std::pointer_traits::pointer_to

C++

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std::pointer_traits

Member functions

pointer_traits::pointer_to

Defined in header <memory>
static pointer pointer_to( element_type& r );	(1)	(since C++11) (member of pointer_traits<Ptr> specialization)
static pointer pointer_to( element_type& r ) noexcept;	(2)	(since C++11) (member of pointer_traits<T*> specialization)

Constructs a dereferenceable pointer or pointer-like object ("fancy 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)

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

Return value

A dereferenceable pointer to r, of the type pointer_traits<>::pointer.

Exceptions

1) Unspecified (typically same as Ptr::pointer_to)

Notes

The Boost.Intrusive library version of this function returns pointer(std::addressof(r)) if Ptr::pointer_to does not exist.

See also

addressof (C++11)	obtains actual address of an object, even if the & operator is overloaded (function template)
address (deprecated in C++17)(removed in C++20)	obtains the address of an object, even if operator& is overloaded (public member function of std::allocator)
to_address [static] (C++20)	obtains a raw pointer from a fancy pointer (inverse of pointer_to) (public static member function)
to_address (C++20)	obtains a raw pointer from a pointer-like type (function template)