Programming with Narrowing

Narrowing is a powerful feature found in some declarative programming languages. Research in the last decade has produced significant results on the theory and foundation of narrowing, but little is published on the use of narrowing in programming. This paper introduces narrowing from a programmer viewpoint; outlines the programming language Curry, which provides narrowing as a first class feature; shows, by means of examples, when and how to use narrowing in Curry programs, and discusses the impact of narrowing on software development activities such as design and maintenance