Unmanaged

struct Unmanaged<Instance where Instance : AnyObject>

A type for propagating an unmanaged object reference.

When you use this type, you become partially responsible for keeping the object alive.

Import import Swift

Static Methods

static func fromOpaque(_:)

Unsafely turns an opaque C pointer into an unmanaged class reference.

This operation does not change reference counts.

let str: CFString = Unmanaged.fromOpaque(ptr).takeUnretainedValue()

value: An opaque C pointer. Returns: An unmanaged class reference to value.

Declaration

static func fromOpaque(_ value: UnsafeRawPointer) -> Unmanaged<Instance>
static func passRetained(_:)

Creates an unmanaged reference with an unbalanced retain.

The instance passed as value will leak if nothing eventually balances the retain.

This is useful when passing an object to an API which Swift does not know the ownership rules for, but you know that the API expects you to pass the object at +1.

value: A class instance. Returns: An unmanaged reference to the object passed as value.

Declaration

static func passRetained(_ value: Instance) -> Unmanaged<Instance>
static func passUnretained(_:)

Creates an unmanaged reference without performing an unbalanced retain.

This is useful when passing a reference to an API which Swift does not know the ownership rules for, but you know that the API expects you to pass the object at +0.

CFArraySetValueAtIndex(.passUnretained(array), i,
                       .passUnretained(object))

value: A class instance. Returns: An unmanaged reference to the object passed as value.

Declaration

static func passUnretained(_ value: Instance) -> Unmanaged<Instance>

Instance Methods

func autorelease()

Performs an unbalanced autorelease of the object.

Declaration

func autorelease() -> Unmanaged<Instance>
func release()

Performs an unbalanced release of the object.

Declaration

func release()
func retain()

Performs an unbalanced retain of the object.

Declaration

func retain() -> Unmanaged<Instance>
func takeRetainedValue()

Gets the value of this unmanaged reference as a managed reference and consumes an unbalanced retain of it.

This is useful when a function returns an unmanaged reference and you know that you're responsible for releasing the result.

Returns: The object referenced by this Unmanaged instance.

Declaration

func takeRetainedValue() -> Instance
func takeUnretainedValue()

Gets the value of this unmanaged reference as a managed reference without consuming an unbalanced retain of it.

This is useful when a function returns an unmanaged reference and you know that you're not responsible for releasing the result.

Returns: The object referenced by this Unmanaged instance.

Declaration

func takeUnretainedValue() -> Instance
func toOpaque()

Unsafely converts an unmanaged class reference to a pointer.

This operation does not change reference counts.

let str0: CFString = "boxcar"
let bits = Unmanaged.passUnretained(str0)
let ptr = bits.toOpaque()

Returns: An opaque pointer to the value of this unmanaged reference.

Declaration

func toOpaque() -> UnsafeMutableRawPointer