std::inout_ptr

 

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std::inout_ptr_t

Member functions

inout_ptr_t::inout_ptr_t

inout_ptr_t::~inout_ptr_t

inout_ptr_t::operator Pointer*inout_ptr_t::operator void**

Non-member functions

inout_ptr

 

Defined in header <memory>
template< class Pointer = void, class Smart, class... Args > auto inout_ptr( Smart& s, Args&&... args );		(since C++23) (constexpr since C++26)

Returns an inout_ptr_t with deduced template arguments that captures arguments for resetting by reference.

If construction of the return value (see below) is ill-formed, the program is ill-formed.

Parameters

s	-	the object (typically a smart pointer) to adapt
args	-	the arguments for resetting to capture

Return value

std::inout_ptr_t<Smart, P, Args&&>(s, std::forward<Args>(args)...), where P is

• Pointer, if Pointer is not same as void, otherwise,
• Smart::pointer, if it is valid and denotes a type, otherwise,
• Smart::element_type*, if Smart::element_type is valid and denotes a type, otherwise,
• std::pointer_traits<Smart>::element_type*.

Notes

Users may specify the template argument for the template parameter Pointer, in order to interoperate with foreign functions that take a Pointer*.

As all arguments for resetting are captured by reference, the returned inout_ptr_t should be a temporary object destroyed at the end of the full-expression containing the call to the foreign function, in order to avoid dangling references.

Feature-test macro	Value	Std	Feature
__cpp_lib_out_ptr	202106L	(C++23)	std::out_ptr, std::inout_ptr
	202311L	(C++26)	Freestanding std::out_ptr and std::inout_ptr
__cpp_lib_constexpr_memory	202506L	(C++26)	Constexpr std::inout_ptr

See also

out_ptr (C++23)	creates an out_ptr_t with an associated smart pointer and resetting arguments (function template)
make_uniquemake_unique_for_overwrite (C++14)(C++20)	creates a unique pointer that manages a new object (function template)
make_sharedmake_shared_for_overwrite (C++20)	creates a shared pointer that manages a new object (function template)