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std::pmr::polymorphic_allocator<T>::polymorphic_allocator

polymorphic_allocator() noexcept;
 (1) 
polymorphic_allocator( const polymorphic_allocator& other ) = default;
 (2) 
template< class U > 
polymorphic_allocator( const polymorphic_allocator<U>& other ) noexcept;
 (3) 
polymorphic_allocator( std::pmr::memory_resource* r );
 (4)

Constructs a new polymorphic_allocator.

1) Constructs a polymorphic_allocator using the return value of std::pmr::get_default_resource() as the underlying memory resource.
2,3) Constructs a polymorphic_allocator using other.resource() as the underlying memory resource.
4) Constructs a polymorphic_allocator using r as the underlying memory resource. This constructor provides an implicit conversion from std::pmr::memory_resource*.

Parameters

other - another polymorphic_allocator to copy from
r - pointer to the memory resource to use. May not be null

Exceptions

4) Throws nothing.

Notes

Copying a container using a polymorphic_allocator will not call the allocator's copy constructor. Instead, the new container will use the return value of select_on_container_copy_construction (a default-constructed polymorphic_allocator) as its allocator.

See also

create a new polymorphic_allocator for use by a container's copy constructor
(public member function)

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