::type test(choice2, void* = 0); \
\
struct DefaultWrap { typedef Default tname; }; \
\
enum { value = (1 == sizeof(test<Tp>(choose()))) }; \
\
typedef BOOST_DEDUCED_TYPENAME \
boost::detail::if_true<value>:: \
BOOST_NESTED_TEMPLATE then<Tp, DefaultWrap> \
::type::tname type; \
}
#define BOOST_DEFAULT_TYPE(T,tname, arg) \
BOOST_DEDUCED_TYPENAME default_type_ ## tname<T, arg>::type
@@ -127,47 +129,62 @@ namespace boost { namespace unordered { namespace detail {
BOOST_DEFAULT_TYPE_TMPLT(propagate_on_container_swap);
#if !defined(BOOST_NO_SFINAE_EXPR) || BOOST_WORKAROUND(BOOST_MSVC, >= 1500)
// Specialization is only needed for Visual C++. Without it SFINAE doesn't
// kick in.
template <unsigned int>
struct expr_sfinae;
template <>
struct expr_sfinae<sizeof(yes_type)> {
typedef yes_type type;
};
template <typename T, unsigned int> struct expr_test;
template <typename T> struct expr_test<T, sizeof(char)> : T {};
template <typename U> static char for_expr_test(U const&);
#define BOOST_UNORDERED_CHECK_EXPRESSION(count, result, expression) \
template <typename U> \
static typename expr_test< \
BOOST_PP_CAT(choice, result), \
sizeof(for_expr_test(((expression), 0)))>::type test( \
BOOST_PP_CAT(choice, count))
#define BOOST_UNORDERED_DEFAULT_EXPRESSION(count, result) \
template <typename U> \
static BOOST_PP_CAT(choice, result)::type test( \
BOOST_PP_CAT(choice, count));
template <typename T>
struct has_select_on_container_copy_construction
{
// This needs to be a template for Visual C++.
template <typename T2>
static yes_type to_yes_type(const T2&);
template <typename T2>
static typename expr_sfinae<sizeof(to_yes_type(
((T2 const*)0)->select_on_container_copy_construction()
))>::type check(T2*);
static no_type check(void*);
BOOST_UNORDERED_CHECK_EXPRESSION(1, 1, make<U const>().select_on_container_copy_construction());
BOOST_UNORDERED_DEFAULT_EXPRESSION(2, 2);
enum { value = sizeof(check((T*) 0)) == sizeof(yes_type) };
enum { value = sizeof(test<T>(choose())) == sizeof(choice1::type) };
};
#else
template <typename T> struct identity { typedef T type; };
#define BOOST_UNORDERED_CHECK_MEMBER(count, result, name, member) \
\
typedef typename identity<member>::type BOOST_PP_CAT(check, count); \
\
template <BOOST_PP_CAT(check, count) e> \
struct BOOST_PP_CAT(test, count) { \
typedef void* type; \
}; \
\
template <class U> static BOOST_PP_CAT(choice, result)::type \
test(BOOST_PP_CAT(choice, count), \
typename BOOST_PP_CAT(test, count)< \
&U::name>::type = 0)
#define BOOST_UNORDERED_DEFAULT_MEMBER(count, result) \
template <class U> static BOOST_PP_CAT(choice, result)::type \
test(BOOST_PP_CAT(choice, count), void* = 0)
template <typename T>
struct has_select_on_container_copy_construction
{
typedef T (T::*SelectFunc)() const;
template <SelectFunc e> struct sfinae { typedef yes_type type; };
template <class U>
static typename sfinae<&U::select_on_container_copy_construction>::type
test(int);
template <class U>
static no_type test(...);
BOOST_UNORDERED_CHECK_MEMBER(1, 1, select_on_container_copy_construction, T (T::*)() const);
BOOST_UNORDERED_DEFAULT_MEMBER(2, 2);
enum { value = sizeof(test<T>(1)) == sizeof(yes_type) };
enum { value = sizeof(test<T>(choose())) == sizeof(choice1::type) };
};
#endif