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.

See Also

Working with Classes

func class_getName(AnyClass?)

Returns the name of a class.

func class_getSuperclass(AnyClass?)

Returns the superclass of a class.

func class_isMetaClass(AnyClass?)

Returns a Boolean value that indicates whether a class object is a metaclass.

func class_getInstanceSize(AnyClass?)

Returns the size of instances of a class.

func class_getInstanceVariable(AnyClass?, UnsafePointer<Int8>)

Returns the Ivar for a specified instance variable of a given class.

func class_getClassVariable(AnyClass?, UnsafePointer<Int8>)

Returns the Ivar for a specified class variable of a given class.

func class_copyIvarList(AnyClass?, UnsafeMutablePointer<UInt32>?)

Describes the instance variables declared by a class.

func class_getIvarLayout(AnyClass?)

Returns a description of the Ivar layout for a given class.

func class_setIvarLayout(AnyClass?, UnsafePointer<UInt8>?)

Sets the Ivar layout for a given class.

func class_getWeakIvarLayout(AnyClass?)

Returns a description of the layout of weak Ivars for a given class.

func class_setWeakIvarLayout(AnyClass?, UnsafePointer<UInt8>?)

Sets the layout for weak Ivars for a given class.

func class_getProperty(AnyClass?, UnsafePointer<Int8>)

Returns a property with a given name of a given class.

func class_addMethod(AnyClass?, Selector, IMP, UnsafePointer<Int8>?)

Adds a new method to a class with a given name and implementation.

func class_getInstanceMethod(AnyClass?, Selector)

Returns a specified instance method for a given class.

func class_getClassMethod(AnyClass?, Selector)

Returns a pointer to the data structure describing a given class method for a given class.

func class_copyMethodList(AnyClass?, UnsafeMutablePointer<UInt32>?)

Describes the instance methods implemented by a class.

func class_replaceMethod(AnyClass?, Selector, IMP, UnsafePointer<Int8>?)

Replaces the implementation of a method for a given class.

func class_getMethodImplementation(AnyClass?, Selector)

Returns the function pointer that would be called if a particular message were sent to an instance of a class.

func class_getMethodImplementation_stret(AnyClass?, Selector)

Returns the function pointer that would be called if a particular message were sent to an instance of a class.

func class_respondsToSelector(AnyClass?, Selector)

Returns a Boolean value that indicates whether instances of a class respond to a particular selector.

func class_conformsToProtocol(AnyClass?, Protocol?)

Returns a Boolean value that indicates whether a class conforms to a given protocol.

func class_getVersion(AnyClass?)

Returns the version number of a class definition.