std::pmr::polymorphic_allocator<T>::allocate_bytes
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                    < cpp | memory | polymorphic allocator
                    
                                                            
                    |   void* allocate_bytes( std::size_t nbytes, std::size_t alignment = alignof(std::max_align_t) );  | 
(since C++20) | |
Allocates nbytes bytes of storage at specified alignment alignment using the underlying memory resource. Equivalent to return resource()->allocate(nbytes, alignment);.
Parameters
| nbytes | - | the number of bytes to allocate | 
| alignment | - | the alignment to use | 
Return value
A pointer to the allocated storage.
Notes
This function was introduced for use with the fully-specialized allocator std::pmr::polymorphic_allocator<>, but it may be useful in any specialization.
The return type is void* (rather than, e.g., std::byte*) to support conversion to an arbitrary pointer type U* by static_cast<U*>.
Exceptions
May throw any exceptions thrown by the call to resource()->allocate.
See also
|    (C++20)  | 
  allocates raw memory suitable for an object or an array  (public member function)  | 
|    (C++20)  | 
  allocates and constructs an object  (public member function)  | 
|   allocate memory  (public member function)  | |
|    [static]  | 
  allocates uninitialized storage using the allocator  (public static member function of std::allocator_traits<Alloc>)  | 
|   allocates memory  (public member function of std::pmr::memory_resource)  |