std::pointer_traits::pointer_to
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                    < cpp | memory | pointer traits
                    
                                                            
                    |   Defined in header  
<memory>
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|   static pointer pointer_traits<Ptr>::pointer_to(element_type& r ); 
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(since C++11) | |
|   static pointer pointer_traits<T*>::pointer_to(element_type& r); 
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(since C++11) | |
Constructs a dereferenceable pointer to its argument.
1) The version of this function in the non-specialized std::pointer_traits template simply calls Ptr::pointer_to(r), and if Ptr does not provide a static member function 
pointer_to, instantiation of this function is a compile-time error.
2) The version of this function in the specialization of std::pointer_traits for pointer types returns std::addressof(r)
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[edit] Parameters
| r | - |   reference to an object of type element_type&, except if element_type is void, in which case the type of r is unspecified
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[edit] Return value
A dereferenceable pointer to r, of the type pointer_traits<>::pointer.
[edit] Exceptions
1) Unspecified (typically same as Ptr::pointer_to)
2)[edit] Notes
The boost library version of this function returns pointer(std::addressof(r)) if Ptr::pointer_to does not exist.
[edit] See also
|    (C++11) 
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   obtains actual address of an object, even if the & operator is overloaded   (function template)  | 
|    obtains the address of an object, even if operator& is overloaded  (public member function of std::allocator) 
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