Recursive data structure error in mex compiling of object-oriented program

I am attempting to use Matlab Coder to build a mex function. The function itself is the front end for an object oriented program. I'm getting a compiling error and can reproduce it with a simple toy example.

The following example compiles and executes without errors. It consists of three files: the main function, an example parent class, and an example child class:

    function str = main
        M = ParentClass;
        str = 'Done';
    end

...

 classdef ParentClass < handle

    properties
        Child;
    end

    methods
        function self = ParentClass
            self.Child = ChildClass;
        end
    end
 end

...

 classdef ChildClass < handle

    properties
    end

    methods
        function self = ChildClass

        end
    end    
 end

I'd like the child to keep a reference to its parent as a property, which is key for many design patterns. However, this causes a compiling error. I implement it by modifying the two classdefs as shown below. When the parent creates the child, the child stores the parent during the constructor.

 classdef ParentClass < handle

    properties
        Child;
    end

    methods
        function self = ParentClass
            self.Child = ChildClass(self);  % Line with the compiling error
        end
    end
 end

...

 classdef ChildClass < handle

    properties
        Parent
    end

    methods
        function self = ChildClass(Parent)
            self.Parent = Parent;
        end
    end    
 end

This produces the coder compiling error "This expression and its property 'Parent.Child' have the same class. Code generation does not support recursive data structures."

Is there a simple way around this language limitation? It works fine in the regular matlab environment, and this behavior is supported in other languages.

edit: Essentially, I'm looking for a way for the Child and Parent to have a reference to each other that is compatible with Matlab Coder.

Thanks in advance for the help

[Dominik Müller]

Hi,

I know the question is already sth like 4 years old but is there an answer on this topic? I'm stuck to the same problem right now.

Answer 1

[Darshan Ramakant Bhat]

Unfortunately MATLAB Coder does not support recursive data structures yet. It is documented in the below page :

https://www.mathworks.com/help/simulink/ug/how-working-with-matlab-classes-is-different-for-code-generation.html#bta5j96

We have made an internal request to support this in one of the future releases.