C++: Allocator

[]	Google. . , . , . ( . .)

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, , , , std::string, std::vector, , std::array, std::shared_ptr std::function, Allocator: , .

: std::allocator_traits , -, std::allocator_traits, .

A, T
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A, an Allocator for type T
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B, U
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B, the same Allocator for type U
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ptr, allocator_traits<A>::pointer, allocator_traits<A>::allocate()
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ptr, a value of type allocator_traits<A>::pointer, obtained by calling allocator_traits<A>::allocate()
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cptr, allocator_traits<A>::const_pointer, ptr
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cptr, a value of type allocator_traits<A>::const_pointer, obtained by conversion from ptr
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vptr, allocator_traits<A>::void_pointer, ptr
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vptr, a value of type allocator_traits<A>::void_pointer, obtained by conversion from ptr
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cvptr, allocator_traits<A>::const_void_pointer, cptr vptr
:
cvptr, a value of type allocator_traits<A>::const_void_pointer, obtained by conversion from cptr or from vptr
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xptr, dereferencable X
:
xptr, a dereferencable pointer to some type X
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Expression	Requirements	Return type
`A::pointer` ()	Satisfies `NullablePointer` and `RandomAccessIterator`
`A::const_pointer` ()	`A::pointer` is convertible to `A::const_pointer`. Satisfies `NullablePointer` and `RandomAccessIterator`
`A::void_pointer` ()	`A::pointer` is convertible to `A::void_pointer` `B::void_pointer` `A::void_pointer` . `NullablePointer` : `B::void_pointer` and `A::void_pointer` are the same type. Satisfies `NullablePointer` Google. . .
`A::const_void_pointer` ()	`A::pointer`, `A::const_pointer`, and `A::void_pointer` are convertible to `A::const_void_pointer` `B::const_void_pointer` `A::const_void_pointer` . `NullablePointer` : `B::const_void_pointer` and `A::const_void_pointer` are the same type. Satisfies `NullablePointer` Google. . .
`A::value_type`		the type `T`
`A::size_type` ()	`A::size_type` can represent the size of the largest object `A` can allocate	unsigned integer type
`A::difference_type` ()	`A::difference_type` can represent the difference of any two pointers to the objects allocated by `A`	signed integer type
`A::template rebind<U>::other` ( [1])	for any `U`, `B::template rebind<T>::other` is `A`	the type `B`
`*ptr`		`T&`
`*cptr`	`cptr` and `ptr` identify the same object	`const T&`
`ptr->m`	same as `(ptr).m`, if `(ptr).m` is well-defined	the type of `T::m`
`cptr->m`	same as `(cptr).m`, if `(cptr).m` is well-defined	the type of `T::m`
`static_cast<A::pointer>(vptr)`	`static_cast<A::pointer>(vptr) == ptr`	`A::pointer`
`static_cast<A::const_pointer>(cvptr)`	`static_cast<A::const_pointer>(vptr) == cptr`	`A::const_pointer`
`a.allocate(n)`	allocates storage suitable for `n` objects of type `T`, but does not construct them. May throw exceptions.	`A::pointer`
`a.allocate(n, cptr)` ()	same as `a.allocate(n)`, but may use `cptr` in unspecified manner to aid locality	`A::pointer`
`a.deallocate(ptr, n)`	deallocates storage previously allocated by a call to `a.allocate(n)`. Does not call destructors, if any objects were constructed, they must be destroyed before calling `a.deallocate()`. Does not throw exceptions.	(not used)
`a.max_size()` ()	the largest value that can be passed to `A::allocate()`	`A::size_type`
`a1 == a2`	returns `true` only if the storage allocated by the allocator `a1` can be deallocated through `a2`. Establishes reflexive, symmetric, and transitive relationship. Does not throw exceptions.	`bool`
`a1 != a2`	same as `!(a1==a2)`	`bool`
`A a1(a)`	Copy-constructs `a1` such that `a1 == a`. Does not throw exceptions.
`A a(b)`	Constructs `a` such that `B(a)==b` and `A(b)==a`. Does not throw exceptions.
`A a1(std::move(a))`	Constructs `a1` such that it equals the prior value of `a`. Does not throw exceptions.
`A a(std::move(b))`	Constructs `a` such that it equals the prior value of `A(b)`. Does not throw exceptions.
`a.construct(xptr, args)` ()	Constructs an object of type `X` in previously-allocated storage at the address pointed to by `xptr`, using args as the constructor arguments
`a.destroy(xptr)` ()	Destructs an object of type `X` pointed to by `xptr`, but does not deallocate any storage.
`a.select_on_container_copy_construction()` ()	Provides an instance of `A` to be used by the container that is copy-constructed from the one that uses `a` currently. Usually returns either a copy of `a` or a default-constructed `A()`.	`A`
`a.propagate_on_container_copy_assignment` ()	`true` if the allocator of type `A` needs to be copied when the container that uses it is copy-assigned	std::true_type or std::false_type or derived from such
`a.propagate_on_container_move_assignment` ()	`true` if the allocator of type `A` needs to be copied when the container that uses it is move-assigned	std::true_type or std::false_type or derived from such
`a.propagate_on_container_swap` ()	`true` if the allocators of type `A` need to be swapped when two containers that use them are swapped	std::true_type or std::false_type or derived from such

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[1] ( , STD :: allocator_traits), SomeAllocator <T, Args>, Args .







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C++: Allocator