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( 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 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) |
© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
http://en.cppreference.com/w/cpp/memory/polymorphic_allocator/polymorphic_allocator