std::pointer_traits<Ptr>::to_address
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                    |   Defined in header  <memory>
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|   static element_type* to_address( pointer p ) noexcept;  | 
 (since C++20)  (optional member of program-defined specialization)  | 
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Constructs a raw pointer that references the same object as its pointer-like ("fancy pointer") argument.
This function, if defined, is the inverse of pointer_to, and exists as the customization point to be called by std::to_address.
Parameters
| p | - | fancy pointer/pointer-like object | 
Return value
A raw pointer of the type element_type* that references the same memory location as the argument p.
See also
|    [static]  | 
  obtains a dereferenceable pointer to its argument  (public static member function)  | 
|    (C++20)  | 
  obtains a raw pointer from a pointer-like type  (function template)  |