Type Alias


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


typealias CFDictionaryRetainCallBack = (CFAllocator?, UnsafeRawPointer?) -> UnsafeRawPointer?



The dictionary’s allocator.


The value being added to the dictionary.

Return Value

The value or key to store in the dictionary, which is usually the value parameter passed to this callback, but may be a different value if a different value should be stored in the collection.


See Also


typealias CFDictionaryApplierFunction

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

typealias CFDictionaryCopyDescriptionCallBack

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

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