Type Alias

CFBagCopyDescriptionCallBack

Prototype of a callback function used to get a description of a value in a bag.

Declaration

typealias CFBagCopyDescriptionCallBack = (UnsafeRawPointer?) -> Unmanaged<CFString>?

Parameters

value

The value to be described.

Return Value

A textual description of value. Ownership follows the The Create Rule.

Discussion

This callback is passed to CFBagCreate(_:_:_:_:) in a CFBagCallBacks structure. This callback is used by the CFCopyDescription(_:) function.

See Also

Callbacks

typealias CFBagApplierFunction

Prototype of a callback function that may be applied to every value in a bag.

typealias CFBagEqualCallBack

Prototype of a callback function used to determine if two values in a bag are equal.

typealias CFBagHashCallBack

Prototype of a callback function invoked to compute a hash code for a value. Hash codes are used when values are accessed, added, or removed from a collection.

typealias CFBagReleaseCallBack

Prototype of a callback function used to release a value before it’s removed from a bag.

typealias CFBagRetainCallBack

Prototype of a callback function used to retain a value being added to a bag.

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