RosettaCodeData/Task/Inheritance-Single/Simula/inheritance-single.simula

begin

    class Animal;
        ! instance variables;
    begin
        ! methods;
    end;

    Animal class Dog;
    begin
    end;

    Animal class Cat;
    begin
    end;

    Dog class Lab;
    begin
    end;

    Dog class Collie;
    begin
    end;

end