MATLAB: How to pass a class name as argument to a function

Question

Hello,

I'd like to initialize an element of a class with another class instance, and I'd like to pass in the particular class as an object. For example:

classdef Aclass < handle
  properties
    thingObj
  end
    methods
       function this = Aclass(thingClassName)
         this.thingObj = thingClassName(arg1,arg2,etc);
       end
    end
  end

This code doesn't work, though ("Index exceeds matrix dimensions"). I assume the problem is you can't call the () operator on an existing object.

Instead, I do this, which does work, but isn't pretty:

 classdef SomeClass < handle
    properties
      thingObj
    end
    methods
       function this = SomeClass(thingClassName)
         this.thingObj = eval([class(thingClassName) '(arg1,arg2,etc)']);
       end
    end
  end

There's no checking in the string argument list, and errors in this line are hard to debug.

I could instantiate the object outside the constructor, but that's problematic. I'd like to instantiate the object within the "SomeClass" constructor because it knows the right way to do it.

I'm guessing this is really simple and that I haven't stumbled on the right way yet. Any ideas?

Thanks,

Charles

Answer 1

I think the first classdef ("Aclass") works fine, as long as you pass to its constructor the handle of the class you want instantiated. So, for example,

myobj = Aclass(@theClassToInstantiate)