Better allocator rebind support

This commit is contained in:
Daniel James
2016-10-14 09:27:40 +01:00
parent 04607dc9f3
commit da6e8e8041
3 changed files with 72 additions and 7 deletions

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@ -412,11 +412,69 @@ namespace boost { namespace unordered { namespace detail {
namespace boost { namespace unordered { namespace detail {
// TODO: Does this match std::allocator_traits<Alloc>::rebind_alloc<T>?
template <typename Alloc, typename T>
struct rebind_alloc;
#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
template <template<typename, typename...> class Alloc,
typename U, typename T, typename... Args>
struct rebind_alloc<Alloc<U, Args...>, T>
{
typedef Alloc<T, Args...> type;
};
#else
template <
template<typename> class Alloc,
typename U, typename T>
struct rebind_alloc<Alloc<U>, T>
{
typedef Alloc<T> type;
};
template <
template<typename, typename> class Alloc,
typename U, typename T,
typename A0>
struct rebind_alloc<Alloc<U, A0>, T>
{
typedef Alloc<T, A0> type;
};
template <
template<typename, typename, typename> class Alloc,
typename U, typename T,
typename A0, typename A1>
struct rebind_alloc<Alloc<U, A0, A1>, T>
{
typedef Alloc<T, A0, A1> type;
};
#endif
template <typename Alloc, typename T>
struct rebind_wrap
{
typedef typename Alloc::BOOST_NESTED_TEMPLATE rebind<T>::other type;
template <typename X>
static choice1::type test(choice1,
typename X::BOOST_NESTED_TEMPLATE rebind<T>::other* = 0);
template <typename X>
static choice2::type test(choice2, void* = 0);
enum { value = (1 == sizeof(test<Alloc>(choose()))) };
struct fallback {
template <typename U>
struct rebind {
typedef typename rebind_alloc<Alloc, T>::type other;
};
};
typedef typename boost::detail::if_true<value>::
BOOST_NESTED_TEMPLATE then<Alloc, fallback>
::type::BOOST_NESTED_TEMPLATE rebind<T>::other type;
};
# if defined(BOOST_MSVC) && BOOST_MSVC <= 1400
@ -606,7 +664,14 @@ namespace boost { namespace unordered { namespace detail {
typedef BOOST_UNORDERED_DEFAULT_TYPE(Alloc, size_type, std::size_t)
size_type;
// TODO: rebind_alloc and rebind_traits
#if !defined(BOOST_NO_CXX11_TEMPLATE_ALIASES)
template <typename T>
using rebind_alloc = typename rebind_wrap<Alloc, T>::type;
template <typename T>
using rebind_traits =
boost::unordered::detail::allocator_traits<rebind_alloc<T> >;
#endif
static pointer allocate(Alloc& a, size_type n)
{ return a.allocate(n); }

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@ -201,9 +201,9 @@ namespace test
public move_allocator_base<Flags>,
Flags
{
template <typename U> struct rebind {
typedef cxx11_allocator<U, Flags> other;
};
//template <typename U> struct rebind {
// typedef cxx11_allocator<U, Flags> other;
//};
explicit cxx11_allocator(int t = 0)
: cxx11_allocator_base<T>(t)

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@ -447,7 +447,7 @@ namespace minimal
{
public:
typedef T value_type;
template <class U> struct rebind { typedef cxx11_allocator<U> other; };
//template <class U> struct rebind { typedef cxx11_allocator<U> other; };
cxx11_allocator() {}
template <class Y> cxx11_allocator(cxx11_allocator<Y> const&) {}