Partial Evaluation, Compilation

Once one has a working solver, it is obvious and attractive to run the constraints in a clause definition at read time or compile time and proceed with the answer constraints in place of the original constraints. This gets you constant folding and in fact the full algebraic power of the solver applied to the avoidance of computations at runtime. The mechanism to realize this idea is to use dump/3, call_residue/2 for the expansion of {}/1, via hook predicate user:goal_expansion/3).