std::experimental::pmr::memory_resource::allocate
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                    < cpp | experimental | memory resource
                    
                                                            
                    |   void* allocate(std::size_t bytes, std::size_t alignment = alignof(std::max_align_t));  | 
(library fundamentals TS) | |
Allocates storage with a size of at least bytes bytes. The returned storage is aligned to the specified alignment if such alignment is supported, and to alignof(std::max_align_t) otherwise. 
Equivalent to return do_allocate(bytes, alignment);.
Exceptions
Throws an exception if storage of the requested size and alignment cannot be obtained.
See also
|    [virtual]  | 
   allocates memory  (virtual protected member function)  |