MATLAB Object-Oriented Programming

Improve Version Compatibility with Default Values

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“Version Compatibility” on page 13-10

“Using a Default Property Value” on page 13-10

Version Compatibility

Default property values can help you implement version compatibility for saved objects.

For example, suppose that you add a property to version 2 of your class. Having a default

value enables MATLAB to assign a value to the new property when loading a version 1

object.

Similarly, suppose version 2 of your class removes a property. If a version 2 object is

saved and loaded into version 1, your loadobj method can use the default value from

version 1.

Using a Default Property Value

The EmployeeInfo class shows how to use property default values as a way to enhance

compatibility among versions. Version 1 of the EmployeeInfo class defines three

properties — Name, JobTitle, and Department.

classdef EmployeeInfo

properties

Name

JobTitle

Department

end

end

Version 2 of the EmployeeInfo class adds a property, Country, for the country name of

the employee location. The Country property has a default value of 'USA'.

classdef EmployeeInfo

properties

Name

JobTitle

Department

Country = 'USA'

13 Saving and Loading Objects