Logic enhancement

Languages based on first order logic have rapidly gained popularity as practical programming languages in several fields. With experience, several problems with the most popular such language, Prolog, have come to light. Several proposals for changes and extensions to Prolog have been made, but proposals have been expensive to build and evaluate. An inexpensive method for extension is described that relies on preprocessors and checkers written in Prolog itself. The method is efficient and applies to any logic programming language that permits manipulation of programs as objects. Several extensions have been built, including modules, macros, functional notation, repetition notation, debugging, and profiling; the first three are explored in detail.