std::pointer_traits

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Defined in header <memory>
template< class Ptr > struct pointer_traits;	(1)	(since C++11)
template< class T > struct pointer_traits<T*>;	(2)	(since C++11)

The pointer_traits class template provides the standardized way to access certain properties of pointer-like types.

1) The non-specialized pointer_traits declares the following types:

Contents 1 Member types 2 Member alias templates 3 Member functions 4 Member types 5 Member alias templates 6 Member functions 7 See also

[edit] Member types

Type	Definition
pointer	Ptr
element_type	Ptr::element_type if present. Otherwise T if Ptr is a template instantiation Template<T, Args...>
difference_type	Ptr::difference_type if present, otherwise std::ptrdiff_t

[edit] Member alias templates

Template	Definition
template <class U> using rebind	Ptr::rebind<U> if exists, otherwise Tempate<U, Args...> if Ptr is a template instantiation Template<T, Args...>

[edit] Member functions

pointer_to [static]	obtains a dereferencable pointer to its argument (public static member function)

2) A specialization is provided for pointer types, T*, which declares the following types

[edit] Member types

Type	Definition
pointer	T*
element_type	T
difference_type	std::ptrdiff_t

[edit] Member alias templates

Template	Definition
template< class U > using rebind	U*

[edit] Member functions

pointer_to [static]	obtains a dereferencable pointer to its argument} (public static member function)

[edit] See also

allocator_traits (C++11)	provides information about allocator types (class template)
addressof (C++11)	obtains actual address of an object, even if the & operator is overloaded (function template)