Granting Access to other classes

Hello everybody,

I am teaching myself how to use object oriented programming with MATLAB and have a question about access.

I have three current classes that need to interact with each other. One class, which I'll call main, is what the user will interface with (or the gui if I build one). Main stores all of the pertinent data that the use may want and has a few methods to perform some preprocessing and to construct the main object. Main also calls the constructors for the two other classes.

Another class, I'll call it instruction, loads information about the steps to process the data (this is a recursive process) and some other information.

The final class, which I'll call core, performs the core operations of the process.

Heres what my question is. Within main I have some "helper" methods that are used in the preprocessing. I want the access to these helper methods to be private so that the user cannot see or use them. Some of these helper functions also need to be used by the processes in core. My question is how do I grant access to the helper functions in main so that only main and core can access them? I have tried to understand the information provided here: http://www.mathworks.com/help/matlab/matlab_oop/selective-access-to-class-methods.html, but when I try something like:

classdef main < handle
%this is the main class
properties
    core  %the core object
    instruction  %the instruction object
end  %properties

methods (Access = {?core,?main})

... %some code

end  %methods

end  %class

Matlab gives me this error:

Illegal value for attribute 'Access'.
Parameter must be a string.

Any help would be greatly appreciated!

Andrew

Btw, I realize that having three different classes is unnecessary here but as I stated I am just learning object oriented programming and when I started this project I thought it would be a good idea to have multiple classes because the total project will be over 5000 lines of code.

Answer 1

[Andrew]

If anyone else has this question, the problem is I am running MATLAB R2011a and this feature wasn't implemented until R2012a.

But if you are having a similar issue you may want to consider what I am going to do and simply define a super class with the helper functions and then define core as a child of the super class.

Andrew