ANobject-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)