Type Alias


Prototype of a callback function used to get a description of a value or key in a dictionary.


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



The value to be described.

Return Value

A text description of value.


This callback is passed to CFDictionaryCreate(_:_:_:_:_:_:) in a CFDictionaryKeyCallBacks structure or CFDictionaryValueCallBacks. This callback is used by the CFCopyDescription(_:) function.

See Also


typealias CFDictionaryApplierFunction

Prototype of a callback function that may be applied to every key-value pair in a dictionary.

typealias CFDictionaryEqualCallBack

Prototype of a callback function used to determine if two values or keys in a dictionary are equal.

typealias CFDictionaryHashCallBack

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

typealias CFDictionaryReleaseCallBack

Prototype of a callback function used to release a key-value pair before it’s removed from a dictionary.

typealias CFDictionaryRetainCallBack

Prototype of a callback function used to retain a value or key being added to a dictionary.

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