Objective-C Runtime

Gain low-level access to the Objective-C runtime and the Objective-C root types.


The Objective-C Runtime module APIs define the base of the Objective-C language. These APIs include:

  • Types such as the NSObject class and the NSObjectProtocol protocol that provide the root functionality of most Objective-C classes

  • Functions and data structures that comprise the Objective-C runtime, which provides support for the dynamic properties of the Objective-C language

You typically don't need to use this module directly.



class NSObject

The root class of most Objective-C class hierarchies, from which subclasses inherit a basic interface to the runtime system and the ability to behave as Objective-C objects.


protocol NSObjectProtocol

The group of methods that are fundamental to all Objective-C objects.


enum objc_AssociationPolicy

Type to specify the behavior of an association.

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