any_std_allocator< T > Class Template Reference

Detailed Description

template<typename T>
class foonathan::memory::any_std_allocator< T >

An alias template for std_allocator using a type-erased RawAllocator.

This is the same as using a std_allocator with the tag type any_allocator. The implementation is optimized to call fewer virtual functions.

Typedefs
using	value_type = T
using	pointer = T *
using	const_pointer = const T *
using	reference = T &
using	const_reference = const T &
using	size_type = std::size_t
using	difference_type = std::ptrdiff_t
using	propagate_on_container_swap = typename prop_traits::propagate_on_container_swap
using	propagate_on_container_move_assignment = typename prop_traits::propagate_on_container_move_assignment
using	propagate_on_container_copy_assignment = typename prop_traits::propagate_on_container_copy_assignment
using	allocator_type = typename alloc_reference::allocator_type

Member Functions
std_allocator< T, any_allocator >	select_on_container_copy_construction () const
pointer	allocate (size_type n, void *=nullptr)
void	deallocate (pointer p, size_type n) noexcept
void	construct (U *p, Args &&... args)
void	destroy (U *p) noexcept
size_type	max_size () const noexcept
auto	get_allocator () noexcept -> decltype(std::declval< alloc_reference >().get_allocator())
auto	get_allocator () const noexcept -> decltype(std::declval< const alloc_reference >().get_allocator())

Related Functions
template<typename T , class RawAllocator >
any_std_allocator< T >	make_any_std_allocator (RawAllocator &&allocator) noexcept
bool	operator== (const std_allocator< T, Impl > &lhs, const std_allocator< U, Impl > &rhs) noexcept
bool	operator!= (const std_allocator< T, Impl > &lhs, const std_allocator< U, Impl > &rhs) noexcept
auto	make_std_allocator (any_allocator &&allocator) noexcept -> std_allocator< T, typename std::decay< any_allocator >::type >

Member Functions

select_on_container_copy_construction()

std_allocator< T, any_allocator > select_on_container_copy_construction ( ) const

inherited

Returns:

A copy of the allocator. This is required by the Allocator concept and forwards to the propagation_traits.

allocate()

pointer allocate ( size_type  n, void *  = nullptr  )

inherited

Effects:

Allocates memory using the underlying RawAllocator. If n is 1, it will call allocate_node(sizeof(T), alignof(T)), otherwise allocate_array(n, sizeof(T), alignof(T)).

Returns:

A pointer to a memory block suitable for n objects of type T.

Throws:

Anything thrown by the RawAllocator.

deallocate()

void deallocate ( pointer  p, size_type  n  )

noexceptinherited

Effects:

Deallcoates memory using the underlying RawAllocator. It will forward to the deallocation function in the same way as in allocate().

Requires:

The pointer must come from a previous call to allocate() with the same n on this object or any copy of it.

construct()

void construct ( U *  p, Args &&...  args  )

inherited

Effects:

Creates an object of type U at given address using the passed arguments.

destroy()

void destroy ( U *  p )

noexceptinherited

Effects:

Calls the destructor for an object of type U at given address.

max_size()

size_type max_size ( ) const

noexceptinherited

Returns:

The maximum size for an allocation which is max_array_size() / sizeof(value_type). This is only an upper bound, not the exact maximum.

get_allocator() [1/2]

auto get_allocator ( ) -> decltype(std::declval<alloc_reference>().get_allocator())

noexceptinherited

Effects:

Returns a reference to the referenced allocator.

Returns:

For stateful allocators: A (const) reference to the stored allocator. For stateless allocators: A temporary constructed allocator.

get_allocator() [2/2]

auto get_allocator ( ) const -> decltype(std::declval<const alloc_reference>().get_allocator())

noexceptinherited

Effects:

Returns a reference to the referenced allocator.

Returns:

For stateful allocators: A (const) reference to the stored allocator. For stateless allocators: A temporary constructed allocator.

Related Functions

make_any_std_allocator()

any_std_allocator< T > make_any_std_allocator ( RawAllocator &&  allocator )

related

Returns:

A new any_std_allocator for a given type using a certain allocator object.

operator==()

bool operator== ( const std_allocator< T, Impl > &  lhs, const std_allocator< U, Impl > &  rhs  )

related

Effects:

Compares two std_allocator object, they are equal if either stateless or reference the same allocator.

Returns:

The result of the comparision for equality.

operator!=()

bool operator!= ( const std_allocator< T, Impl > &  lhs, const std_allocator< U, Impl > &  rhs  )

related

Effects:

Compares two std_allocator object, they are equal if either stateless or reference the same allocator.

Returns:

The result of the comparision for inequality.

make_std_allocator()

auto make_std_allocator ( any_allocator &&  allocator ) -> std_allocator<T, typename std::decay<any_allocator >::type>

related

Returns:

A new std_allocator for a given type using a certain allocator object.