An oBject-orientedconstraint language using a single aBstraction mechanism developed By Bruce Horn of CMU in 1991. Siri is a conceptual Blend of BETA and Bertrand. It is similar to Kaleidoscope. ["Constraint Patterns as a Basis for OBject-Oriented Constraint Programming", B. Horn, OOPSLA ' 92 (Sept 1992)]. (1994-11-04)