Acts::AnyBase< SIZE > Class Template Reference

Small opaque type-erased type with configurable small buffer optimization. More...

#include <Acts/Utilities/Any.hpp>

Inheritance diagram for Acts::AnyBase< SIZE >:

Collaboration diagram for Acts::AnyBase< SIZE >:

Public Member Functions
	AnyBase ()=default
	AnyBase (AnyBase &&other) _ACTS_ANY_NOEXCEPT
	Move constructor.
	AnyBase (const AnyBase &other) _ACTS_ANY_NOEXCEPT
	Copy constructor.
template<typename T, typename... Args> requires (std::is_copy_assignable_v<std::decay_t<T>> && std::is_copy_constructible_v<std::decay_t<T>> && (sizeof(std::decay_t<T>) > SIZE || (std::is_move_assignable_v<std::decay_t<T>> && std::is_move_constructible_v<std::decay_t<T>>)))
	AnyBase (std::in_place_type_t< T >, Args &&... args)
	Construct with in-place type construction.
template<typename T> requires (!std::same_as<std::decay_t<T>, AnyBase<SIZE>> && std::is_copy_assignable_v<std::decay_t<T>> && std::is_copy_constructible_v<std::decay_t<T>> && (sizeof(std::decay_t<T>) > SIZE || (std::is_move_assignable_v<std::decay_t<T>> && std::is_move_constructible_v<std::decay_t<T>>)))
	AnyBase (T &&value) _ACTS_ANY_NOEXCEPT
	Construct from any value type.
	~AnyBase ()
template<typename T>
T &	as ()
	Get reference to stored value of specified type.
template<typename T>
const T &	as () const
	Get const reference to stored value of specified type.
template<typename T, typename... Args> requires (std::is_copy_assignable_v<std::decay_t<T>> && std::is_copy_constructible_v<std::decay_t<T>> && (sizeof(std::decay_t<T>) > SIZE || (std::is_move_assignable_v<std::decay_t<T>> && std::is_move_constructible_v<std::decay_t<T>>)))
T &	emplace (Args &&... args)
	Construct a new value in place, destroying any existing value.
	operator bool () const
	Check if the AnyBase contains a value.
AnyBase &	operator= (AnyBase &&other) _ACTS_ANY_NOEXCEPT
	Move assignment operator.
AnyBase &	operator= (const AnyBase &other) _ACTS_ANY_NOEXCEPT
	Copy assignment operator.

Detailed Description

template<std::size_t SIZE>
class Acts::AnyBase< SIZE >

Small opaque type-erased type with configurable small buffer optimization.

Note

Type requirements:

• All stored types must be copy constructible and copy assignable.
• Types stored locally (sizeof(T) <= SIZE) must also be move constructible and move assignable because local moves use move operations when not trivially movable (trivial moves fall back to buffer copies).
• Types stored on the heap (sizeof(T) > SIZE) are moved by stealing the pointer, so no move operations are required in that case.

In summary:

• Local storage: values live inside the internal buffer; moves may invoke move operations or buffer copies; copies use copy operations or buffer copies when trivial.
• Heap storage: values are allocated on the heap; moves transfer ownership of the pointer; copies allocate and copy-construct the pointee.

Constructor & Destructor Documentation

AnyBase() [1/5]

template<std::size_t SIZE>

template<typename T, typename... Args>
requires (std::is_copy_assignable_v<std::decay_t<T>> && std::is_copy_constructible_v<std::decay_t<T>> && (sizeof(std::decay_t<T>) > SIZE || (std::is_move_assignable_v<std::decay_t<T>> && std::is_move_constructible_v<std::decay_t<T>>)))

Acts::AnyBase< SIZE >::AnyBase ( std::in_place_type_t< T > , Args &&... args )

explicit

Construct with in-place type construction.

Template Parameters

T	Type to construct
Args	Constructor argument types

Parameters

args	Arguments to forward to T's constructor

AnyBase() [2/5]

template<std::size_t SIZE>

Acts::AnyBase< SIZE >::AnyBase ( )

default

AnyBase() [3/5]

template<std::size_t SIZE>

template<typename T>
requires (!std::same_as<std::decay_t<T>, AnyBase<SIZE>> && std::is_copy_assignable_v<std::decay_t<T>> && std::is_copy_constructible_v<std::decay_t<T>> && (sizeof(std::decay_t<T>) > SIZE || (std::is_move_assignable_v<std::decay_t<T>> && std::is_move_constructible_v<std::decay_t<T>>)))

Acts::AnyBase< SIZE >::AnyBase ( T && value )

explicit

Construct from any value type.

Template Parameters

T	Type of the value to store

Parameters

value

Value to store in the Any

~AnyBase()

template<std::size_t SIZE>

Acts::AnyBase< SIZE >::~AnyBase

(

)

AnyBase() [4/5]

template<std::size_t SIZE>

Acts::AnyBase< SIZE >::AnyBase

(

const AnyBase< SIZE > &

other

)

Copy constructor.

Parameters

other

The AnyBase to copy from

AnyBase() [5/5]

template<std::size_t SIZE>

Acts::AnyBase< SIZE >::AnyBase

(

AnyBase< SIZE > &&

other

)

Move constructor.

Parameters

other

The AnyBase to move from

Member Function Documentation

as() [1/2]

template<std::size_t SIZE>

template<typename T>

T & Acts::AnyBase< SIZE >::as

(

)

Get reference to stored value of specified type.

Template Parameters

T	Type to retrieve (must be exact type, no const/ref)

Returns

Reference to the stored value

Exceptions

std::bad_any_cast

if stored type doesn't match T

as() [2/2]

template<std::size_t SIZE>

template<typename T>

const T & Acts::AnyBase< SIZE >::as

(

)

const

Get const reference to stored value of specified type.

Template Parameters

T	Type to retrieve (must be exact type, no const/ref)

Returns

Const reference to the stored value

Exceptions

std::bad_any_cast

if stored type doesn't match T

emplace()

template<std::size_t SIZE>

template<typename T, typename... Args>
requires (std::is_copy_assignable_v<std::decay_t<T>> && std::is_copy_constructible_v<std::decay_t<T>> && (sizeof(std::decay_t<T>) > SIZE || (std::is_move_assignable_v<std::decay_t<T>> && std::is_move_constructible_v<std::decay_t<T>>)))

T & Acts::AnyBase< SIZE >::emplace

(

Args &&...

args

)

Construct a new value in place, destroying any existing value.

Template Parameters

T	Type to construct
Args	Constructor argument types

Parameters

args	Arguments to forward to T's constructor

Returns

Reference to the newly constructed value

operator bool()

template<std::size_t SIZE>

Acts::AnyBase< SIZE >::operator bool ( ) const

explicit

Check if the AnyBase contains a value.

Returns

True if a value is stored, false if empty

operator=() [1/2]

template<std::size_t SIZE>

AnyBase & Acts::AnyBase< SIZE >::operator=

(

AnyBase< SIZE > &&

other

)

Move assignment operator.

Parameters

other

The AnyBase to move from

Returns

Reference to this object

operator=() [2/2]

template<std::size_t SIZE>

AnyBase & Acts::AnyBase< SIZE >::operator=

(

const AnyBase< SIZE > &

other

)

Copy assignment operator.

Parameters

other

The AnyBase to copy from

Returns

Reference to this object