Backjumping is Exception Handling

TL;DR

This paper shows how Prolog's catch and throw can be used to implement backjumping, enhancing control flow in logic programming with practical applications like graph coloring and SAT solving.

Contribution

It demonstrates that catch and throw can effectively implement backjumping semantics, providing a new perspective on exception handling in logic programming.

Findings

Implemented backjumping in Prolog using catch and throw

Applied backjumping to graph coloring and SAT solving

Showed improved search efficiency with backjumping

Abstract

ISO Prolog provides catch and throw to realise the control flow of exception handling. This pearl demonstrates that catch and throw are inconspicuously amenable to the implementation of backjumping. In fact, they have precisely the semantics required: rewinding the search to a specific point, and carrying of a preserved term to that point. The utility of these properties is demonstrated through an implementation of graph colouring with backjumping and a backjumping SAT solver that applies Conflict Driven Clause Learning.