- `CLASSNAME = class (OBJ)`
- `OBJ = class (S, ID)`
- `OBJ = class (S, ID, PARENT, ...)`

Return the class name of `OBJ`, or create an object from the structure `S` with
class name `ID`.

Additional arguments name parent classes from which the new class is derived.

See also: `isa`, `typeinfo`.

### References

- https://www.mathworks.com/help/matlab/ref/class.html
- https://octave.sourceforge.io/octave/function/class.html