Gus Lopez, Bjorn Freeman-Benson, and Alan Borning

The Constraint Imperative Programming (CIP) family of languages integrates constraints and imperative, object-oriented programming. In addition to com- bining the useful features of both paradigms, there are synergistic efiects of this integration, such as the ability to deflne constraints over user-deflned domains. We discuss characteristics of the CIP family and provide a rationale for its creation. The synergy of constraints and objects imposes additional challenges for the provision of constructs, such as object identity and class membership, that are well-understood in conventional language paradigms. We discuss the beneflts and challenges of combining the constraint and imperative paradigms, and present our current ideas in the context of the design and implementation of the Kaleidoscope'93 language.