std::out_ptr

 

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std::out_ptr_t

Member functions

out_ptr_t::out_ptr_t (C++23)

out_ptr_t::~out_ptr_t (C++23)

out_ptr_t::operator Pointer*out_ptr_t::operator void** (C++23)(C++23)

Non-member functions

out_ptr (C++23)

 

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

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

The program is ill-formed if construction of the return value (see below) is ill-formed.

Parameters

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

Return value

std::out_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 out_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:

__cpp_lib_out_ptr

See also

inout_ptr (C++23)	creates an inout_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)