Book Image

F# 4.0 Design Patterns

By : Gene Belitski
Book Image

F# 4.0 Design Patterns

By: Gene Belitski

Overview of this book

Following design patterns is a well-known approach to writing better programs that captures and reuses high-level abstractions that are common in many applications. This book will encourage you to develop an idiomatic F# coding skillset by fully embracing the functional-first F# paradigm. It will also help you harness this powerful instrument to write succinct, bug-free, and cross-platform code. F# 4.0 Design Patterns will start off by helping you develop a functional way of thinking. We will show you how beneficial the functional-first paradigm is and how to use it to get the optimum results. The book will help you acquire the practical knowledge of the main functional design patterns, the relationship of which with the traditional Gang of Four set is not straightforward. We will take you through pattern matching, immutable data types, and sequences in F#. We will also uncover advanced functional patterns, look at polymorphic functions, typical data crunching techniques, adjusting code through augmentation, and generalization. Lastly, we will take a look at the advanced techniques to equip you with everything you need to write flawless code.
Table of Contents (20 chapters)
F# 4.0 Design Patterns
Credits
About the Author
Acknowledgements
About the Reviewer
www.PacktPub.com
Preface

Chapter 7.  Advanced Techniques: Functions Revisited

This chapter builds upon the basic F# idioms in functions, pattern matching, and data sequences that we have observed in the previous chapters. Here, I turn to the advanced patterns of data transformations, in other words, the repeated use of functions over data. The goal of this chapter is to familiarize you with the major patterns where combined basic F# idioms work in synergy. This chapter covers the following topics:

  • Advanced recursion patterns, including tail recursion and the mutual recursion of functions and sequences

  • Folding as a universal pattern of aggregation

  • Memoization and lazy evaluation as complementary patterns of the just-in-time principle applied to data

  • The continuation passing pattern extending the core call-return principle of function interaction

  • Advanced pattern matching by generalizing matching with active patterns

These synergies often manifest themselves in clean, concise, and efficient F# code.