How can I typecast a variable to a custom Typedef in generated code?

I have created a custom Type "MyTypeDef".

I have a Simulink model with a MATLAB function block which contains the following line:

coder.ceval('TestFunc',cast(u,'like',dt));

Where u is an input variable named "TestDefine" and dt is of type "MyTypeDef".

I am trying to cast TestDefine of type double to MyTypeDef.

The generated code is

TestFunc(TestDefine);

However I am expecting to see:

TestFunc((MyTypeDef)TestDefine);

Is the above code expected behavior? Is there an option to set to generate the code in the way I am expecting?

Answer 1

[MathWorks Support Team]

The behavior you are experiencing is expected. The coder identifies that the underlying base types for u and dt are the same and thus no typecast is necessary. You can "force" the typecast by changing either u (TestDefine) or dt to another base type, for example single; this would result in a typecast being shown:

Another option is for the customer to treat his "MyTypeDef" type as an opaque type and declare it as so. Then the MATLAB code would look like:

Which would result in the desired code:

However, note that the type is no longer determined by dt. You would probably have to use this in combination with a switch-case statement to insert the appropriate type based on dt.