Dr. Dobb's Sourcebook January/February 1997
INTERFACE MyInterface;
EXCEPTION DivideByZero;
TYPE Calculator = OBJECT
METHODS
SetValue (v : REAL),
GetValue () : REAL,
Add (v : REAL),
Subtract (v : REAL),
Multiply (v : REAL),
Divide (v : REAL) RAISES DivideByZero END
END;