Function

class_setVersion(_:_:)

Sets the version number of a class definition.

Declaration

func class_setVersion(_ cls: AnyClass!, _ version: Int32)

Parameters

theClass

A pointer to an Class data structure. Pass the class definition for which you wish to set the version.

version

An integer. Pass the new version number of the class definition.

Discussion

You can use the version number of the class definition to provide versioning of the interface that your class represents to other classes. This is especially useful for object serialization (that is, archiving of the object in a flattened form), where it is important to recognize changes to the layout of the instance variables in different class-definition versions.

Classes derived from the Foundation framework NSObject class can set the class-definition version number using the setVersion: class method, which is implemented using the class_setVersion function.