REFINES

The REFINES keyword is used to declare models as specialisations of more general 'base' models.

MODEL vehicle;
   n_wheels IS_A integer_constant;
END vehicle;

MODEL bicycle REFINES vehicle;
   n_wheels :== 2;
END bicycle;

MODEL car REFINES vehicle;
   n_wheels :== 4;
END car;

See also Object-oriented modelling.