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

Basic sequence transformations


Let's revisit the functional solution of the sample problem from Chapter 1, Begin Thinking Functionally. It represents the common functional pattern of finding a given property of the collection as follows:

  • From the given string literal representing 1000 consecutive single digit characters, make a collection of the collections represented by chunks of just five consecutive single digit characters of the original collection. Each chunk takes the inner characters of a five character-wide stencil aligned first with the left-hand side border of the string literal. The stencil then gets moved to the right by a single character before extracting the next sub collection. This sliding of the stencil to the right is continued until the right-hand side borders of both the stencil and the literal get aligned. To be exact, the main sequence consists of 996 such five character sub sequences.

  • Note that the originally sought-for property of the maximal product of five consecutive...