wpi::memory Namespace Reference

Memory namespace. More...

Namespaces
namespace	detail
namespace	literals
	Literals namespace.
namespace	traits_detail

Classes
class	aligned_allocator
	A RawAllocator adapter that ensures a minimum alignment. More...
struct	allocate_shared_node_size
	The node size required by allocate_shared. More...
class	allocator_adapter
	An alias template for allocator_storage using the direct_storage policy without a mutex. More...
class	allocator_deallocator
	A deleter class that deallocates the memory through a specified RawAllocator. More...
class	allocator_deallocator< Type[], RawAllocator >
	Specialization of allocator_deallocator for array types. More...
class	allocator_deleter
	Similar to allocator_deallocator but calls the destructors of the object. More...
class	allocator_deleter< Type[], RawAllocator >
	Specialization of allocator_deleter for array types. More...
struct	allocator_info
	Contains information about an allocator. More...
struct	allocator_is_raw_allocator
	Traits class that checks whether or not a standard Allocator can be used as RawAllocator. More...
struct	allocator_is_raw_allocator< std::allocator< T > >
	Specialization of allocator_is_raw_allocator that allows std::allocator again. More...
class	allocator_polymorphic_deallocator
	A deleter class that deallocates the memory of a derived type through a specified RawAllocator. More...
class	allocator_polymorphic_deleter
	Similar to allocator_polymorphic_deallocator but calls the destructors of the object. More...
class	allocator_reference
	An alias template for allocator_storage using the reference_storage policy. More...
class	allocator_storage
	A RawAllocator that stores another allocator. More...
class	allocator_traits
	The default specialization of the allocator_traits for a RawAllocator. More...
class	allocator_traits< iteration_allocator< N, BlockAllocator > >
	Specialization of the allocator_traits for iteration_allocator. More...
class	allocator_traits< memory_pool< PoolType, ImplRawAllocator > >
	Specialization of the allocator_traits for memory_pool classes. More...
class	allocator_traits< memory_pool_collection< Pool, BucketDist, RawAllocator > >
	Specialization of the allocator_traits for memory_pool_collection classes. More...
class	allocator_traits< memory_stack< BlockAllocator > >
	Specialization of the allocator_traits for memory_stack classes. More...
class	allocator_traits< temporary_allocator >
	Specialization of the allocator_traits for temporary_allocator classes. More...
struct	any_allocator
	Tag type that enables type-erasure in reference_storage. More...
class	any_std_allocator
	An alias template for std_allocator using a type-erased RawAllocator. More...
struct	array_pool
	Tag type defining a memory pool optimized for arrays. More...
class	bad_alignment
	The exception class thrown when the alignment exceeds the supported maximum, i.e. More...
class	bad_allocation_size
	The exception class thrown when an allocation size is bigger than the supported maximum. More...
class	bad_array_size
	The exception class thrown when the array size exceeds the supported maximum, i.e. More...
class	bad_node_size
	The exception class thrown when the node size exceeds the supported maximum, i.e. More...
class	binary_segregator
	A RawAllocator that either uses the Segregatable or the other RawAllocator. More...
class	bucket_allocator
	An alias for memory_pool_collection using the identity_buckets policy and a PoolType defaulting to node_pool. More...
class	composable_allocator_traits
	The default specialization of the composable_allocator_traits for a ComposableAllocator. More...
class	composable_allocator_traits< iteration_allocator< N, BlockAllocator > >
	Specialization of the composable_allocator_traits for iteration_allocator classes. More...
class	composable_allocator_traits< memory_pool< PoolType, BlockOrRawAllocator > >
	Specialization of the composable_allocator_traits for memory_pool classes. More...
class	composable_allocator_traits< memory_pool_collection< Pool, BucketDist, RawAllocator > >
	Specialization of the composable_allocator_traits for memory_pool_collection classes. More...
class	composable_allocator_traits< memory_stack< BlockAllocator > >
	Specialization of the composable_allocator_traits for memory_stack classes. More...
class	deeply_tracked_allocator
	A tracked_allocator that has rebound any BlockAllocator to the corresponding deeply_tracked_block_allocator. More...
class	deque
	Alias template for an STL container that uses a certain RawAllocator. More...
class	deque_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
class	direct_storage
	A StoragePolicy that stores the allocator directly. More...
class	double_frame_allocator
	An alias for iteration_allocator for two iterations. More...
class	fallback_allocator
	A RawAllocator with a fallback. More...
class	fixed_block_allocator
	A BlockAllocator that allows only one block allocation. More...
class	forward_list
	Alias template for an STL container that uses a certain RawAllocator. More...
struct	forward_list_node_size
	Contains the node size of a node based STL container with a specific type. More...
class	forward_list_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
class	growing_block_allocator
	A BlockAllocator that uses a given RawAllocator for allocating the blocks. More...
struct	identity_buckets
	A BucketDistribution for memory_pool_collection defining that there is a bucket, i.e. More...
struct	is_block_allocator
	Traits that check whether a type models concept BlockAllocator. More...
struct	is_composable_allocator
	Traits that check whether a type models concept ComposableAllocator. More...
struct	is_raw_allocator
	Traits that check whether a type models concept RawAllocator. More...
struct	is_shared_allocator
	Specifies whether or not a RawAllocator has shared semantics. More...
struct	is_shared_allocator< joint_allocator >
	Specialization of is_shared_allocator to mark joint_allocator as shared. More...
struct	is_shared_allocator< memory_resource_allocator >
	Specialization of is_shared_allocator to mark memory_resource_allocator as shared. More...
struct	is_thread_safe_allocator
	Specifies whether or not a RawAllocator is thread safe as-is. More...
struct	is_thread_safe_allocator< joint_allocator >
	Specialization of is_thread_safe_allocator to mark joint_allocator as thread safe. More...
class	iteration_allocator
	A stateful RawAllocator that is designed for allocations in a loop. More...
class	joint
	Tag type that can't be created. More...
class	joint_allocator
	A RawAllocator that uses the additional joint memory for its allocation. More...
class	joint_array
	A zero overhead dynamic array using joint memory. More...
class	joint_ptr
	A pointer to an object where all allocations are joint. More...
struct	joint_size
	Tag type to make the joint size more explicit. More...
class	joint_type
	CRTP base class for all objects that want to use joint memory. More...
class	list
	Alias template for an STL container that uses a certain RawAllocator. More...
struct	list_node_size
	Contains the node size of a node based STL container with a specific type. More...
class	list_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
struct	log2_buckets
	A BucketDistribution for memory_pool_collection defining that there is a bucket, i.e. More...
class	map
	Alias template for an STL container that uses a certain RawAllocator. More...
struct	map_node_size
	Contains the node size of a node based STL container with a specific type. More...
class	map_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
class	memory_arena
	A memory arena that manages huge memory blocks for a higher-level allocator. More...
struct	memory_block
	A memory block. More...
class	memory_pool
	A stateful RawAllocator that manages nodes of fixed size. More...
class	memory_pool_collection
	A stateful RawAllocator that behaves as a collection of multiple memory_pool objects. More...
class	memory_resource
	The memory_resource abstract base class used in the implementation. More...
class	memory_resource_adapter
	Wraps a RawAllocator and makes it a memory_resource. More...
class	memory_resource_allocator
	Wraps a memory_resource and makes it a RawAllocator. More...
class	memory_stack
	A stateful RawAllocator that provides stack-like (LIFO) allocations. More...
class	memory_stack_raii_unwind
	Simple utility that automatically unwinds a Stack to a previously saved location. More...
class	multimap
	Alias template for an STL container that uses a certain RawAllocator. More...
struct	multimap_node_size
	Contains the node size of a node based STL container with a specific type. More...
class	multimap_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
class	multiset
	Alias template for an STL container that uses a certain RawAllocator. More...
struct	multiset_node_size
	Contains the node size of a node based STL container with a specific type. More...
class	multiset_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
struct	no_mutex
	A dummy Mutex class that does not lock anything. More...
struct	node_pool
	Tag type defining a memory pool optimized for nodes. More...
class	null_allocator
	A composable RawAllocator that will always fail. More...
class	out_of_fixed_memory
	A special case of out_of_memory errors thrown when a low-level allocator with a fixed size runs out of memory. More...
class	out_of_memory
	The exception class thrown when a low level allocator runs out of memory. More...
class	priority_queue
	Alias template for an STL container that uses a certain RawAllocator. More...
class	priority_queue_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
struct	propagation_traits
	Controls the propagation of a std_allocator for a certain RawAllocator. More...
struct	propagation_traits< joint_allocator >
	Specialization of the propagation_traits for the joint_allocator. More...
class	queue
	Alias template for an STL container that uses a certain RawAllocator. More...
class	queue_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
class	reference_storage
	A StoragePolicy that stores a reference to an allocator. More...
class	reference_storage< any_allocator >
	Specialization of the class template reference_storage that is type-erased. More...
class	segregator
	Creates multiple nested binary_segregator. More...
struct	segregator_size
	The number of Segregatable a segregator has. More...
class	set
	Alias template for an STL container that uses a certain RawAllocator. More...
struct	set_node_size
	Contains the node size of a node based STL container with a specific type. More...
class	set_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
struct	shared_ptr_node_size
	Contains the node size of a node based STL container with a specific type. More...
struct	small_node_pool
	Tag type defining a memory pool optimized for small nodes. More...
class	stack
	Alias template for an STL container that uses a certain RawAllocator. More...
class	stack_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
class	static_allocator
	A stateful RawAllocator that uses a fixed sized storage for the allocations. More...
struct	static_allocator_storage
	Storage for a static_allocator. More...
class	static_block_allocator
	A BlockAllocator that allocates the blocks from a fixed size storage. More...
class	std_allocator
	Wraps a RawAllocator and makes it a "normal" Allocator. More...
class	string
	Alias template for an STL container that uses a certain RawAllocator. More...
class	temporary_allocator
	A stateful RawAllocator that handles temporary allocations. More...
class	temporary_stack
	A wrapper around the memory_stack that is used by the temporary_allocator. More...
class	temporary_stack_initializer
	Manually takes care of the lifetime of the per-thread temporary_stack. More...
class	thread_safe_allocator
	An alias template for allocator_storage using the direct_storage policy with a mutex. More...
class	threshold_segregatable
	A Segregatable that allocates until a maximum size. More...
class	tracked_allocator
	A RawAllocator adapter that tracks another allocator using a tracker. More...
class	tracked_block_allocator
	A BlockAllocator adapter that tracks another allocator using a tracker. More...
class	unique_base_ptr
	A std::unique_ptr that deletes using a RawAllocator and allows polymorphic types. More...
class	unique_ptr
	A std::unique_ptr that deletes using a RawAllocator. More...
class	unordered_map
	Alias template for an STL container that uses a certain RawAllocator. More...
struct	unordered_map_node_size
	Contains the node size of a node based STL container with a specific type. More...
class	unordered_map_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
class	unordered_multimap
	Alias template for an STL container that uses a certain RawAllocator. More...
struct	unordered_multimap_node_size
	Contains the node size of a node based STL container with a specific type. More...
class	unordered_multimap_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
class	unordered_multiset
	Alias template for an STL container that uses a certain RawAllocator. More...
struct	unordered_multiset_node_size
	Contains the node size of a node based STL container with a specific type. More...
class	unordered_multiset_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
class	unordered_set
	Alias template for an STL container that uses a certain RawAllocator. More...
struct	unordered_set_node_size
	Contains the node size of a node based STL container with a specific type. More...
class	unordered_set_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
class	vector
	Alias template for an STL container that uses a certain RawAllocator. More...
class	vector_scoped_alloc
	Same as above but uses std::scoped_allocator_adaptor so the allocator is inherited by all nested containers. More...
class	virtual_block_allocator
	A BlockAllocator that reserves virtual memory and commits it part by part. More...
class	virtual_memory_allocator
	A stateless RawAllocator that allocates memory using the virtual memory allocation functions. More...

Typedefs
using	heap_allocator
	A stateless RawAllocator that allocates memory from the heap.
template<class Tracker , class BlockOrRawAllocator >
using	deeply_tracked_block_allocator
	Similar to tracked_block_allocator, but shares the tracker with the higher level allocator.
using	any_reference_storage = reference_storage<any_allocator>
	An alias for the reference_storage specialization using type-erasure.
using	any_allocator_reference = allocator_storage<any_reference_storage, no_mutex>
	An alias for allocator_storage using the any_reference_storage.
using	default_allocator = implementation_defined
	The default RawAllocator that will be used as BlockAllocator in memory arenas.
using	new_allocator
	A stateless RawAllocator that allocates memory using (nothrow) operator new.
using	malloc_allocator
	A stateless RawAllocator that allocates memory using std::malloc().
template<class BlockOrRawAllocator , template< typename... > class BlockAllocator = detail::default_block_wrapper>
using	make_block_allocator_t
	Takes either a BlockAllocator or a RawAllocator.
using	leak_handler = void (*)(const allocator_info& info, std::ptrdiff_t amount)
	The type of the handler called when a memory leak is detected.
using	invalid_pointer_handler = void (*)(const allocator_info& info, const void* ptr)
	The type of the handler called when an invalid pointer is passed to a deallocation function.
using	buffer_overflow_handler
	The type of the handler called when a buffer under/overflow is detected.

Enumerations
enum class	debug_magic : unsigned char {   debug_magic::internal_memory = 0xAB , debug_magic::internal_freed_memory = 0xFB , debug_magic::new_memory = 0xCD , debug_magic::freed_memory = 0xDD ,   debug_magic::alignment_memory = 0xED , debug_magic::fence_memory = 0xFD }
	The magic values that are used for debug filling. More...

Functions
void *	heap_alloc (std::size_t size) noexcept
	Allocates heap memory.
void	heap_dealloc (void *ptr, std::size_t size) noexcept
	Deallocates heap memory.
temporary_stack &	get_temporary_stack (std::size_t initial_size=temporary_stack_initializer::default_stack_size)
template<typename T , class RawAllocator , typename... Args>
auto	allocate_unique (RawAllocator &&alloc, Args &&... args) ->
	Creates a std::unique_ptr using a RawAllocator for the allocation.
template<typename T , class RawAllocator , typename... Args>
auto	allocate_unique (any_allocator, RawAllocator &&alloc, Args &&... args) ->
	Creates a std::unique_ptr using a type-erased RawAllocator for the allocation.
template<typename T , class RawAllocator >
auto	allocate_unique (RawAllocator &&alloc, std::size_t size) ->
	Creates a std::unique_ptr owning an array using a RawAllocator for the allocation.
template<typename T , class RawAllocator >
auto	allocate_unique (any_allocator, RawAllocator &&alloc, std::size_t size) ->
	Creates a std::unique_ptr owning an array using a type-erased RawAllocator for the allocation.
template<typename T , class RawAllocator , typename... Args>
std::shared_ptr< T >	allocate_shared (RawAllocator &&alloc, Args &&... args)
	Creates a std::shared_ptr using a RawAllocator for the allocation.
std::size_t	get_virtual_memory_page_size () noexcept
void *	virtual_memory_reserve (std::size_t no_pages) noexcept
	Reserves virtual memory.
void	virtual_memory_release (void *pages, std::size_t no_pages) noexcept
	Releases reserved virtual memory.
void *	virtual_memory_commit (void *memory, std::size_t no_pages) noexcept
	Commits reserved virtual memory.
void	virtual_memory_decommit (void *memory, std::size_t no_pages) noexcept
	Decommits commited virtual memory.
template<class RawAllocator >
threshold_segregatable< typename std::decay< RawAllocator >::type >	threshold (std::size_t max_size, RawAllocator &&alloc)
leak_handler	set_leak_handler (leak_handler h)
	Exchanges the leak_handler.
leak_handler	get_leak_handler ()
	Returns the leak_handler.
invalid_pointer_handler	set_invalid_pointer_handler (invalid_pointer_handler h)
	Exchanges the invalid_pointer_handler.
invalid_pointer_handler	get_invalid_pointer_handler ()
	Returns the invalid_pointer_handler.
buffer_overflow_handler	set_buffer_overflow_handler (buffer_overflow_handler h)
	Exchanges the buffer_overflow_handler.
buffer_overflow_handler	get_buffer_overflow_handler ()
	Returns the buffer_overflow_handler.
temporary_stack &	get_temporary_stack (std::size_t initial_size=temporary_stack_initializer::default_stack_size)
template<typename T , typename U , class Impl >
bool	operator== (const std_allocator< T, Impl > &lhs, const std_allocator< U, Impl > &rhs) noexcept
template<typename T , typename U , class Impl >
bool	operator!= (const std_allocator< T, Impl > &lhs, const std_allocator< U, Impl > &rhs) noexcept
template<typename T , class RawAllocator >
auto	make_std_allocator (RawAllocator &&allocator) noexcept -> std_allocator< T, typename std::decay< RawAllocator >::type >
template<typename T , class RawAllocator >
any_std_allocator< T >	make_any_std_allocator (RawAllocator &&allocator) noexcept
template<class Tracker , class RawAllocator >
auto	make_tracked_allocator (Tracker t, RawAllocator &&alloc) -> tracked_allocator< Tracker, typename std::decay< RawAllocator >::type >
template<class RawAllocator , class Tracker , typename... Args>
auto	make_deeply_tracked_allocator (Tracker t, Args &&... args) -> deeply_tracked_allocator< Tracker, RawAllocator >
template<class RawAllocator >
auto	make_allocator_adapter (RawAllocator &&allocator) noexcept -> allocator_adapter< typename std::decay< RawAllocator >::type >
template<class Mutex , class RawAllocator >
auto	make_thread_safe_allocator (RawAllocator &&allocator) -> thread_safe_allocator< typename std::decay< RawAllocator >::type, Mutex >
template<class RawAllocator >
auto	make_allocator_reference (RawAllocator &&allocator) noexcept -> allocator_reference< typename std::decay< RawAllocator >::type >
template<class RawAllocator >
auto	make_aligned_allocator (std::size_t min_alignment, RawAllocator &&allocator) noexcept -> aligned_allocator< typename std::decay< RawAllocator >::type >
template<typename... Args>
auto	make_segregator (Args &&... args) -> segregator< typename std::decay< Args >::type... >
bool	operator!= (const memory_resource_allocator &lhs, const memory_resource_allocator &rhs) noexcept
template<typename T , class RawAllocator , class Container = deque<T, RawAllocator>>
std::stack< T, Container >	make_stack (RawAllocator &allocator)
template<typename T , class RawAllocator , class Container = deque<T, RawAllocator>>
std::queue< T, Container >	make_queue (RawAllocator &allocator)
template<typename T , class RawAllocator , class Container = deque<T, RawAllocator>, class Compare = std::less<T>>
std::priority_queue< T, Container, Compare >	make_priority_queue (RawAllocator &allocator, Compare comp={})
template<class BlockOrRawAllocator , typename... Args>
make_block_allocator_t< BlockOrRawAllocator >	make_block_allocator (std::size_t block_size, Args &&... args)
template<template< class... > class BlockAllocator, class BlockOrRawAllocator , typename... Args>
make_block_allocator_t< BlockOrRawAllocator, BlockAllocator >	make_block_allocator (std::size_t block_size, Args &&... args)
template<typename T , class RawAllocator >
bool	operator== (std::nullptr_t, const joint_ptr< T, RawAllocator > &ptr)
template<typename T , class RawAllocator >
bool	operator== (T *p, const joint_ptr< T, RawAllocator > &ptr)
template<typename T , class RawAllocator >
bool	operator!= (std::nullptr_t, const joint_ptr< T, RawAllocator > &ptr)
template<typename T , class RawAllocator >
bool	operator!= (T *p, const joint_ptr< T, RawAllocator > &ptr)
template<typename T , class RawAllocator , typename... Args>
auto	allocate_joint (RawAllocator &alloc, joint_size additional_size, Args &&... args) -> joint_ptr< T, RawAllocator >
template<typename T , class RawAllocator , typename... Args>
auto	allocate_joint (const RawAllocator &alloc, joint_size additional_size, Args &&... args) -> joint_ptr< T, RawAllocator >
template<class RawAllocator , typename T >
auto	clone_joint (RawAllocator &alloc, const joint_type< T > &joint) -> joint_ptr< T, RawAllocator >
template<class RawAllocator , typename T >
auto	clone_joint (const RawAllocator &alloc, const joint_type< T > &joint) -> joint_ptr< T, RawAllocator >
bool	operator!= (const joint_allocator &lhs, const joint_allocator &rhs) noexcept
template<std::size_t I, class Segregator , class Fallback >
auto	get_segregatable_allocator (const binary_segregator< Segregator, Fallback > &s) -> const segregatable_allocator_type< I, binary_segregator< Segregator, Fallback > >
template<class Segregator , class Fallback >
auto	get_fallback_allocator (const binary_segregator< Segregator, Fallback > &s) -> const fallback_allocator_type< binary_segregator< Segregator, Fallback > > &

Variables
const std::size_t	virtual_memory_page_size
	The page size of the virtual memory.
constexpr bool	cached_arena = true
constexpr bool	uncached_arena = false

Detailed Description

Memory namespace.

Function Documentation

get_fallback_allocator()

template<class Segregator , class Fallback >

auto wpi::memory::get_fallback_allocator

(

const binary_segregator< Segregator, Fallback > &

s

)

-> const fallback_allocator_type<binary_segregator<Segregator, Fallback>>&

get_segregatable_allocator()

template<std::size_t I, class Segregator , class Fallback >

auto wpi::memory::get_segregatable_allocator

(

const binary_segregator< Segregator, Fallback > &

s

)

-> const segregatable_allocator_type<I, binary_segregator<Segregator, Fallback>>

get_temporary_stack() [1/2]

temporary_stack & get_temporary_stack

(

std::size_t

initial_size = temporary_stack_initializer::default_stack_size

)

Effects:

Creates the per-thread temporary_stack with the given initial size, if it wasn't already created.

Returns:

The per-thread temporary_stack.

Requires:

There must be a per-thread temporary stack (WPI_MEMORY_TEMPORARY_STACK_MODE must not be equal to 0).

Note

If WPI_MEMORY_TEMPORARY_STACK_MODE is equal to 1, this function can create the temporary stack. But if there is no temporary_stack_initializer, it won't be destroyed.

operator!=() [1/5]

bool wpi::memory::operator!= ( const joint_allocator & lhs, const joint_allocator & rhs )

inlinenoexcept

operator!=() [2/5]

bool wpi::memory::operator!= ( const memory_resource_allocator & lhs, const memory_resource_allocator & rhs )

inlinenoexcept

operator!=() [3/5]

template<typename T , class RawAllocator >

bool wpi::memory::operator!=	(	std::nullptr_t	,
		const joint_ptr< T, RawAllocator > &	ptr )

operator!=() [4/5]

template<typename T , class RawAllocator >

bool wpi::memory::operator!=	(	T *	p,
		const joint_ptr< T, RawAllocator > &	ptr )

operator==() [1/3]

template<typename T , class RawAllocator >

bool wpi::memory::operator==	(	std::nullptr_t	,
		const joint_ptr< T, RawAllocator > &	ptr )

operator==() [2/3]

template<typename T , class RawAllocator >

bool wpi::memory::operator==	(	T *	p,
		const joint_ptr< T, RawAllocator > &	ptr )

threshold()

template<class RawAllocator >

threshold_segregatable< typename std::decay< RawAllocator >::type > wpi::memory::threshold	(	std::size_t	max_size,
		RawAllocator &&	alloc )

Returns:

A threshold_segregatable with the same parameter.