MATLAB Object-Oriented Programming

Mutable Handle vs. Immutable Value Enumeration

Members

In this section...

“Select Handle- or Value-Based Enumerations” on page 14-34

“Value-Based Enumeration Classes” on page 14-34

“Handle-Based Enumeration Classes” on page 14-36

“Represent State with Enumerations” on page 14-39

Select Handle- or Value-Based Enumerations

Use a handle enumeration to enumerate a set of objects whose state can change over

time. Use a value enumeration to enumerate a set of abstract (and immutable) values. For

information about handle and value classes, see “Comparison of Handle and Value

Classes” on page 7-2.

Value-Based Enumeration Classes

A value-based enumeration class has a fixed set of specific values. Modify these values by

changing the values of properties. Doing so expands or changes the fixed set of values for

this enumeration class.

Inherited Property SetAccess Must Be Immutable

Value-based enumeration classes implicitly define the SetAccess attributes of all

properties as immutable. You cannot set the SetAccess attribute to any other value.

However, all superclass properties must explicitly define property SetAccess as

immutable.

Enumeration Members Remain Constant

An instance of a value-based enumeration class is unique until the class is cleared and

reloaded. For example, given this class:

classdef WeekDays

enumeration

Monday, Tuesday, Wednesday, Thursday, Friday

14 Enumerations