std::scoped_allocator_adaptor

 

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std::scoped_allocator_adaptor

Member functions

scoped_allocator_adaptor::scoped_allocator_adaptor

scoped_allocator_adaptor::~scoped_allocator_adaptor

scoped_allocator_adaptor::operator=

scoped_allocator_adaptor::inner_allocator

scoped_allocator_adaptor::outer_allocator

scoped_allocator_adaptor::allocate

scoped_allocator_adaptor::deallocate

scoped_allocator_adaptor::max_size

scoped_allocator_adaptor::construct

scoped_allocator_adaptor::destroy

scoped_allocator_adaptor::select_on_container_copy_construction

scoped_allocator_adaptor::outermost scoped_allocator_adaptor::outermost-construct scoped_allocator_adaptor::outermost-destroy

Non-member functions

operator==operator!= (until C++20)

Deduction guides(C++17)

 

Template:ddcl list begin <tr class="t-dsc-header">

<td>

Defined in header <scoped_allocator>

</td>

<td></td> <td></td> </tr> <tr class="t-dcl ">

<td >

template< class OuterAlloc, class... InnerAlloc >
class scoped_allocator_adaptor : public OuterAlloc;

</td>

<td class="t-dcl-nopad"> </td> <td > (since C++11) </td> </tr> Template:ddcl list end

The std::scoped_allocator_adaptor class template is an allocator which can be used with multilevel containers (vector of sets of lists of tuples of maps, etc). It is instantiated with one outer allocator type OuterAlloc and zero or more inner allocator types InnerAlloc.... A container constructed directly with a scoped_allocator_adaptor uses OuterAlloc to allocate its elements, but if an element is itself a container, it uses the first inner allocator. The elements of that container, if they are themselves containers, use the second inner allocator, etc. If there are more levels to the container than there are inner allocators, the last inner allocator is reused for all further nested containers.

For the purpose of scoped_allocator_adaptor, if the next inner allocator is A, any class T for which std::uses_allocator<T,A>::value == true participates in the recursion as if it was a container. Additionally, std::pair is treated as such a container by specific overloads of scoped_allocator_adaptor::construct.

Typical implementation holds an instance of a std::scoped_allocator_adaptor<InnerAllocs...> as a member object.

Member types

Type	Definition
outer_allocator_type	OuterAlloc
inner_allocator_type	scoped_allocator_adaptor<InnerAllocs...> or, if sizeof...(InnerAllocs) == 0, scoped_allocator_adaptor<OuterAlloc>
value_type	std::allocator_traits<OuterAlloc>::value_type
size_type	std::allocator_traits<OuterAlloc>::size_type
difference_type	std::allocator_traits<OuterAlloc>::difference_type
pointer	std::allocator_traits<OuterAlloc>::pointer
const_pointer	std::allocator_traits<OuterAlloc>::const_pointer
void_pointer	std::allocator_traits<OuterAlloc>::void_pointer
const_void_pointer	std::allocator_traits<OuterAlloc>::const_void_pointer
propagate_on_container_copy_assignment std::true_type if std::allocator_traits<A>::propagate_on_container_copy_assignment::value is true for at least one allocator A among OuterAlloc and InnerAlloc...
propagate_on_container_move_assignment std::true_type if std::allocator_traits<A>::propagate_on_container_move_assignment::value is true for at least one allocator A among OuterAlloc and InnerAlloc...
propagate_on_container_swap std::true_type if std::allocator_traits<A>::propagate_on_container_swap::value is true for at least one allocator A among OuterAlloc and InnerAlloc...
rebind template< class T > struct rebind { typedef scoped_allocator_adaptor< std::allocator_traits<OuterAlloc>::template rebind_alloc<T>, InnerAllocs... > other; };

Member functions

Template:cpp/memory/scoped allocator adaptor/dcl list scoped allocator adaptorTemplate:cpp/memory/scoped allocator adaptor/dcl list ~scoped allocator adaptorTemplate:cpp/memory/scoped allocator adaptor/dcl list inner allocatorTemplate:cpp/memory/scoped allocator adaptor/dcl list outer allocatorTemplate:cpp/memory/scoped allocator adaptor/dcl list allocateTemplate:cpp/memory/scoped allocator adaptor/dcl list deallocateTemplate:cpp/memory/scoped allocator adaptor/dcl list max sizeTemplate:cpp/memory/scoped allocator adaptor/dcl list constructTemplate:cpp/memory/scoped allocator adaptor/dcl list destroyTemplate:cpp/memory/scoped allocator adaptor/dcl list select on container copy construction

Non-member functions

Template:cpp/memory/scoped allocator adaptor/dcl list operator cmp

See also

Template:cpp/memory/dcl list allocator traitsTemplate:cpp/memory/dcl list uses allocatorTemplate:cpp/memory/dcl list allocator