std::to_address

 

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Defined in header <memory>
template< class Ptr > auto to_address(const Ptr& p) noexcept;	(1)	(since C++20)
template< class T > constexpr T* to_address(T* p) noexcept;	(2)	(since C++20)

Obtain the address represented by p without forming a reference to the pointee.

1) Fancy pointer overload: If the expression std::pointer_traits<Ptr>::to_address(p) is well-formed, returns the result of that expression. Otherwise, returns std::to_address(p.operator->()).

2) Raw pointer overload: If T is a function type, the program is ill-formed. Otherwise, returns p unmodified.

Parameters

p

-

fancy or raw pointer

Return value

Raw pointer that represents the same address as p does.

Notes

std::to_address can be used even when p does not reference storage that has an object constructed in it, in which case std::addressof(*p) cannot be used because there's no valid object for the parameter of std::addressof to bind to.

See also

pointer_traits (C++11)	provides information about pointer-like types (class template)
to_address [static] (C++20)(optional)	obtains a raw pointer from a fancy pointer (inverse of pointer_to) (public static member function of std::pointer_traits<Ptr>)