DEFINITION MODULE People;
  TYPE Gender = (unknown,male,female);
  CLASS Person;
    name    :ARRAY [0..40] OF CHAR;
    sex     :Gender;
    PROCEDURE isMale() :BOOLEAN;
  END Person;

  TYPE  LanguageName = ARRAY [0..10] OF CHAR;
  CLASS Programmer;
    INHERIT Person;
    favoriteLanguage :LanguageName;
    PROCEDURE isSmart() :BOOLEAN;
  END Programmer;
END People.
