BloombergLP::bsltf::StdStatefulAllocator

Synopsis

Declared in <bsltf_stdstatefulallocator.h>

template<
    class TYPE,
    bool PROPAGATE_ON_CONTAINER_COPY_CONSTRUCTION = true,
    bool PROPAGATE_ON_CONTAINER_COPY_ASSIGNMENT = true,
    bool PROPAGATE_ON_CONTAINER_SWAP = true,
    bool PROPAGATE_ON_CONTAINER_MOVE_ASSIGNMENT = true,
    bool IS_ALWAYS_EQUAL = false>
class StdStatefulAllocator;

Description

This allocator implements the minimal interface to comply with section 17.6.3.5 ([allocator.requirements]) of the C++11 standard, while maintaining a distinct object state - in this case a wrapped pointer to a bslma::Allocator. The template is configurable to control its allocator propagation properties, but does not support the BDE "scoped" allocator model, as scoped allocators should never propagate. Instances of this allocator delegate their operations to the wrapped allocator that constitutes its state. Note that while we define the various traits used by the C++11 allocator traits facility, they actually mean very little for this component, as it is the consumer of the allocator's responsibility to check and apply the traits correctly, typically by using bsl::allocator_traits to perform all memory allocation tasks rather than using the allocator directly. The PROPAGATE_ON_CONTAINER_COPY_CONSTRUCTION flag is consumed directly though, in the static member function select_on_container_copy_construction.

Types

Name	Description
`rebind`	Nested trait providing an allocator for a different value type.

Type Aliases

Name	Description
`const_pointer`	Alias for a pointer to `const TYPE`.
`difference_type`	Alias for `std::ptrdiff_t`.
`is_always_equal`	Alias for an `allocator_traits` equality trait reflecting the `IS_ALWAYS_EQUAL` template parameter.
`pointer`	Alias for a pointer to `TYPE`.
`propagate_on_container_copy_assignment`	Alias for an `allocator_traits` propagation trait reflecting the `PROPAGATE_ON_CONTAINER_COPY_ASSIGNMENT` template parameter.
`propagate_on_container_move_assignment`	Alias for an `allocator_traits` propagation trait reflecting the `PROPAGATE_ON_CONTAINER_MOVE_ASSIGNMENT` template parameter.
`propagate_on_container_swap`	Alias for an `allocator_traits` propagation trait reflecting the `PROPAGATE_ON_CONTAINER_SWAP` template parameter.
`size_type`	Alias for `std::size_t`.
`value_type`	Alias for the allocated `TYPE`.

Member Functions

Name	Description
`StdStatefulAllocator` [constructor]	Constructors
`allocate`	Allocate space for the specified number of `TYPE` objects.
`allocator`	Return the address of the allocator wrapped by this object.
`construct`	Construct an `ELEMENT_TYPE` object at the specified address.
`deallocate`	Return previously allocated memory to this allocator.
`destroy`	Invoke the `ELEMENT_TYPE` destructor for the object at the specified `address`.
`max_size`	Return the maximum number of `TYPE` elements allocatable in one call.
`select_on_container_copy_construction`	Return the allocator to use when copy-constructing a container.
`operator BloombergLP::bslmf::NestedTraitDeclaration<StdStatefulAllocator, IsStdAllocator>`	Declare `StdStatefulAllocator` as a standard allocator.

Non-Member Functions

Name	Description
`operator!=`	Return whether two allocators wrap different underlying allocators.
`operator==`	Return whether two allocators wrap the same underlying allocator.