std::inout_ptr

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Memory management library

voidify

(exposition only*)

Allocators

allocator
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Uninitialized memory algorithms

uninitialized_copy
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construct_at (C++20)

uninitialized_default_construct (C++17)
uninitialized_value_construct (C++17)
destroy (C++17)
uninitialized_default_construct_n (C++17)
uninitialized_value_construct_n (C++17)
destroy_n (C++17)
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Constrained uninitialized memory algorithms

ranges::uninitialized_copy (C++20)
ranges::uninitialized_fill (C++20)
ranges::uninitialized_move (C++20)
ranges::uninitialized_copy_n (C++20)
ranges::uninitialized_fill_n (C++20)
ranges::uninitialized_move_n (C++20)
ranges::construct_at (C++20)

ranges::uninitialized_default_construct (C++20)
ranges::uninitialized_value_construct (C++20)
ranges::destroy (C++20)
ranges::uninitialized_default_construct_n (C++20)
ranges::uninitialized_value_construct_n (C++20)
ranges::destroy_n (C++20)
ranges::destroy_at (C++20)

Memory resources

pmr::memory_resource (C++17)
pmr::get_default_resource (C++17)
pmr::set_default_resource (C++17)
pmr::new_delete_resource (C++17)
pmr::pool_options (C++17)

pmr::null_memory_resource (C++17)
pmr::synchronized_pool_resource (C++17)
pmr::unsynchronized_pool_resource (C++17)
pmr::monotonic_buffer_resource (C++17)

Explicit lifetime management
start_lifetime_as (C++23)
start_lifetime_as_array (C++23)

Types for composite class design
indirect (C++26)
polymorphic (C++26)

Uninitialized storage(until C++20)

raw_storage_iterator (until C++20*)
get_temporary_buffer (until C++20*)

return_temporary_buffer (until C++20*)

Garbage collector support(until C++23)

declare_reachable (C++11)(until C++23)
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pointer_safety (C++11)(until C++23)

undeclare_reachable (C++11)(until C++23)
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get_pointer_safety (C++11)(until C++23)

Low level memory
management

operator newoperator new[]

operator deleteoperator delete[]

(C++11)

(C++11)

(C++17)

(C++20)

(C++17)

(C++11)

(C++11)

(C++11)

(until C++17*)

(C++11)

(C++17)

(C++26)

(C++26)

enable_shared_from_this

(C++11)

(C++11)

(C++11)

(C++23)

(C++23)

(C++11)

(C++20)

(C++11)

(C++11)

(C++20)

is_sufficiently_aligned

(C++26)

C Library

malloc
calloc
realloc

free
aligned_alloc (C++17)

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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 Pointerinout_ptr_t::operator void*
Non-member functions
inout_ptr

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

Returns aninout_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.

[edit]Parameters

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

[edit]Return value

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

Pointer, ifPointer is not avoid type, otherwise,
Smart::pointer, if it is valid and denotes a type, otherwise,
Smart::element_type*, ifSmart::element_type is valid and denotes a type, otherwise,
std::pointer_traits<Smart>::element_type*.

[edit]Notes

Users may specify the template argument for the template parameterPointer, in order to interoperate with foreign functions that take aPointer*.

As all arguments for resetting are captured by reference, the returnedinout_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
`__cpp_lib_out_ptr`	`202311L`	(C++26)	freestanding`std::out_ptr` andstd::inout_ptr

[edit]Example

This section is incomplete
Reason: no example

[edit]See also

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