wunder%hpcerb@CE.HP.COM (Walter Underwood) (03/09/88)
Wm Leler's book discusses TK!Solver's algorithms and deficiencies, and uses the same contraint program as an example for his language, Bertrand. He also discusses the systems mentioned in other articles here: Sketchpad, ThingLab, IDEAL, Steele's work, and others that I can't remember right now. The main contribution of Wm's work is a firm theoretical foundation for constraint languages, plus the implementation work to make them run fast. He shows Turing equivalence, shows how to add constraints to enforce datatypes, etc. Bertrand is implemented in Scheme. Walter Underwood