How do I cast a superclass object into a subclass object in MATLAB 7.7 (R2008b)?

If I have a superclass object, and I would like to cast it into a subclass object. In the pre-R2008b class system I could do this:

obj_sub = class(struct(obj_super),'mySubClass');

In Java, I can do this as:

 (mySubClass) obj_super

I do not see any straighforward way to do this in the current MATLAB class system.

Answer 1

[MathWorks Support Team]

MATLAB 7.7 (R2008b) does not have any functionality for directly casting a superclass object to a subclass object.

As a workaround (in any version of MATLAB), create and use a method which automatically copies over non-dependent property values:

function output = copyObject(input, output)
 C = metaclass(input);
 P = C.Properties;
 for k = 1:length(P)
   if ~P{k}.Dependent
     output.(P{k}.Name) = input.(P{k}.Name);
   end
 end
end

For more information about converting objects of one class to another and some examples, please refer to the following documentation page:

https://www.mathworks.com/help/matlab/matlab_oop/converting-objects-to-another-class.html