How languages affect design patterns

Abstract

Software design patterns are a common tool to solving a common set of problems, and are widely used in object-oriented programming. Likewise, functional programming has its own set of patterns and techniques that solve common problems in the functional programming space. In this study, we have examined eight design patterns from Gang of Four’s seminal work Design patterns: Elements of Reusable Object-Oriented Software, and how they apply to functional programming, which functional programming patterns can be used to implement these design patterns, and how applicable are they to an functional programming language. We implemented these patterns in the object-oriented programming language Java and the functional programming language Haskell. From this study, we found that while some design patterns are applicable to functional programming, some were not, and only a few are reasonably useful in an functional programming context.